Patent Application
20050232074
The present invention relates generally to reactors, and in particular, to single or parallel research reactors suitable for use in a combinatorial (i.e., high-throughput) science research program in which chemical reactions are conducted simultaneously using small volumes of reaction materials to efficiently and economically screen large libraries of chemical materials.
Reactors of this type are disclosed in co-owned International Application No. PCT/US 99/18358, filed Aug. 12, 1999, by Turner et al., entitled Parallel Reactor with Internal Sensing and Method of Using Same, published Feb. 24, 2000 (International Publication No. WO 00/09255), which is incorporated herein by reference for all purposes. This PCT application claims priority from the following co-owned, U.S. applications bearing the same title, all of which are also incorporated by reference for all purposes: U.S. application Ser. No. 09/211,982, filed Dec. 14, 1998, by Turner et al., now U.S. Pat. No. 6,306,658, issued Oct. 23, 2001; U.S. Ser. No. 09/177,170, filed Oct. 22, 1998, by Dales et al., now U.S. Pat. No. 6,548,026, issued Apr. 15, 2003; and U.S. provisional application Ser. No. 60/096,603, filed Aug. 13, 1998, by Dales et al. Reactors of the type to which the present invention relates are also disclosed in co-owned U.S. application Ser. No. 09/548,848, filed Apr. 13, 2000, by Turner et al., entitled Parallel Reactor with Internal Sensing and Method of Using Same, the U.S. national application based on the aforementioned PCT application, now U.S. Pat. No. 6,455,316, issued Sep. 24, 2002; U.S. application Ser. No. 09/239,223, filed Jan. 29, 1999, by Wang et al., entitled Analysis and Control of Parallel Chemical Reactions, now U.S. Pat. No. 6,489,168, issued Dec. 3, 2002; and U.S. application Ser. No. 09/873,176, filed Jun. 1, 2001, by Nielsen et al., entitled Parallel Semicontinuous or Continuous Stirred Reactors, which claims the benefit of U.S. provisional applications Ser. No. 60/209,142, filed Jun. 3, 2000, and Ser. No. 60/255,716, filed Dec. 14, 2000, by Nielsen et al. bearing the same title. Reactors of the type to which the present invention relates are also disclosed in co-owned U.S. application Ser. No. 10/116,861, filed Apr. 5, 2002, by Wheeler et al., entitled Combinatorial Chemistry Reactor System, which claims the benefit of U.S. application Ser. No. 09/826,606, filed Apr. 5, 2001, by Chandler, entitled Parallel Reactor for Sampling and Conducting In Situ Flow-through Reactions and a Method of Using Same, now U.S. Pat. No. 6,692,708, issued Feb. 17, 2004; and U.S. application Ser. No. 10/116,862, filed Apr. 5, 2002, by Wheeler, et al., entitled Combinatorial Chemistry Reactor System. Reactors of the type to which the present invention relates are also disclosed in co-owned U.S. application Ser. No. 10/040,988, filed Jan. 7, 2002, by Dales, et al., entitled Apparatus and Methods for Parallel Processing of Multiple Reaction Mixtures, which claims the benefit of U.S. application Ser. No. 09/772,101, filed Jan. 26, 2001, by Dales, et al., bearing the same title, now U.S. Pat. No. 6,759,014, issued Jul. 6, 2004. Reactors of the type to which the present invention relates are also disclosed in co-owned U.S. application Ser. No. 10/060,075, filed Jan. 28, 2002, by Smith et al., entitled Apparatus and Methods for Parallel Processing of Multiple Reaction Mixtures, which claims the benefit of U.S. provisional application Ser. No. 60/264,489, filed Jan. 26, 2001, by Troth et al. bearing the same title, all of which are hereby incorporated by reference for all purposes. These applications disclose a number of embodiments for parallel research reactors suitable for use, for example, in combinatorial chemistry applications, such as polymer research and catalyst research.
Many prior art processing systems use magnetically coupled stirring, but such systems typically are not capable of processing at elevated temperatures, such as those up to 350° C. (660° F.). Typically, magnetic stirring elements enclose magnets within a non-metallic coating, such as plastic, to isolate the magnets from the reaction materials. Such stirring elements are not capable of performing in high temperature reactions because the non-metallic coating is not capable of maintaining its structural integrity at elevated temperatures. Moreover, such prior art systems include magnetic stirrers loosely placed within the bottom of each reaction vessel. Such stirrers are capable of basic mixing of a reaction mixture, but are not capable of stirring highly viscous reaction mixtures, or those reaction mixtures requiring a specific type of stirrer, such as a high shear stirrer. Moreover, such stirrers are generally confined to the lower portion of the reaction vessel, which may limit their ability to stir the entire reaction mixture.
Another type of prior art magnetically-coupled stirring system uses shaft driven stirring, wherein a magnetic feed-through device couples a drive shaft with a stir shaft. Such devices suffer from various drawbacks, including increased headspace above the reaction mixture and increased wettable surface area within the reaction chamber. Such designs provide effective stirring because they are shaft driven, but the increased wettable surface area increases the likelihood of condensation within the reaction chamber, which removes materials from the reaction mixture, thereby potentially altering its chemical composition, which may alter the results of the experiment.
Other processing systems include direct drive stirring systems, wherein a drive shaft passes through an opening in the reactor for shaft stirring the reaction mixture. Such systems require an additional seal, more particularly a dynamic seal, for engaging the shaft and the opening for maintaining the reaction vessel in a sealed condition while the shaft rotates. Dynamic seals are more difficult to maintain and are less capable of performing at elevated temperatures. Moreover, these systems require an additional seal for each reactor, thereby increasing the likelihood of leaks and pressure losses due to improper sealing.
There is a need, therefore, for an improved reactor stirring system that overcomes one or more of the problems articulated above and that is well-suited for reaction temperatures up to 350° C. (660° F.), and/or which reduces the internal volume of the reactor and the amount of wettable surface within the reaction chamber, and/or which eliminates mechanical connections within the reaction chamber and seals between the moving stirrer and the stationary vessel and cap, and/or which provides for increased coupling torque between each stirrer and driver for efficiently stirring more viscous reaction mixtures. Previous reactor systems lack these capabilities.
The present invention also generally relates to systems for effecting the transfer of fluid materials, particularly reaction materials in the form of liquids and gases, to and from one or more reaction vessels of a reactor system. Such fluid transfer systems may include a probe or cannula for holding fluid material, a robot system for transporting the cannula between fluid transfer locations, including a number of reactor vessels, and hard plumbed gas conduits for transferring gaseous components to and from the vessels.
One aspect of the present invention is directed to an apparatus for processing of a reaction mixture comprising a vessel for holding a reaction mixture for processing. A vessel support is adapted for supporting the vessel, and a cap sealingly engages the vessel support for sealing the vessel within the vessel support. The vessel, vessel support, and cap define a reaction chamber. The apparatus further comprises a bearing within the reaction chamber and a stirrer rotatable in the reaction chamber. The stirrer comprises a spindle rotatable in the bearing and at least one stirring implement extending from the spindle for contacting the reaction mixture. The stirrer further comprises at least one magnet on the stirrer adapted to be subjected to a rotating magnetic field in the vessel for causing the stirrer to rotate thereby to mix the reaction mixture.
Yet another aspect of the present invention is directed to an apparatus for parallel processing of reaction mixtures comprising a plurality of vessels for holding a plurality of reaction mixtures for processing. The apparatus further comprises a plurality of vessel supports adapted for supporting one of the plurality of vessels and caps sealingly engaging the vessel supports for sealing the vessels within the vessel supports. The vessels, vessel supports, and caps define reaction chambers having bearings within the reaction chambers and stirrers rotatable in the reaction chambers. Each of the stirrers comprises a spindle rotatable in a respective bearing and at least one stirring implement extending from the spindle for contacting a respective reaction mixture. Each of the stirrers further comprises at least one magnet on the stirrer adapted to be subjected to a rotating magnetic field in the vessel for causing the stirrer to rotate thereby to mix the respective reaction mixture.
Still another aspect of the present invention involves an apparatus for processing of a reaction mixture. The apparatus comprises a vessel adapted for holding the reaction mixture for processing and a stirring system for stirring the reaction mixture in the vessel. The stirring system comprises a stirrer contained in the vessel and a drive mechanism comprising a magnetic driver coupled to the stirrer for rotating the stirrer within the vessel. The stirrer comprises a spindle and a stirring implement on the spindle adapted to contact the reaction mixture in the vessel for stirring the reaction mixture. The stirrer further comprises a first magnetic follower, a second magnetic follower, and a flux guide for guiding magnetic flux between the first magnetic follower and the second magnetic follower. The followers and flux guide of the stirrer create a magnetic flux path between the stirrer and the magnetic driver.
Another aspect of the present invention is directed to an apparatus for parallel processing of reaction mixtures comprising a plurality of vessels sealed against fluid communication with one another and adapted for holding reaction mixtures for processing. A stirring system for stirring the reaction mixtures in the vessels comprises a plurality of stirrers contained in the vessels and a drive mechanism comprising a plurality of magnetic drivers coupled to the stirrers for rotating the stirrers within the vessels. Each stirrer comprises a spindle and a stirring implement on the spindle adapted to contact the reaction mixture in the vessel for stirring the reaction mixture. Each stirrer further comprises a first magnetic follower, a second magnetic follower, and a flux guide for guiding magnetic flux between the first magnetic follower and the second magnetic follower. The followers and flux guide of each stirrer of the plurality of stirrers create a magnetic flux path between the stirrer and a respective one of the plurality of magnetic drivers.
Yet another aspect of the present invention involves a stirring system for use in a reactor. The system comprises a vessel for holding a reaction mixture for processing. A stirrer is received in the vessel. The stirrer comprises a spindle including an upper end, a lower end, and at least two stirring elements adjacent the lower end. A first magnetic follower is sealed inside one of the at least two stirring elements, and a second magnetic follower is sealed inside another of the at least two stirring elements. The magnetic pole axis of the first magnetic follower and the magnetic pole axis of the second magnetic follower are not parallel. A drive mechanism for generating a rotating magnetic field in the vessel rotates the stirrer and thereby mixes the reaction mixture.
In still another aspect, a stirring system for use in a parallel reactor comprises a plurality of vessels for holding a plurality of reaction mixtures for processing. Stirrers are received in the vessels, each of the stirrers comprising a spindle including an upper end, a lower end and at least two stirring elements adjacent the lower end. A first magnetic follower is sealed inside one of the at least two stirring elements and a second magnetic follower is sealed inside another of the at least two stirring elements. The magnetic pole axis of the first magnetic follower and the magnetic pole axis of the second magnetic follower are not parallel. A drive mechanism for generating a rotating magnetic field in each of the plurality of vessels rotates the stirrers and thereby mixes the reaction mixtures.
In another aspect, a stirrer for use in a reactor comprises a spindle adapted to be mounted in a vessel for rotation on a longitudinal axis of the spindle. A stirring implement on the spindle is rotatable therewith for contacting a reaction mixture in the vessel. First and second magnetic followers comprise at least two spaced-apart permanent magnets rotatable with the spindle and the at least one stirring implement. A flux guide between the spaced-apart permanent magnets and rotatable therewith guides magnetic flux between the at least two spaced-apart permanent magnets. The at least two spaced-apart permanent magnets are arranged such that when they are subjected to a rotating magnetic field, the stirrer is adapted to rotate in the vessel to mix the reaction mixture.
In still another aspect, a stirrer for use in a reactor comprises a spindle adapted to be mounted in a vessel for rotation on a longitudinal axis of the spindle, a helical blade on the spindle, and at least two stirring elements projecting from the spindle. At least two magnets sealed inside the stirring elements are positioned and configured such that subjecting the magnets to a rotating magnetic field induces rotation of the stirrer.
In another aspect, an apparatus for processing of reaction mixtures comprises a base, a vessel support mounted on the base, a vessel supported by the vessel support, a cap, and a head for holding the cap. The cap is movable with the head between a first position in which the cap sealingly engages the vessel support to seal the vessel in the vessel support, and a second position in which the cap is clear of the vessel support to provide access to the vessel.
In yet another aspect, an apparatus for parallel processing of reaction mixtures comprises a base, a plurality of vessel supports mounted on the base, a plurality of vessels supported by the vessel supports, a plurality of caps, and a head for holding the caps. The caps are movable with the head between a first position in which the caps sealingly engage the vessel supports to seal the vessels in the vessel supports, and a second position in which the caps are clear of the vessel supports to provide access to the vessels.
In another aspect, an apparatus for processing of a reaction mixture comprises a reactor module comprising a reactor for containing a reaction mixture, a vessel platform for mounting the reactor, and a head movable with respect to the vessel platform. The head carries a cap corresponding to the reactor, the head being movable between a raised position and a lowered position in which the cap carried by the head sealingly engages the reactor. The apparatus further comprises an enclosure for enclosing the reactor module, the enclosure comprising a framework supporting the reactor module and walls enclosing the framework and reactor module.
In still another aspect, an apparatus for parallel processing of reaction mixtures comprises a reactor module comprising a plurality of reactors for containing the reaction mixtures, a vessel platform for mounting the plurality of reactors, and a head movable with respect to the vessel platform. The head carries a plurality of caps corresponding to the reactors and is movable between a raised position and a lowered position in which the caps carried by the head sealingly engage the reactors. An enclosure encloses the reactor module and comprises a framework supporting the reactor module and walls enclosing the framework and reactor module.
In a further aspect, a method of making and characterizing materials comprises the steps of providing vessel supports with starting materials to form reaction mixtures, confining the reaction mixture in each vessel support against fluid communication with the other vessel supports and at a pressure other than ambient pressure, stirring the reaction mixtures for at least a portion of the confining step, and controlling the temperature of the headspace within the vessel supports above the reaction mixture for at least a portion of the confining step.
In yet another aspect, apparatus for processing of a reaction mixture comprises a vessel adapted for holding a reaction mixture for processing and a stirring system for stirring the reaction mixture in the vessel. The stirring system comprises a stirrer contained in the vessel, and a drive mechanism comprising a magnetic driver coupled to the stirrer for rotating the stirrer within the vessel. The stirrer comprises a spindle and a stirring implement on the spindle adapted to contact the reaction mixture in the vessel for stirring the reaction mixture. The stirrer further comprises a first magnetic follower, a second magnetic follower, and a flux guide for guiding magnetic flux between the first magnetic follower and the second magnetic follower. The followers and flux guide of the stirrer create a magnetic flux path between the stirrer and the magnetic driver.
In still another aspect, a stirring system for use in a reactor comprises a vessel for holding a reaction mixture for processing, a stirrer received in the vessel. The stirrer comprises a spindle including an upper end, a lower end, and at least two stirring elements adjacent the lower end. A first magnetic follower is sealed inside one of the at least two stirring elements and a second magnetic follower is sealed inside another of the at least two stirring elements. The magnetic pole axis of the first magnetic follower and the magnetic pole axis of the second magnetic follower are not parallel, and a drive mechanism generates a rotating magnetic field in the vessel to rotate the stirrer and thereby mix the reaction mixture.
In another aspect, apparatus for processing of a reaction mixture comprises a vessel for holding a reaction mixture for processing, a vessel support adapted for supporting the vessel, and a cap sealingly engaging the vessel support for sealing the vessel within the vessel support. The vessel, vessel support, and cap define a reaction chamber having a bearing within the reaction chamber and a stirrer rotatable in the reaction chamber. The stirrer comprises a spindle rotatable in the bearing and at least one stirring implement extending from the spindle for contacting the reaction mixture. The stirrer further comprises at least one magnet on the stirrer adapted to be subjected to a rotating magnetic field in the vessel for causing the stirrer to rotate thereby to mix the reaction mixture.
In yet another aspect, a stirring system for use in a reactor comprises at least one vessel for holding a reaction mixture for processing. The at least one vessel has a convex bottom surface. A stirrer in the at least one vessel comprises at least one stirring element and a magnetic follower sealed inside the stirring element. A drive mechanism generates a rotating magnetic field in the at least one vessel to rotate the stirrer and thereby mix the reaction mixture. The drive mechanism comprises a rotatable magnetic driver associated with the at least one vessel to generate the rotating magnetic field in the vessel. The rotatable magnetic driver comprises a first concave surface facing the convex bottom surface of the at least one vessel. The surfaces have substantially the same shape to maintain a substantially uniform spacing therebetween.
In still another aspect, apparatus for processing of a reaction mixture comprises a vessel adapted for holding a reaction mixture for processing and a stirring system for stirring the reaction mixture in the vessel. The stirring system comprises a stirrer contained in the vessel, and a drive mechanism comprising a magnetic driver coupled to the stirrer for rotating the stirrer within the vessel. The stirrer comprises a first magnetic follower, a second magnetic follower, and a flux guide for guiding magnetic flux between the first magnetic follower and the second magnetic follower.
A stirring system for use in a reactor comprises at least one vessel for holding a reaction mixture for processing and a stirrer in the at least one vessel. The stirrer comprises first and second magnetic followers and a flux guide for guiding magnetic flux between the first magnetic follower and the second magnetic follower. A drive mechanism generates a rotating magnetic field in the at least one vessel to rotate the stirrer and thereby mix the reaction mixture.
Other objects and features will be in part apparent and in part pointed out hereinafter.
Corresponding parts are designated by corresponding references numbers throughout the drawings.
Reactor Module Overview
Referring now to the drawings and specifically
As depicted generally in
Two stops 77 on the vessel platform 47 limit downward movement of the head 51 so that it remains spaced above the vessel platform in its lowered position. A microswitch 79 mounted on an upper end of one of these stops 77 provides a signal to the apparatus 41 to allow for heating of the vessels (discussed below), such that if the head is not in its lowered position or is moved from its lowered position during use of the reactor, no reactor heating can occur. In the embodiment shown and described, the head 51 moves with respect to the stationary vessel platform 47. However, it is contemplated that the head 51 may remain stationary while the vessel platform 47 moves up and down, without departing from the scope of the present invention. In another embodiment, the microswitch 79 may mount beneath the vessel platform 47 in a position where one of the vertical guide rods 55 engages the microswitch when the head 51 moves to its lowered position.
The head 51 carries, among other things, an N number of caps 85 corresponding to the N number of reactors 49, for sealing the reactors. As depicted in
Reactor Configuration
The vessel 105 may be made of glass or other suitably chemically inert material capable of withstanding high-temperature chemical reactions. As shown in
In the embodiment shown, the vessels 105 have a total volume of between about 10 milliliters (ml) (0.34 ounce (oz)) and about 80 ml (2.7 oz). More specifically, the vessels 105 have a total volume of between about 10 ml (0.34 oz) and about 50 ml (1.7 oz). More particularly, the vessels 105 have a total volume of between about 12 ml (0.41 oz) and about 40 ml (1.4 oz). The working volume of a particular vessel 105 is defined as the volume of the vessel 105 occupied by the reaction materials. In the embodiment shown, the vessels 105 have a working volume of between about 10 ml (0.34 oz) and about 50 ml (1.7 oz). More specifically, the vessels 105 have a working volume of between about 10 ml (0.34 oz) and about 40 ml (1.4 oz). More particularly, the vessels 105 have a working volume of between about 12 ml (0.41 oz) and about 30 ml (1.0 oz). Vessels 105 having other total volumes and other working volumes are also contemplated as within the scope of the present invention. In addition to these volumes, the vessels 105 of the depicted embodiment have particular aspect ratios that enhance the mixing of the reaction mixtures. In general, for thorough mixing much of the reaction mixture should be near the rotating stirrer, so that a large percentage of the reaction mixture is agitated during stirring. Moreover, a reaction mixture held in a substantially cylindrical vessel 105 having a mixture depth d similar in dimension to the vessel diameter D will facilitate thorough mixing by maintaining much of the reaction mixture in a substantially globular volume, wherein the maximum dimension of the reaction mixture in any direction is not substantially different than the minimum dimension of the reaction mixture in any direction. In other words, for effective mixing it is preferable that none of the reaction mixture be substantially isolated from either the rotating stirrer or other portions of the reaction mixture. By way of example, the depicted vessels 105 have an aspect ratio (length over diameter (L/D)) of less than about 4. More specifically, the vessels have an aspect ratio (L/D) of less than about 3. Even more particularly, the vessels have an aspect ratio (L/D) of less than about 2.
Each reactor module 43 further comprises a stirring system, generally indicated 131 (
Low Shear Stirrers
Referring now to
The stirrer 153 further comprises spaced apart magnets 175 mounted on the stirrer (
In addition to the first and second magnetic followers 179,185, the stirrer 153 may contain a flux guide, generally indicated 197, for guiding magnetic flux F between the first magnetic follower and the second magnetic follower. In one embodiment, the flux guide 197 comprises one or more guide elements 199 in a passage 201 in the stirrer 153 extending between the cavities 181,187 containing the magnets 175. Each of the one or more guide elements 199 need not be a permanent magnet, but may be constructed of ferromagnetic material to encourage magnetic flux F passage between the first and second magnetic followers 179,185. In one example, each guide element 199 may be constructed of steel, in particular 1018 steel having adequate ferromagnetic properties. In contrast, the stirrer 153 itself, including the spindle 155, stirring elements 165, and plugs 191, are constructed of a material with a lower magnetic flux permeability than the guide element(s) 199. This encourages magnetic flux F to travel through the permanent magnets 175 and flux guide 197 rather than through the stirrer body itself. In one example, the stirrer 153 may be constructed of stainless steel, which is a relatively low flux permeability. The use of a flux guide 197 channels flux F in a proper magnetic flux path, rather than allowing flux to travel throughout the stirrer 153. Is should be noted here that in another example, the flux guide 197 may be omitted from the stirrer 153 without departing from the scope of the present invention.
In the configuration shown, the magnetic pole axis A of the first magnetic follower 179 and the magnetic pole axis B of the second magnetic follower 185 are not parallel. In particular, an included angle it between the magnetic pole axis A of the first magnetic follower 179 and the magnetic pole axis B of the second magnetic follower 185 is one of less than and equal to about 3.1 radians (180 degrees). More particularly, the included angle α between the magnetic pole axis A of the first magnetic follower 179 and the magnetic pole axis B of the second magnetic follower 185 is one of less than and equal to about 2.6 radians (150 degrees). More particularly, the included angle α between the magnetic pole axis A of the first magnetic follower 179 and the magnetic pole axis B of the second magnetic follower 185 is one of less than and equal to about 2.1 radians (120 degrees). By orienting the magnetic pole axes A,B laterally or toward the magnetic driver 145 (downward in
Referring again to the geometry of the stirrer 153 of
In addition to the stirring elements 165, the stirring implement 161 further comprises at least one paddle, generally indicated 213, extending from the spindle 155 adjacent its lower end 167. In the illustrated embodiment, the paddle 213 extends substantially perpendicular to the vertical plane containing the stirring elements 165 and includes two substantially planar blades 215 projecting laterally from opposite sides of the spindle 155 in planes that are skewed relative the longitudinal axis S of the spindle. These blades 215 ensure that the reaction materials near the bottom of the vessel 105 are adequately agitated during stirring.
As will be discussed in greater detail below, the magnetic drivers 145 beneath the vessels 105 are operable to generate rotating magnetic flux fields F in the vessels. In combination with these rotating magnetic fields F, the followers 179,185 and flux guide 197 of each stirrer 153 create a magnetic flux path (
In addition to responding to the rotating magnetic drivers 145, the stirrers 153 are also preferably capable of operation at elevated temperatures. In one example, the stirrers 153 may be capable of operation at temperatures from about 0° C. (30° F.) to about 350° C. (662° F.). More specifically, the stirrers 153 may be capable of operation at temperatures from about 20° C. (68° F.) to about 200° C. (390° F.). More particularly, the stirrers 153 may be capable of operation at temperatures from about 40° C. (100° F.) to about 160° C. (320° F.). Operating at such temperatures requires a stirrer 153 formed of a material stable at high and low temperatures, such as stainless steel.
In another example, the stirrer 153 may be formed from other materials, such as a chemically-resistant plastic, like polyethylethylketone (PEEK), polytetrafluoroethylene (PTFE), and the like. Such stirrers 153 may be capable of operation at temperatures from about 0° C. (300° F.) to about 200° C. (390° F.). More specifically, the stirrers 153 may be capable of operation at temperatures from about 20° C. (68° F.) to about 170° C. (340° F.). More particularly, the stirrers 153 may be capable of operation at temperatures from about 40° C. (100° F.) to about 150° C. (300° F.). In still another example, the stirrer 153 and/or the magnetic followers 179,185 may be Teflon-encapsulated for isolation from the reaction mixture.
In addition to the temperature considerations associated with the integrity of the stirrer material at elevated reaction temperatures, the magnetic performance of the permanent magnets within the stirrer may also be considered during magnet selection.
Instead of the stirrer 153 described above, the vessels 105 may also receive conventional magnetic stir bars (not shown) for driving rotation by the rotating magnetic fields F described above. Such stir bars may include a single permanent magnet, or first and second magnetic followers, generally as set forth above. The single permanent magnet or magnetic followers may be Teflon-encapsulated for isolation from the reaction mixture.
Vessel/Bearing/Stirrer Assembly
Turning to
Each assembly 221 comprises a bearing 137 having a hub 225 including an opening 227 for rotatably receiving a portion (upper end 157) of the rotatable spindle 155 of a respective stirrer 133. The upper end 157 of the rotatable spindle 155 freely rotates within the opening 227 in the bearing 137, thereby orienting the stirrer 133 and bearing with respect to one another. The bearing 137 additionally comprises two arms 231 extending radially outward from the hub 225 for engagement with the vessel 105 to support the bearing within the vessel 105. To accommodate these arms 231, the vessel 105 includes two recesses 235 for receiving corresponding registration members 237 located at the outer ends of the arms of each bearing 137. These registration members 237 locate the bearing 137 within the vessel 105 in a generally circumferential direction. In addition, the bearing 137 includes support members 241 extending from the arms 231 for engaging an upper rim 243 of the vessel 105 for locating the bearing in a generally axial (vertical as shown) direction with respect to the vessel. Thus, the arms 231, registration members 237, and support members 241 cooperate to secure and orient the bearing 137 and stirrer 133 within the vessel 105. In one embodiment, the arms 231 are resilient and have curved end portions, generally indicated 247 in
Referring now to
High Shear Stirrer
Still another stirrer of the present invention, generally indicated 453, is depicted in
The high shear stirrer 453 of
The mixing arms 483 of the stirrer 453 are configured to develop high shear forces during stirring. In the illustrated embodiment, each arm 483 has a convex top face 503 curving down from the central hub 477 of the stirrer 453, a convex bottom face 507 curving down from the outer end of the top face to the central hub of the stirrer, and a pair of flat, opposing side surfaces 511 lying in generally parallel planes extending generally axially of the stirrer. (In other words, the side surfaces 511 are oriented substantially perpendicular to a circular path traced by the mixing arm 483 as the stirrer 453 rotates.) The top face 503, bottom face 507, and side faces 511 intersect along relatively sharp, angular, abrupt edges 517 that, during stirring, slice through the reaction mixture, thereby creating high shear forces within the reaction mixture. Further, the relatively broad, flat side faces 511 of the mixing arms 483 contact a substantial volume of material as they sweep through a rotation to effect substantial mixing of the reaction mixture. Such a high shear stirrer 453 may be useful in dispersing components within the reaction mixture, such as with micro-emulsions. The stirrer 453 further comprises a paddle, generally indicated 521, mounted on the spindle 455 at a location above the stirring implement 461. The paddle 521 includes a central sleeve 523 surrounding the spindle 455, and a pair of blades 525 projecting radially outward from the sleeve 523 in opposite directions. The blades 525 have broad, substantially planar side faces 527 oriented substantially perpendicular to the circular path followed by the paddle 521 as it rotates. The upper, lower, and outer edges 529 of the blades 525 are also sharp (angular, abrupt) for creating high shear forces within the reaction mixture during rotation.
The stirrer 453 may be constructed of chemically-resistant plastic material, such as a perfluoro-elastomer, a polyethylethylketone, or a polytetrafluoroethylene, for example. The stirrer 453 may also be constructed of a material stable at high temperatures, such as stainless steel.
Uniform Low Shear Stirrer
Yet another stirrer of the present invention, generally indicated 553, is depicted in
The stirrer 553 further comprises spaced apart magnets 575 mounted on the stirrer. The magnets 575 provide the coupling between the stirrer 553 and the drive mechanism 141, thereby inducing rotation of the stirrer via a rotating magnetic field F. In particular, the magnets 575 are sealed inside the base 573 of the stirring implement 561 to protect them from the reaction mixture. The magnets 575 are adapted to be subjected to a rotating magnetic field F in the vessel 105 for causing the stirrer 553 to rotate and thereby to mix the respective reaction mixture. In the illustrated embodiment, the magnets 575 comprise a first magnetic follower 579 received inside a first cavity 581 of the stirring implement 561 and a second magnetic follower 585 received inside a second cavity 587 of the stirring implement substantially as set forth above. Although not shown, another example of the stirrer 553 may additionally contain a flux guide for guiding magnetic flux between the first magnetic follower 579 and the second magnetic follower 585. In yet another example, the spaced apart magnets 575 may comprise a single permanent magnet.
Drive Mechanism
In general, each magnetic driver 145 of the drive mechanism 141 for rotating the stirrers 133 comprises a driver framework 661, at least one magnetic driver element 663 in the driver framework, and at least one flux guide 667 in the driver framework for guiding magnetic flux F between the magnetic driver element and the stirrer. In one embodiment (
The poles of the first and second magnetic driver elements 663A,663B are oriented substantially opposite with respect to one another, as depicted in
A first flux guide 667A is received in one cavity 679 of the framework 661 above the first magnetic driver element 663A for guiding flux F toward the first magnetic follower 179 of the stirrer 153, and a second flux guide 667B is similarly situated in the other framework cavity atop the second magnetic driver element 663B for guiding flux toward the second magnetic follower 185 of the stirrer. The first and second flux guides 667A,667B include first and second concave surfaces 687,689, respectively, shaped and sized to face the vessel 105 and vessel support 99. In addition, the upper surface 671 of the driver framework 661 is also concave and has about the same radius of curvature as the upper concave surfaces 687,689 of the flux guides 667. The first cavity 679A and the first flux guide 667A are keyed with respect to one another for orienting the first flux guide with respect to the driver framework 661. The second cavity 679B and the second flux guide 667B are similarly keyed with respect to one another. In particular, the sidewall of each cavity 679 of the driver framework 661 includes a pair of opposed channels 693 extending lengthwise of the cavity (vertically as shown in
In the embodiment shown in
Thus, the magnetic driver 145 and stirrer 153 cooperate to create a strong magnetic field, having flux F flowing along a magnetic flux path (
The permanent magnets 683 may be constructed of Samarium Cobalt Grade 28, Grade 18, or Grade 20 magnetic materials. Other rare earth or permanent magnetic materials are also contemplated as within the scope of the present invention. In one example, magnet selection may be influenced by the temperature requirements of the reactor. Moreover, the driver framework 661 is specifically configured to resist transmitting magnetic flux F. In particular, the driver framework 661 is constructed of a material having a low magnetic flux permeability, such as aluminum.
Each magnetic driver 145 further comprises a drive shaft 705 connected to the driver base 675 for rotating the driver base and driver framework 661 (
It will be understood that the magnetic drivers 145 may be rotated by other types of drive mechanisms 141, such as chain drives, gear drives, etc. Also, each magnetic driver 145 may be rotated by an independent drive system (e.g., individual reactor motors) so that the rotational speed of the corresponding stirrer 133 can be varied independent of the speed of the other stirrers.
Vessel Sealing
Turning to
As best shown in
Each cap 85 is releasably held in assembly with the head 51 by the cap retainer, one version of which is indicated at 93 in
Each cap 85 is provided with a suitable number of fastener holes 801 for receiving fasteners (not shown) which thread into the vessel support 99 to secure the cap 85 in place during a reaction process. The upper ends of these holes 801 are recessed below the top surface 741 of the cap 85 so the fastener heads do not project above the caps. (It is also contemplated that the upper ends of the holes may not be recessed below the top surface of the cap.) When the fasteners are tightened, the annular bottom surface 745 of the cap 85 compresses a seal 803 (e.g., an O-ring seal) received in a groove 805 in the top surface 757 of the vessel support 99 to seal the respective reaction chamber 123. Alternately, the seal 803 may be on the underside of the cap 85. The vessel supports 99, vessels 105, and caps 85 are constructed for conducting reactions at pressures different from ambient pressure. In particular, the vessel supports 99, vessels 105, and caps 85 are constructed for conducting reactions at gage pressures from about zero kilopascals (kPa) (zero pounds per square inch (psi)) to about 3400 kPa (500 psi), more specifically, from about 340 kPa (50 psi) to about 2800 kPa (400 psi), even more particularly from about 690 kPa (100 psi) to about 2400 kPa (350 psi), and still more specifically from about 1400 kPa (200 psi) to about 2100 kPa (300 psi).
When the fasteners are removed from the vessel support 99 and fastener holes 801, the retainers 93 hold the caps 85 in position on the head 51. This ensures that any instruments extending down from the cap 85 into the vessel 105, such as the probes discussed below, do not contact the stirrer 133, for example, when the head 51 moves to its raised position. Without the retainers 93 in position, the caps 85 may tilt slightly with respect to the head 51, thereby allowing contact between the instruments and stirrer 133, which should be avoided.
Temperature Control
Another feature of this invention is a temperature control system operable to maintain the vessels 105 at selected temperatures independent of one another, so that reaction mixtures in different vessels may simultaneously be maintained at different precise temperatures during parallel processing. For controlling temperature, each reactor 49 includes a number of temperature control features designed to uniformly control temperatures throughout the reactor. One such feature comprises a temperature control jacket 811 surrounding each vessel support 99 and secured with fasteners 813 for independently controlling the temperature of the reaction mixture in the vessel 105. The control jacket 811 is depicted in
A second temperature control feature comprises at least one additional heater 815 for controlling the temperature of the cap 85 and the headspace above the reaction mixture. Controlling the temperature of the headspace is desirable because it discourages the formation of condensation within the reaction chamber 123. Condensation is undesirable because of its tendency to hold reaction constituents away from the reaction mixture, thereby potentially altering the makeup of the reaction mixture. Heating the headspace above the reaction mixture reduces condensation within the reaction chamber 123 by maintaining the portion of the reaction chamber above !he reaction mixture and the cap 85 at a higher temperature, such that gaseous components are less inclined to collect on the cap and vessel 105 wall portions exposed in the reaction chamber. As best depicted in
Two temperature probes 831 are associated with each of the reactors 49 for controlling the heat output of the jacket 811 and the cap heater 815 associated with the reactor. One of two temperature probes 831C attaches to the outside of the vessel support 99 and is operable to sense the temperature of the vessel support (
It should be noted that more, or fewer, temperature probes 831 may be included without departing from the scope of this invention. In one example, an over-temperature probe 831A (
Monitoring Other Parameters
In addition to monitoring temperature, other parameters of the reaction mixture may also be monitored by passing probes through other passages 841 in the cap 85 to positions in communication with the reaction chamber 123 of each reactor vessel 105 (
Fluid Transfer System
The apparatus 41 further comprises a fluid transfer system for transferring fluids to and from the several vessels 105 while the vessels are at pressures other than ambient pressure. In one embodiment (
The vent conduits 853 connect to a vent gas manifold 881, which includes a plurality of inlet gas valves 883 for selective opening and closing to allow pressurized gas to vent from particular vessels 105 (
As will be discussed in greater detail below, the parallel processing apparatus 41 may comprise a number of reactor modules 43 mounted side-by-side on a frame 911 for operation together, each module comprising a plurality of reactors (e.g., eight reactors). Six such reactor modules 43 are shown in
In one example, the operation of the sensors 891 and the valves 883,895 may be under the control of a suitable controller, such as a computer, comprising software or hardware for receiving pressure information from at least one of the sensors for controlling the operation of the associated valves, which ultimately control the pressure within the associated reactor.
In addition to transfer of gaseous components, the fluid transfer system preferably comprises structure for introduction and withdrawal of fluids to and from the vessels 105 via fluid transfer probe. As discussed above, each of the caps 85 includes passages 841 for communicating with a respective reaction chamber 123. In the embodiment depicted in
In order to maintain the reactor 49 in a sealed condition during insertion into the passage 841 and after withdrawal of the probe from the passage, a sealing mechanism is disposed in the passage to maintain the reactor in a sealed condition. The sealing mechanism receives the fluid transfer probe and maintains the vessel seal as the fluid transfer probe is inserted and withdrawn from the sealing mechanism, thus preventing any substantial pressure losses if the pressure in the reaction vessel 105 is positive, or any pressure gains if the pressure in the reaction vessel is negative with respect to ambient pressure. In one embodiment, the sealing mechanism comprises a valve and a seal, which may be separate elements or formed as a single unit. The valve is movable between a closed position for closing the passage 841 and an open position permitting movement of the probe through the passage. The seal is disposed in the passage and sealingly engages the probe when the valve is in its open position, thereby maintaining pressure within the reaction chamber 123. In one embodiment, the valve is a duckbill valve. An example of such a sealing mechanism is disclosed in U.S. Pat. No. 4,954,149, incorporated herein by reference, owned by Merlin Instrument Company of Half Moon Bay, Calif.
Each of the probe passages 841 is appropriately located on the cap 85 so that the fluid transfer probe, or any other probe, can pass freely into a respective vessel 105 without interference with the bearing 137 and stirrer 133 in the vessel. In this regard, when the vessel 105, bearing 137, stirrer 133, vessel support 99, cap 85, and head 51 are properly assembled, the various registration elements 771,773 described above hold the components in an orientation relative to one another in which a clearance space or volume 935 is maintained with respect to each passage 841 to permit unrestricted passage of the probe through the passage and into the reaction chamber 123. This clearance volume 935 is shown in
It should be noted that the gas conduits 851,853 and fluid transfer probe may be utilized simultaneously in the same reactor 49. The operation of the robot system, the various valves 867,883 for delivering gases to and from the reactor vessels 105, and other electronic components of the system are under the control of a suitable system processor and software (or firmware), such as a computer, as described below with respect to
Opening the Reactors
Extracting One or More Caps
In some situations, it is beneficial to terminate the reaction within a particular reactor or reactors 49 of a reactor module 43, while allowing the reactions in the remaining reactors to continue. In one example, if one reaction is complete, but others are to be continued for some time, it may be efficient and cost-effective to remove the used contents of the completed reaction and restart a new reaction in the same reactor 49.
In particular, the reactor cap extractor 961 comprises an upstanding framework 965 that may be mounted on the head 51 adjacent a particular reactor 49 for extraction of the cap 85. The framework 965 includes a rod 969 positioned over the center of the cap 85 and slidable in a vertical direction with respect to the reactor 49. The rod 969 has a threaded lower end 971 that threads into an opening 975 on the cap 85 (
Once the framework 965 is mounted on the head 51, the reactor cap extractor 961 is ready for use. The threaded lower end 971 of the rod 969 is screwed into the threaded opening 975 of the cap 85 to connect the cap to the rod of the extractor 961. The retainer 93 may then be released by pushing the retaining member 781 downward against the bias of the spring(s) 795 and rotating the retainer to remove the locking elements 783 from their respective slots 785. The retainer 93 can then be lifted off of the cap 85 and out of the cap opening 753 in the head 51. The fasteners securing the cap 85 to the vessel support 99 are then removed, so that the cap may be lifted from its corresponding vessel support. A ball 983 mounted on an upper end of the rod 969 is then pulled upward, thereby raising the rod and lifting the cap 85 from the vessel support 99. Because the framework 965 maintains the rod 969 in a vertical position, the probes 831 extending down from the cap 85 move upward along a linear vertical path, thereby maintaining an appropriate clearance with respect to the rotating stirrer 133. As the cap 85 is raised, the locking tab 771 of the cap 85 aligned with the vertical channel 979 in the framework 965 of the extractor 961 slides freely up through the channel until it passes a spring-biased catch 987, which holds the cap in a fully raised position until released by the user. Thus, the extractor 961 maintains the orientation of the cap 85 and probe(s) 831 relative to the stirrer 133, thereby eliminating the possibility of interference as the cap is removed. Once the cap 85 is lifted, the used vessel/bearing/stirrer assembly 221 in the reactor 49 may be removed by an assembly removal tool (not shown) using removal holes 991 located toward an upper end of the vessel 105 (
In an effort to reduce spillage during such a reactor changeover, a drip funnel, generally indicated 995, may be seated on the vessel support 99 in place of the cap 85 to collect and direct any liquid material dripping from the caps and/or probe 831 into the well 111 of the vessel support. A mouth 997 of the drip funnel 995 is wider than the cap opening 753 to inhibit drips from falling onto portions of the head 51 adjacent the opening or between the vessel support 99 and the cap opening. To secure the funnel 995 in place, a bottom surface 999 of the funnel includes keyways 1003 which mate with keys 763 in keyways 765 in the top surface 757 of the vessel support 99. As discussed above with respect to the cap 85, the number of keys 763 (or other alignment devices) used may vary. Once the funnel 995 is installed, the used assembly 221 may be removed from the vessel support 99 and any liquid dripping from the assembly or the cap 85 held by the extractor 961 will be caught by the drip funnel and directed toward the open well 111 of the vessel support, rather than falling upon the head 51 of the reactor module 43.
As discussed above with respect to the reactor cap extractor 961, it may be desirable to remove and replace a particular reactor 49,1049 while the other reactors continue under reaction conditions. In this situation, it is important to lower the temperature of the reactor 49,1049 to near ambient before extracting the cap 85 and removing the assembly 221. The cooling fans 1057 associated with each reactor 49,1049 may be selectively activated to cool a particular reactor while the other reactors are maintained at higher temperatures, thereby facilitating the cooling process and leading to a further reduced turn-around time of the individual reactor. Moreover, the cooling assemblies 1047 may be activated together when it is desirable to cool all the reactors 49,1049 of the reactor module 43,1043, such as during a turn-around of the entire reactor module. In one example, the operation of the cooling fans 1057 may be under the control of a suitable controller, such as a computer, comprising software or hardware for receiving temperature, pressure, user input, or other information for controlling the operation of the cooling fans or fan, which ultimately controls the cooling the associated reactors or reactor, respectively.
Operation of the Apparatus
The general operation of the apparatus 41 will now be described. In use, the head 51 is initially raised to allow access to the reactors 49. If reactions have been performed, the used assemblies 221, each comprising a vessel 105, a bearing 137, a stirrer 133, and a reaction mixture, are removed from the vessel supports 99 using a suitable tool and the holes 991 in the wall of the reactor vessel near its upper end (
Once the new assemblies 22i are received in the vessel supports 99, the head 51 is lowered into position over the reactors 49 of the vessel platform 47 by depressurizing the linear actuator 57. The two stops 77 on the vessel platform 47 limit downward movement of the head 51 so that it remains spaced above the vessel platform in its lowered position. The microswitch 79 mounted on an upper end of one of these stops 77 provides a signal to the apparatus 41 to allow for heating of the vessels when the head 51 reaches its lowered position. In this position, the head 51 does not contact the vessel supports 99, thereby thermally isolating the vessel supports from the head.
After the caps 85 are placed on respective vessel supports 99, fasteners are used to secure each cap to a corresponding vessel support. With the fasteners tightened, the annular bottom surface 745 of the cap 85 compresses the seal 803 to seal the respective reaction chamber 123. Once sealed, the reactions may occur generally as set forth above, and as similarly described in the parallel reactor system described in the aforementioned publications and applications, including U.S. application Ser. No. 09/548,848, filed Apr. 13, 2000, now U.S. Pat. No. 6,455,316, issued Sep. 24, 2002.
When the reactions are complete, or after termination of one or more reactions with a quench gas delivered via the supply conduits 851, any non-ambient pressure within the reaction chambers may be relieved via the vent conduits 853 by opening the gas valves 883 of the vent gas manifold 881. Moreover, the drive mechanism 141 and the heating devices 811,815 may be deactivated to stop heating and stirring the reaction mixtures, while the cooling fans 1057 may be activated to collectively cool the reactors 49. With the reactions complete and the reactors 49 cooled and depressurized, the fasteners securing the caps 85 to the vessel supports 99 are removed. The air cylinder 67 is then activated to raise the head 51 to its raised position, after which the used assemblies 221 are removed and replaced with new assemblies containing new reaction mixtures. The head 51 is then lowered to position the caps 85 on the vessel supports 99. After the caps 85 have been fastened to respective vessel supports 99, a new set of reactions may begin.
As noted above in describing the reactors 49 of the present invention, the embodiments described above describe multiple reactors, but it should be understood that the apparatus 41 of the present invention may include only one reactor having a single vessel 105 containing a single reaction mixture.
Multiple Reactor Modules
The parallel processing apparatus 41 comprises a number of reactor modules 43, each having a plurality of reactors 49 (e.g., eight reactors), mounted side-by-side on a framework 1081. A framework capable of supporting six such reactor modules 43 is shown in
In one example, depicted in
The cabinet 1085 additionally houses several other components of the apparatus 41, including the computer 1121 under control of the data input device for controlling the operations of the apparatus, a power distribution unit 1125 for distributing power to the components of the apparatus, over-temperature controllers 1129 connected to the over-temperature probe 831 A for determining when a particular reactor 49 passes the over-temperature threshold, heater controllers 1133 for controlling the operation of the heaters 811,815,and fan control modules 1137 for controlling the operation of the fans 1057. In one example, combining three over-temperature controllers 1129, each having 16 zones, allows for over-temperature control of 48 zones, corresponding to one over-temperature probe 831A per reactor 49 of a 48 reactor apparatus. An exemplary over-temperature controller 1129 is the Watlow 2×8 Zone controller, available from Watlow Electric Manufacturing Company of St. Louis, Mo., U.S.A. In another example, combining three heater controllers 1133, each having 32 zones, allows for control of 96 zones, corresponding to two heaters 811,815 per reactor 49 of a 48 reactor apparatus. An exemplary heater controller 1133 is the Watlow MLS332 controller, available from Watlow Electric Manufacturing Company of St. Louis, Mo., U.S.A. In yet another example, combining three fan control modules 1137, each having 16 channels, allows for control of 48 channels, corresponding to two cooling fans 1057 per reactor 49 of a 48 reactor apparatus (fan pairs are energized together). An exemplary fan control module is the Opto 22 sixteen channel relay board, available from Opto 22 of Temecula, Calif., U.S.A. The cabinet 1085 additionally includes at least one emergency off switch 1141 for terminating power to the apparatus 41, except for the computer, the vent 1117, and the dry box (discussed below). Further details of the foregoing components will not be discussed here, as they will be readily understood by those skilled in the art.
In another example, much of the apparatus 41 and its components discussed above are enclosed by an enclosure (not shown). The enclosure is preferably what is referred to as a “dry box” or a “glove box” having gloves affixed to the periphery of openings in the side walls of the enclosure to allow an operator to manipulate items inside the enclosure and reduce possible contamination. The enclosure can be gas-tight and/or filled with a pressurized inert gas (e.g., argon or nitrogen). In either case, the environment is controlled to eliminate contaminants or other material which might interfere with the parallel reaction processes being conducted in the enclosure. Conventional antechambers (air locks) on the enclosure provide access to the interior of the enclosure. Glove box enclosures suitable for use in the present invention are available from, among others, Vacuum Atmospheres Company of Hawthorne, Calif., and M. Braun Inc. of Newburyport, Mass., U.S.A. Other types of enclosures may also be used, such as a purge box which is movable between a non-enclosing position and an enclosing position and purged of contaminants using a pressurized inert gas.
As described in detail herein and as would be readily understood by one skilled in the art, the following features are contemplated as within the scope of the present invention. In one example, an apparatus for processing of a reaction mixture comprises a spindle including an upper end rotatable in an opening of a bearing hub. In another example, a bearing comprises at least two resilient arms adapted to flex upon placement of the bearing in a vessel. In yet another example, a vessel support and a cap are keyed with respect to one another for orienting the cap with respect to the vessel support. In still another example, a bearing having at least two arms includes support members on the at least two arms for engaging an upper rim of a vessel for locating the bearing in a generally axial direction with respect to the vessel. In a further example, a vessel and a vessel support are keyed with respect to one another for orienting the vessel with respect to the vessel support.
In still another example, a pressurized gas manifold comprises a plurality of pressure relief valves, one valve associated with each of a plurality of first gas conduits, for relieving pressure within a corresponding first gas conduit and reaction chamber, should the pressure exceed a threshold. In a further example, a sealing mechanism cooperates with at least one passage in a cap for maintaining a vessel seal.
In another example, a cap includes at least one heater comprising a cartridge heater received within a cavity of the cap. In a further example, vessels for holding reaction mixtures are each associated with a temperature control jacket operable to control the temperature of the reaction mixture within a respective vessel, and a controller operates the temperature control jackets to control the temperatures of the reaction mixtures in the vessels independent of one another. In another example, a temperature control jacket comprises an electric resistance band heater. In yet another example, an apparatus comprises at least two temperature probes associated with a vessel, whereby one of the at least two temperature probes is operable to sense the temperature of a vessel support, and another of the at least two temperature probes is operable to sense the temperature of the reaction mixture. In still another example, an apparatus includes a cooling assembly comprising at least two cooling fans for blowing cooling air toward a temperature control jacket and a vessel support. The cooling assembly may further comprise a shroud for directing the cooling air toward the temperature control jacket and vessel support.
The apparatus may further comprise other vessels for holding reaction mixtures, other vessel supports adapted for supporting respective other vessels, other temperature control jackets operable to control the temperatures of the reaction mixtures within the respective other vessels, other cooling fans for blowing cooling air toward the other temperature control jackets and the other vessel supports, and other shrouds for directing cooling air toward the other temperature control jackets and the other vessel supports. Each of the shrouds may direct cooling air toward a respective temperature control jacket and vessel support and away from other temperature control jackets and vessel supports. The apparatus may further comprise a controller for controlling the operation of the at least two cooling fans.
In another example, an apparatus comprises a conductivity probe received within at least one passage of a cap for contacting a reaction mixture. The apparatus may also comprise a temperature probe received within at least one passage of the cap for contacting the reaction mixture. The apparatus may also comprise an optical probe received within at least one passage of the cap for measuring a characteristic of the reaction mixture. The apparatus may also comprise a sealing mechanism cooperating with the at least one passage for maintaining a vessel seal.
In another example, the apparatus comprises a vessel having a total volume of between about 10 ml (0.34 oz) and about 80 ml (2.7 oz). The vessel may further have a total volume of between about 10 ml (0.34 oz) and about 50 ml (1.7 oz). The vessel may further have a total volume of between about 12 ml (0.41 oz) and about 40 ml (1.4 oz).
In another example, the apparatus comprises a vessel support, a vessel, and a cap constructed for conducting reactions at gage pressures from about zero kilopascals (kPa) (zero pounds per square inch (psi)) to about 3400 kPa (500 psi). The vessel support, vessel, and cap may be further constructed for conducting reactions at gage pressures from about 340 kPa (50 psi) to about 2800 kPa (400 psi). The vessel support, vessel, and cap may be further constructed for conducting reactions at gage pressures from about 690 kPa (100 psi) to about 2400 kPa (350 psi). The vessel support, vessel, and cap may be further constructed for conducting reactions at gage pressures from about 1400 kPa (200 psi) to about 2100 kPa (300 psi).
In still another example, an apparatus may comprise a vessel having an aspect ratio (L/D) of less than about 4. The vessel may also have an aspect ratio (L/D) of less than about 3. The vessel may also have an aspect ratio (L/D) of less than about 2.
In yet another example, an apparatus comprises a stirrer comprising a first magnetic follower comprising at least two permanent magnets and a second magnetic follower comprising at least two permanent magnets. In another example, the permanent magnets are sealed within a stirring implement. In still another example, an apparatus includes a stirrer comprising flux guide constructed of ferromagnetic material. The flux guide may be constructed of steel. In yet another example, the stirrer may be constructed of a material with a lower magnetic flux permeability than the flux guide. In one example, the stirrer is constructed of stainless steel. In still another example, the stirrer is capable of operation at temperatures from about 0° C. (30° F.) to about 350° C. (660° F.). The stirrer may also be capable of operation at temperatures from about 20° C. (68° F.) to about 200° C. (390° F.). The stirrer may also be capable of operation at temperatures from about 40° C. (100° F.) to about 160° C. (320° F.). In yet another example, the apparatus comprises a magnetic driver configured to rotate a stirrer at speeds from about 0 rpm to about 2000 rpm. The magnetic driver may also be configured to rotate the stirrer at speeds from about 100 rpm to about 1000 rpm. The magnetic driver may further be configured to rotate the stirrer at speeds from about 100 rpm to about 500 rpm.
In another example, an apparatus comprises a bearing received by a vessel within a reaction chamber; a spindle being rotatable in the bearing. In a further example, an apparatus includes a stirrer comprising a magnetic stir bar.
In another example, a stirring system for use in a reactor includes a stirrer comprising first and second magnetic followers, each follower having a magnetic pole axis. An included angle between the magnetic pole axis of the first magnetic follower and the magnetic pole axis of the second magnetic follower is one of less than and equal to about 2.6 radians (150 degrees). The included angle between the magnetic pole axis of the first magnetic follower and the magnetic pole axis of the second magnetic follower may also be one of less than and equal to about 2.1 radians (120 degrees). In another example, the system comprises a magnetic driver framework constructed of a material having a low magnetic flux permeability. The driver framework may be constructed of aluminum. In still another example, a rotatable magnetic driver comprises a first magnetic driver element comprising at least two permanent magnets and a second magnetic driver element comprising at least two permanent magnets. The first and second magnetic driver elements may comprise magnets constructed of at least one of Samarium Cobalt 28 Grade 28, Samarium Cobalt Grade 18, and Samarium Cobalt Grade 20 magnetic materials. In yet another example, a first flux guide is positioned in a driver framework above a first magnetic driver element and a second flux guide is positioned in the driver framework above a second magnetic driver element. The driver framework may further include a first cavity for receiving the first flux guide and a second cavity for receiving the second flux guide. The first cavity and the first flux guide may be keyed with respect to one another for orienting the first flux guide with respect to the driver framework; and the second cavity and the second flux guide are keyed with respect to one another for orienting the second flux guide with respect to the driver framework. In another example, the system comprises flux guides having first and second concave surfaces shaped and sized relative to a bottom surface of a vessel for providing substantially uniform spacing between the concave surfaces and the bottom of the vessel that may range from about 1 mm (0.04 in) to about 10 mm (0.4 in). The spacing may further range from about 2 mm (0.08 in) to about 5 mm (0.2 in). In another example, a vessel has a convex bottom surface facing a flux guide comprising first and second concave surfaces. The concave surfaces may further be spaced a substantially uniform distance from the convex bottom surface of the vessel. In another example, a rotatable magnetic driver comprises first and second flux guides constructed of a ferromagnetic material. The first and second flux guides may be constructed of steel.
In yet another example, the system includes a drive mechanism comprising a drive train comprising a belt and pulley system coupled to drive shafts adapted to couple with respective magnetic drivers. A motor may drive the belt and pulley system to rotate the drive shafts. The drive mechanism may further comprise a gearbox coupled to the motor and to the belt and pulley system for driving the belt and pulley system at a speed different than the speed of the motor. The system may further comprise a controller for controlling the operation of the motor.
In still another example, a stirrer comprises first and second magnetic followers having magnetic pole axes, whereby an included angle between the magnetic pole axis of the first magnetic follower and the magnetic pole axis of the second magnetic follower is one of less than and equal to about 3.1 radians (180 degrees). The included angle may also be one of less than and equal to about 2.6 radians (150 degrees). The included angle may also be one of less than and equal to about 2.1 radians (120 degrees). In another example, a stirrer comprises at least two permanent magnets enclosed by a stirring implement, and wherein a flux guide comprises at least one flux guide element in a passage in the stirrer extending between the permanent magnets. In yet another example, a stirrer comprises at least one stirring element having an inner end adjacent a spindle and an outer end opposite the inner end, wherein the inner end has a smaller cross section than the outer end. In another example, a stirrer comprises at least one stirring element having a substantially airfoil-shaped cross section. The stirrer may also comprise stirring elements creating low shear forces within a reaction mixture in a vessel. In still another example, a stirrer comprises a paddle extending substantially perpendicular to a plane containing stirring elements. The paddle may also comprise at least two substantially planar blades projecting laterally from a spindle in a respective plane. The respective blades may be oriented askew relative a longitudinal axis of the spindle. In another example, a stirrer comprises four mixing arms arranged about every 1.6 radians (90 degrees) around a hub. In still another example, a stirrer comprises a first mixing arm oriented in a first lateral direction enclosing one of at least two permanent magnets and a second mixing arm oriented in a second lateral direction generally opposite the first lateral direction enclosing another of the at least two permanent magnets. In yet another example, a stirrer comprises a spindle and a stirring implement constructed of at least one of a chemically-resistant plastic material and stainless steel. The chemically-resistant plastic material may be at least one of a perfluoro-elastomer, a polyethylethylketone, and a polytetrafluoroethylene.
In another example, an apparatus for processing of reaction mixtures comprises a cap and a head, each having cooperating registration elements for orienting the cap relative to the head wherein said cooperating registration elements include at least two registration elements on the cap and corresponding recesses in the head for receiving the at least two registration elements. In still another example, an apparatus comprises a cap retainer having a twist-lock connection with a head. The twist-lock connection may also comprise a bayonet connection. In yet another example, the apparatus includes an extractor comprising a rod positioned over a cap and attachable to the cap for lifting the cap.
When introducing elements of the present invention or the preferred embodiment(s) thereof, the articles “a”, “an”, “the” and “said” are intended to mean that there are one or more of the elements. The terms “comprising”, “including” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements.
In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained.
As various changes could be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.
| Number | Date | Country | |
|---|---|---|---|
| 60622547 | Oct 2004 | US | |
| 60563759 | Apr 2004 | US |
