The present invention relates generally to reactor systems and methods for high throughput screening of materials for desirable characteristics, and in particular to such systems and methods in which the materials are heated and/or cooled by the reactor system.
Research and development programs directed at discovery of materials use high-throughput screening tools to evaluate multiple different candidate materials and/or process conditions to reduce the costs and time associated with the identification of promising candidate materials and/or process conditions. Various high-throughput parallel reactor systems have been developed to evaluate multiple candidate materials and/or process conditions by conducting multiple reactions in parallel (i.e., during the same or overlapping time periods).
Pertinent disclosure of a parallel reactor system suitable for high-throughput experimentation is set forth in U.S. Pat. No. 6,306,658 entitled “Parallel Reactor with Internal Sensing” and issued to Symyx Technologies, Inc., the entire contents of which are hereby incorporated by reference. A reactor corresponding to the '658 patent is commercially available from Symyx Technologies, Inc. of Sunnyvale, Calif. as a Symyx Parallel Pressure Reactor. The Symyx Parallel Pressure Reactor includes a reactor block having a plurality of wells for containing reaction materials for the various reactions. The system also includes temperature, pressure, and other sensors that allow monitoring of the reactions while they are in progress. The reactor block has a high capacity to absorb and retain heat. During the course of many reactions, the reactor block is heated by a temperature control system along with the reaction materials to an elevated temperature. Because the reactor block has a relatively high thermal mass, the reactor block helps the temperature control system maintain the reaction materials at a relatively consistent, temperature despite any exotherms or endotherms associated with the reactions being conducted in the wells. This is advantageous because it helps ensure that the reactions are conducted under process conditions that closely correspond to the process conditions specified in the designs of the experiments.
Reactor systems that have relatively high thermal mass reactor blocks have been satisfactory for numerous applications in many different fields of research. It has been recognized in the art that low thermal mass structures facilitate rapid thermal cycling of reaction materials. However, most parallel reactor systems continue to rely on a relatively high thermal mass structure (such as a reactor block) to help control temperature of the reaction materials. The present inventors have discovered improved systems and methods that facilitate high-throughput experimentation in workflows that call for rapid heating and/or cooling of reaction materials.
One aspect of the present invention is a reactor system. The reactor system has a housing. A plurality of reactors are at least partially contained in the housing. The reactors each have a containment structure enclosing an internal space in the reactor. The containment structure includes a circumferential sidewall having opposite ends and surrounding at least a portion of said internal space. The sidewall has a thermal mass. A sidewall heater is adjacent an exterior surface of the sidewall. A ratio of the thermal mass of the sidewall to a volume of said portion of the internal space that is surrounded by the sidewall is in the range of about 200 kJ/Km3 to about 3000 kJ/Km3.
Other objects and features will in part be apparent and in part pointed out hereinafter.
Corresponding reference characters indicate corresponding parts throughout the drawings.
Referring now to the drawings, first to
The reactors 103 and housing 105 of each reactor assembly 102 are suitably a modular system, e.g., so the housing and reactors can be installed as a module on a robotic workstation 109 (such as a Symyx Core Module from Symyx Technologies, Inc. of Sunnyvale, Calif.), as illustrated in
The reactors 103 are suitably substantially identical to one another, as is the case in the illustrated embodiment. Thus, a detailed description of one reactor 103 will suffice to describe all the reactors. However, it is understood that the reactors can differ from one another in size, shape and/or construction without departing from the scope of the invention.
The reactors 103, which are best illustrated in
The reaction vessels 115 are suitably constructed of one or more materials that are resistant to chemical interactions with the reaction materials to be contained therein. For example, the reaction vessels 115 can be constructed of glass, aluminum, stainless steel, ceramic, titanium, a nickel-based super alloy (e.g., Hastelloy®) or other similar materials. The reaction vessels 115 can be plated with Teflon, Nickel, or other materials if desired. The reaction vessels 115 can optionally be constructed to be interchangeable with other known reactor systems, such as the reactor system described in commonly owned U.S. Pat. No. 6,306,358, for example. For reasons that will become apparent, it is contemplated that it may be desirable in some applications to use very thin liners (such a liner constructed from a metal foil) instead of the reaction vessels 115 that are illustrated in the drawings to minimize the thermal mass of the structures containing the reaction materials. It is understood, however, that the size and shape of the reaction vessels, the material(s) from which they are made, and the wall thickness of the reaction vessels can vary within the scope of the invention.
The reaction vessels 115 are suitably relatively small to facilitate conducting reactions with relatively small quantities of reaction materials. This is desirable for use of the reactor system 101 in various high throughput screening workflows because there can be limited amounts of reaction materials available and/or the reaction materials used in the workflows may be costly. It is also desirable because it allows numerous materials and/or process conditions to be screened in parallel using a relatively small amount of workspace. For example, the cavity 123 defined within each reaction vessel 115 suitably has a total volume in the range of about 500 microliters to about 200 milliliters. Reaction vessels 115 having a relatively small internal cavity 123 as described above are suitable for conducting reactions in which the non-gaseous reaction materials (including any gases dissolved in liquids or other materials in the reaction vessel) have a total volume in the range of about 400 microliters to about 150 milliliters, and more suitably in the range of about 400 microliters to about 40 milliliters, and still more suitably in the range of about 1 milliliter to about 10 milliliters.
Each reactor 103 has a containment structure 141, illustrated in
The containment structure 141 includes a sidewall assembly 151 having a central opening 153 extending generally between opposite ends of the sidewall assembly. A reactor head assembly 201 is at one end (e.g., the upper end) of the sidewall assembly 151. A bottom cap assembly 301 seals the opposite end (e.g., the bottom end) of the sidewall assembly 151. Each of these parts of the containment structure 141 will be described in greater detail below.
The central opening 153 in the sidewall assembly 151 is sized and shaped to extend circumferentially around the internal volume 143 of the reactor 103. In the illustrated embodiment, for example, the sidewall assembly 151 has a generally tubular configuration and the central opening 153 is a generally cylindrical opening that is sized and shaped to receive the reaction vessel. When a reaction vessel 115 or other liner is used, the sidewall assembly 151 is suitably sized and shaped to contact the outer surface of the vessel in conformal relation to facilitate heat transfer between the vessel and sidewall assembly.
The sidewall assembly 151 of the illustrated embodiment includes a lower sidewall 161 and a lower sidewall heater 163 positioned to heat the lower sidewall. The sidewall assembly 151 also includes an upper sidewall 165 and an upper sidewall heater 167 positioned to heat the upper sidewall and headspace 145. Further, the sidewall assembly 151 includes a thermal barrier 171 separating the upper sidewall 165 and upper sidewall heater 167 from the lower sidewall 161 and lower sidewall heater 163.
The lower sidewall 161 is sized and shaped for surrounding at least a portion of the reaction vessel sidewall 117. For example, the lower sidewall 161 of the illustrated embodiment is generally tubular and is sized and shaped so it can be arranged to contact at least a portion of the reaction vessel sidewall 117 in conformal relation. Further, the lower sidewall 161 suitably extends substantially continuously and substantially completely around the perimeter of the reaction vessel sidewall 117. The lower sidewall 161 is suitably positioned to surround at least a portion of any non-gaseous reaction materials contained in the reactor 103 (e.g., at the bottom of the reaction vessel). More suitably, the lower sidewall 161 is sized and positioned to extend from about the bottom of the internal volume 143 of the reactor 103 (e.g., about the bottom 119 of the reaction vessel 115) to at least about the upper surface of any non-gaseous reaction materials to be contained in the reaction vessel 115. In the embodiment illustrated in
The lower sidewall 161 is suitably longer than the upper sidewall 165. For example, the lower sidewall 161 suitably extends from one end of the sidewall assembly 151 at least about 60 percent of the way to the opposite end of the sidewall assembly. The ratio of the length L1 of the lower sidewall 161 to the length L2 of the upper sidewall 165 is suitably in the range of about 1:1 to about 5:1, and more suitably in the range of about 1.5:1 to about 5:1. The lower sidewall 161 suitably has a length L1 in the range of about 1 cm to about 10 cm. The ratio of the internal diameter D1 of the lower sidewall 161 to the length L1 of the lower sidewall is suitably relatively low, which results in a geometry that can facilitate heat transfer between the lower sidewall and the portion of the internal volume 143 of the reactor 103 surrounded by the lower sidewall. For example, the ratio of the internal diameter D1 of the lower sidewall 161 to the length L1 of the lower sidewall is suitably in the range of about 0.1:1 to about 1:1, more suitably in the range of about of about 0.2:1 to about 1:1, and still more suitably in the range about 0.25:1 to about 1:1.
The lower sidewall 161 is also suitably relatively thin and has a relatively low thermal mass. For example, the lower sidewall 161 suitably has a wall thickness T1 in the range of about 0.1 millimeters to about 5 millimeters. The lower sidewall 161 is suitably about as thin as it can be without reducing its strength below what is needed to withstand the maximum pressure difference it will be exposed to in use. The thinness of the lower sidewall 161 helps minimize the thermal mass of lower sidewall. The lower sidewall 161 can also be constructed of a material (e.g., aluminum) having a relatively low volumetric heat capacity and relatively high thermal conductivity to help minimize its thermal mass and thermal time constant. For higher temperature applications, it may be desirable to use stainless steel, a high temperature superalloy (e.g., Hastelloy), or a similar material that retains structural integrity at higher temperatures better than aluminum even though such materials may have a higher heat capacity and/or a lower thermal conductivity. The thermal mass of the lower sidewall 161 is suitably in the range of about 0.5 J/K to about 50 J/K. The ratio of the thermal mass of the lower sidewall 161 to the volume of the portion of the internal volume 143 of the reactor between the ends of the lower sidewall is suitably in the range of about 200 kJ/Km3 to about 3000 kJ/Km3. The ratio of the thermal mass of the lower sidewall 161 to the total internal volume 143 of the reactor 103 is suitably in the range of about 100 kJ/Km3 to about 1500 kJ/Km3.
The upper sidewall 165 is positioned to extend around at least a portion of the reactor head space 145. For example, the upper sidewall 165 suitably extends axially from slightly below the open top 121 of the reaction vessel 115 to above the top of the reaction vessel. As illustrated in
The construction of the upper sidewall 165 can be similar to the construction of the lower sidewall 161. For example, the cross sectional size and shape of the upper sidewall 165 can be substantially similar (if not identical) to the cross sectional size and shape of the lower sidewall 161. The same materials that are suitable for the lower sidewall 161 are also suitable for the upper sidewall 165. Thus, the upper sidewall 165 can be made from the same material as the lower sidewall 161. Like the lower sidewall 161, the upper sidewall 165 suitably has a wall thickness T2 in the range of about 0.1 mm to about 5 mm. It is suitable for the wall thickness T2 of the upper sidewall to be substantially the same as the wall thickness T1 of the lower sidewall 161. However, it is possible that the upper and lower sidewalls 161, 165 differ in cross section size and/or shape, are made from different materials and/or have different wall thicknesses without departing from the scope of the invention.
The thermal mass of the upper sidewall 165 is suitably in the range of about 0.25 J/K to about 25 J/K. The ratio of the thermal mass of the upper sidewall 165 to the portion of the internal volume 143 of the reactor that is between the ends of the upper sidewall is suitably in the range of about 100 kJ/Km3 to about 1500 kJ/Km3. The ratio of the thermal mass of the upper sidewall 165 to the total internal volume 143 of the reactor is suitably in the range of about 50 kJ/Km3 to about 750 kJ/Km3.
The upper and lower sidewall heaters 163, 167 suitably include one or more resistive heating elements in proximity to the outer surfaces of the upper and lower sidewalls 161, 165, respectively. The sidewall heaters 163, 167 are suitably arranged so heat from the heaters flows into the containment structure 141 from multiple radial directions. As illustrated in
The upper and lower sidewall heaters 163, 167 are suitably independently controllable (e.g., by a processor 191) to allow differential heating within the reactor 103. For example, the upper and lower sidewall heaters 163, 167 allow differential heating of the non-gaseous reaction materials in the reactor 103 (e.g., in the cavity 123 of the reaction vessel 115) and the headspace 145. The sidewall heaters 163, 167 suitably also have a relatively low thermal mass to facilitate cooling of the reactor 103 by a cooling system 401 that will be described in more detail later herein. The heaters 163, 167 for each reactor are also suitably independently controllable from the heaters in the other reactors. This allows the reaction materials and/or headspace 145 of one or more of the reactors 103 to be maintained at different temperatures and/or heated at different temperature ramp rates in comparison to the other reactors.
The lower sidewall heater 163 suitably extends from at least about the bottom 119 of the reaction vessel 115 to at least about the level of any non-gaseous reaction materials to be contained in the reaction vessel. More suitably, the lower sidewall heater 163 extends from at least about the bottom 119 of the reaction vessel 115 to at least about halfway between the bottom of the reaction vessel and the top 121 of the reaction vessel. Still more suitably, the lower sidewall heater 163 extends from at least about the bottom 119 of the reaction vessel 115 to a level on the reaction vessel that is at least about three quarters of the way from the bottom of the reaction vessel to the top 121. In the illustrated embodiment, for example, the lower sidewall heater 163 extends all the way from the bottom 119 of the reaction vessel 115 (e.g., slightly below the bottom of the reaction vessel and slightly above the bottom of the lower sidewall 161) to about the bottom of the relatively narrower mouth 127 at the top of the reaction vessel.
The lower sidewall heater 163 suitably has a length L3 in the range of about 0.25 centimeters to about 10 centimeters, and more suitably in the range of about 0.5 centimeters to about 10 centimeters, and still more suitably in the range of about 1 centimeter to about 10 centimeters. The lower sidewall heater 163 suitably extends from about one end (e.g., the bottom end in the orientation as illustrated) of the sidewall assembly 151 at least part of the way to the opposite end of the sidewall assembly. The lower sidewall heater 163 suitably has a length L3 that is in the range of about 25 percent to about 100 percent of the length L1 of the lower sidewall. The lower sidewall heater 163 illustrated in
The lower sidewall heater 163 is suitably a relatively high power heater. For example, the lower sidewall heater 163 suitably has a maximum power output in the range of about 0.06 W/cm2 to about 3.8 W/cm2, wherein the units of area correspond to the external surface area of the lower sidewall 161 that is between the axial ends of the heater. The total power output of the lower sidewall heater 163 when operating at full power is suitably in the range of about 5 W to about 300 W. The power output of the lower sidewall heater 163 is suitably substantially uniform along its axial length. However the power output of the heater 163 can vary as function of axial position within the scope of the invention. The lower sidewall heater 163 can rapidly heat the lower sidewall 161 and the portion of the internal volume 143 of the reactor between the opposite ends of the lower sidewall heater (and any reaction materials contained therein) because of the relatively high power of the lower sidewall heater, because the heater is positioned to circumscribe the lower sidewall 161 and transfer heat into the reactor in substantially multiple (e.g., substantially all) radial directions, and because of the thinness and low thermal mass of the lower sidewall. The thermal mass of the lower sidewall heater 163 itself is suitably in the range of about 15 J/K to about 40 J/K.
The upper sidewall heater 167 suitably has an axial length L4 that is in the range of about 25 percent to about 100 percent of the length L2 of the upper sidewall 165. In the illustrated embodiment, for example, the upper sidewall heater 167 is about coextensive in axial length with the upper sidewall 165. The axial length L4 of the upper sidewall heater 167 is suitably no longer than (e.g., shorter than) the axial length L3 of the lower sidewall heater 163. For example, the ratio of the axial length L4 of the upper sidewall heater 167 to the axial length L3 of the lower sidewall heater 163 is suitably in the range of about 0.1:1 to 1:1, and more suitably in the range of about 0.2:1 to 1:1. The axial length L4 of the upper sidewall heater 167 is suitably about 20 to about 50 percent of the length L5 of the sidewall assembly. The length L4 of the upper sidewall heater 167 is suitably in the range of about 0.25 cm to about 10 cm.
The upper sidewall heater 167 suitably has a maximum power output in the range of about 0.06 W/cm2 to about 6.8 W/cm2, wherein the units of area correspond to the external surface area of the upper sidewall 165 between the axial ends of the upper sidewall heater 167. The total power output of the upper sidewall heater 167 when operating at full power is suitably in the range of about 2 W to about 150 W. The upper sidewall heater 167 can rapidly heat the upper sidewall 167 and heat the reactor headspace 145 because of the relatively high heater power of the upper sidewall heater, because the heater is positioned to circumscribe the upper sidewall and transfers heat into the reactor in multiple (e.g., substantially all) radial directions, and because of the thinness and low thermal mass of the upper sidewall 165. The thermal mass of the upper sidewall heater 167 is suitably in the range of about 6 J/K to about 20 J/K.
Because the heaters 163, 167 are on the exterior surface of the sidewalls 161, 165 and not in the internal space of the reactors, the heaters are not in direct contact with the reaction materials, which facilitates the ability to heat the reaction materials rapidly without producing high thermal gradients (particularly highly localized thermal gradients) in the reaction materials compared with a similar reactor that has a heater in direct contact with the reaction materials. Further, the heaters 163, 167 do not take up any internal space 143 of the reactor. This can suitably translate to a reduction in the size of the sidewall assembly and a corresponding reduction in the thermal mass of the various parts of the sidewall assembly without reducing the reactor's capacity to hold reaction materials.
The purpose of the thermal barrier 171 is to inhibit conductive heater transfer between the upper and lower sidewalls 161, 165. This improves the ability to maintain and control a temperature difference between the upper portion of the reactor (including at least part of the reactor head space 145) and the lower portion of the reactor (e.g., including any non-gaseous reaction materials the reactor 103). The configuration of the thermal barrier 171 can vary within the scope of the invention. For example, rather than having an upper and lower sidewall in spaced relation to one another, the containment structure can include one continuous sidewall made of a material having a relatively low thermal conductivity (e.g., in the range of about 10 to about 20 W/mK) and the upper and lower sidewall heaters can be spaced from one another on the sidewall such that they are insulated from one another by a portion of the relatively non-conductive sidewall.
The thermal barrier 171 illustrated in
The thermal barrier 171 is suitably generally at the same or a similar axial position in the reactor 103 as the mouth 127 of the reaction vessel 115 to facilitate maintaining and controlling a temperature difference between the head space 145 of the reactor and any reaction materials contained in the reaction vessel 115. Although the thermal barrier 171 illustrated in the drawings is a unitary structure, it is contemplated that two or more separate structures can be arranged to be a thermal barrier within the scope of the invention.
Referring to
The entire sidewall assembly 151, which in the illustrated embodiment includes the upper and lower sidewalls 161, 165, the upper and lower sidewall heaters 163, 167, and the thermal barrier 171, suitably has a relatively low thermal mass. For example, the thermal mass of the sidewall assembly 151 is suitably in the range of about 0.5 J/K to about 55 J/K. The ratio of the thermal mass of the sidewall assembly 151 to the volume of the portion of the internal volume 143 of the reactor that is between the opposite ends of the sidewall assembly is suitably in the range of about 0.15 J/Kcm3 to about 3.5 J/Kcm3. It will be appreciated that this ratio is also relatively low due in large part to the relatively low thermal mass of the sidewall assembly 151.
The bottom cap assembly 301 illustrated in
Each reactor 103 desirably includes a pressure sensor operable to monitor pressure in the internal space 143 by monitoring a pressure-induced strain in the containment structure 141. In the illustrated embodiment, for example, the bottom cap assembly 301 includes a pressure sensor 321 operable to detect and monitor the pressure of the internal space 143 inside the containment structure 141. As illustrated in
As illustrated in
Because the pressure sensor 321 is outside the internal space 143 of the containment structure 141, any wiring associated with the pressure sensor does not need to extend through the containment structure. Another advantage of using a pressure sensor 321 that is integrated into the containment structure 141 (e.g., on the outer surface of the containment structure) is that this reduces the influence of the pressure sensor on heating and cooling of reaction materials in the reactor compared with prior art pressure sensors that are positioned within the internal space of the reactor. It also reduces cold spots and dead volume in the reactor. Using a pressure sensor 321 to measure strain in the reactor containment structure 141 also helps in scaling down the reactor system 101 down to a size that is conducive for use in high-throughput screening. Similarly, locating the pressure sensor 321 and rupture disk 315 in the bottom cap assembly 301 also helps scale down the reactor system to a size that is suitable for high-throughput screening methods.
The pressure sensor 321 can be inside the containment structure 141 (e.g., adhered to the inner surface of the thin-walled section 327) or elsewhere on the inner or outer surface of the containment structure within the scope of the invention. Although the pit 325 for the strain gauge 321 is positioned at the bottom of the containment structure 141 in the bottom cap assembly 301 in the illustrated embodiment, the pressure sensor could be located elsewhere within the scope of the invention. Suitable strain gauges for monitoring pressure in the containment structure 141 are commercially available from Vishay Micro-Measurements, which has a place of business in Shelton, Conn.
An inward facing channel 335, illustrated in
There is tolerance for a relatively large range of thermal masses for the bottom cap assembly 301 and head assembly 201 (
The head assembly 201 suitably has a relatively high thermal mass, which can be advantageous for some applications because it results in the head assembly moderating the headspace temperature while the reaction materials are subjected to high heating and cooling temperature ramp rates. For example, the head assembly 201 can have a relatively high thermal mass in the range of 0.5 J/K to about 150 J/K. The ratio of the thermal mass of the head assembly 201 to the thermal mass of the sidewall assembly 151 is suitably in the range of about 1:1 to about 3:1.
As illustrated in
The head assembly 201 has a cannula passage (
At least part of the reactor head 203 is suitably positioned between the ends of the upper sidewall heater 167. Thus, the reactor head 203 can readily be heated by the upper sidewall heater 167 and the heated upper sidewall 165. As illustrated in
The head assembly 201 suitably includes a latching system 251 (e.g., a bayonet style latch) or other fastening system for releasably holding the reactor head 203 in place. As illustrated in
The retainer 253, which in the illustrated embodiment is at the top of the reactor 103, has flats 271 and slots 273 on its sides to facilitate turning the retainer with an unlatching tool 275 (
The retainer 253 also has openings 285 in its upper surface. Each opening 285 is configured to receive one of a plurality of prongs 287 on the tool 275 when the arms 277 of the tool are received in the slots 281. The arms 277 and prongs 287 are secured to a shaft 289 that can be rotated, e.g., by a person grasping a handle (not shown), so the arms and prongs of the tool 275 rotate the retainer 253 to release it from the housing 105 in order to access the interior of the reactor 103 and/or remove the reactor from the housing 105.
It is understood that suitable containment structures may have additional parts and/or may omit some of the parts listed above without departing from the scope of the invention. For example, the thermal barrier can be omitted and a unitary sidewall used instead of the upper and lower sidewalls of the illustrated embodiment. Also, the various parts of the containment structure may have different shapes and may be configured differently than in the illustrated embodiment without departing from the scope of the invention.
The system also includes a cooling system 401 (
As illustrated in
Referring to
As illustrated in
The exhaust manifold 441 of the cooling system 401 in the illustrated embodiment is substantially identical to the supply manifold 421 except that it is axially aligned with the one or more outlets 413 instead of the one or more inlets 411 and is connected to a line 465 to an exhaust. Thus, it is not necessary to describe the exhaust manifold 441 of the cooling system 401 separately. It is understood, however, that the supply and exhaust manifolds may differ from one another within the scope of the invention. It is also understood that other manifolds and systems other than manifolds (e.g., a plurality of fluid lines plumbed to the reactors) can be used to supply cooling fluid to the cooling jackets and exhaust the cooling fluid therefrom within the scope of the invention. It is also contemplated that a cooling fluid can be added to a cooling jacket to cool one or more reactors robotically or manually (e.g., using a syringe) to quickly cool reaction materials.
As noted previously, the reactor head assembly 201 allows addition and/or withdrawal of one or more materials from the reactor 103 via a cannula passage 211 extending through the head assembly. The system 101 also includes a fluid transport system 501 for supplying each of the reactors with one or more fluids (e.g., gaseous reaction materials or inert gases) during the course of a reaction. The fluid transport system 501 (
The fluid transport system 501 is suitably also operable to vent effluent from the headspace 145 of each reactor during a reaction. Effluent vented from the internal volume 143 of the reactors 103 can be directed to an effluent sink 551 or if desired delivered to an analytic instrument (not shown), such as a gas chromatograph, liquid chromatorgraph, mass spectrometer, etc., for example, that is operable to analyze the reactor effluent to assess one or more characteristics of the reactions being conducted in the reactors. The fluid transport system 501 suitably allows each reactor 103 to be vented independently from the other reactors. The fluid transport system 501 can suitably be operated to deliver effluent from each reactor 103 in series to the analytic instrument for analysis. Further, the pressure in one or more reactors 103 can be reduced by venting effluent through the fluid transport system without reducing the pressure in one or more other reactors.
As best illustrated in
Another conduit 541 (
As is best understood in reference to
The reactor openings 111 in the housing 105 extend through the manifold plate 561, as illustrated in
The various annular fluid distribution channels 521, 571 of the fluid transport system 501 operate to permit tolerance for variations in the rotational orientation of the various parts of the reactor 103 in a manner that is substantially analogous to the way the annular channels 433 of the cooling system operate. These channels 521, 571, 433 substantially eliminate to the need to worry about rotational alignment of the various parts of the reactors 103. As long as there is substantial alignment in the axial direction, changes in the rotational orientation of the reactor and/or its various components will not disrupt operation of the cooling system 401 or fluid transport system 501.
It is understood that any of the inward facing channels could be combined with and/or replaced by outwardly facing channels (and vice-versa) within the scope of the invention. Further, it is contemplated that the reactor system 101 can be adapted to use substantially different fluid transport systems within the scope of the invention. For example, the number and configuration of conduits in the manifolds 563, 565 can vary within the scope of the invention. For example, the openings in the manifold plate 561 and/or the one or more conduits can be arranged differently to accommodate an array of reactors having a configuration different from the array of the illustrated embodiment. It is also understood that other manifolds and systems other than manifolds (e.g., a plurality of hoses or other conduits) can be used to feed fluids to the reactors and/or vent the reactors.
The reactor system 101 suitably includes a stirring system 701 operable to stir reaction mixtures in the reactors 103. As illustrated in
To operate the reactor system 101, a relatively small amount of reaction materials (e.g., no more than about 150 milliliters for each reactor) is loaded into the internal spaces 143 of the reactors 103. The reaction materials suitably have a relatively high thermal mass relative to the sidewall assembly 151 and lower sidewall 161. For example, the ratio of the thermal mass of the lower sidewall 161 to the thermal mass of the reaction materials is suitably in the range of about 0.1 to about 10 and more suitably in the range of about 0.3 to about 3. The ratio of the thermal mass of the sidewall assembly 161 to the thermal mass of the reaction materials is suitably in the range of about 0.15 to about 15, and more suitably in the range of about 0.5 to about 5.
After the reaction materials are in the reactors 103, the head assemblies 201 are latched to the manifold cap 261 using the latching system 251 to enclose the reaction materials in the reactors. The fluid transport system is suitably used to pressurize the reactors 103 (e.g., with a process or inert gas). Because each reactor 103 has its own set of valves 585 they can be pressurized to different pressures. The valves 585 can suitably all be closed to seal each reactor 103 if that is desired. However, the independent operation of the valves provides the option to feed fluid (e.g., a reactant, an inert gas, or a quenching fluid) to any one or more reactors in parallel (continuously or intermittently) or in series one after the other.
The reaction materials are heated by the lower sidewall heater 163. Desirably, the reaction materials can be heated rapidly, e.g., at a ramp rate that is suitably at least about 5 degrees C. per minute, and more suitably in the range of about 5 degrees C. per minute to about 25 degrees C. per minute, still more suitably in the range of about 10 degrees C. per minute to about 25 degrees per minute, still more suitably in the range of about 15-25 degrees C. per minute, and still more suitably up to about 100 degrees C. per minute.
While the reaction materials are heated, the cooling system 401 suitably pumps cooling fluid through the cooling jackets 403 of the reactors. The rate of cooling fluid flow through the cooling jackets 403 is suitably relatively high. For example, the cooling system suitably pumps in the range of about 0.15 to about 5 scfm of cooling gas (e.g., chilled nitrogen) to each cooling jacket 403. The cooling fluid suitably contacts the heaters 163 directly in the cooling jacket. Because of their relatively high power and because they heat the reaction materials from multiple radial directions, the heaters 163 are able to heat the reaction materials rapidly in spite of cooling by the cooling system. Further, because the cooling system 401 contacts the relatively low thermal mass sidewall assembly 151 directly with the cooling fluid, the system 101 can quickly cool the reaction materials. For example, if an exotherm in one of the reactors 103 causes the temperature of the reaction materials to exceed the intended temperature, the power to the heater can be reduced (e.g., by the processor 191) to allow the cooling system 401 to rapidly cool the reaction materials to the intended temperature. The power consumed by the heater 163 can also be monitored to determine a rate of conversion for the reaction. If desired for certain reactions involving gas phase reaction materials, the power consumed by the heater 163 and the gas uptake can be monitored to provide two separate indicators of conversion of the reaction.
When the heater 163 is off, the cooling system 401 is suitably able to cool the reaction materials at a rate of at least about 5 degrees C. per minute and more suitably in the range of about 5 degrees C. per minute to about 25 degrees C. per minute, still more suitably in the range of about 10 degrees C. per minute to about 25 degrees per minute, still more suitably in the range of about 15-25 degrees C. per minute, and still more suitably up to about 100 degrees C. per minute.
At any time during operation of the reactor system 101, the upper sidewall heaters 167 can be operated independently of the lower sidewall heaters 163 to control a temperature of the head space for one or more reactors 103 to have a temperature that is different than a temperature of the reaction materials in the respective reactor. For example, in some applications it may be desirable to operate the upper sidewall heaters 167 to heat the headspace 145 to a temperature that is higher than the temperature of the reaction materials to minimize condensation on the reactor head 203. In other applications, particularly those in which the reaction materials are heated to a temperature that is above the temperature that can be withstood by the valve assembly 215, it may be desirable to operate the upper sidewall heater 167 at lower power (or leave it off) to maintain the temperature of the reactor head 203 at a lower temperature than the reaction materials. In either case, the thermal barrier helps maintain the difference in temperature between upper and lower portions of the reactor by limiting conductive heat transfer between the upper and lower sidewalls 161, 165.
The temperature sensor 801 and pressure sensor 321 are suitably used to monitor the temperature of the reaction materials and the pressure inside the reactor 103 while reactions are conducted in the reactor system 101. The temperature sensor 801 suitably measures the temperature of an external surface of the lower sidewall 161 or lower sidewall heater 163 to avoid the need for a temperature sensor in the internal space 143 of the reactor 103. Because the temperature sensor is positioned in axial alignment with the reaction materials and because of the relatively low thermal mass of the sidewall assembly 151 (particularly, the lower sidewall 161) the temperature measured by the sensor 801 corresponds well with the actual temperature of the reaction materials. As the pressure in the reactor 103 changes the thin-walled section 327 in the bottom cap 303 will flex and strain. These pressure induced variations in the strain of the thin-walled section 327 are detected by the strain gauge 321.
It may be desirable in some cases to use the temperature sensor 801 in combination with another temperature sensor (not shown) positioned in direct contact with the reaction materials. For example, the data from a temperature sensor (e.g., thermocouple) positioned in the reaction materials can be used by the processor 191 to control operation of the lower sidewall heater 163 and cooling system 401 to match the temperature of the lower sidewall 161 to the temperature of the reaction materials in order to operate the reactor under substantially adiabatic conditions. It will be appreciated that the thermal response time of the sidewall assembly 151, including the thermal response of the lower sidewall 161, can be relatively quick. This is in part because of the relatively low thermal mass of the sidewall assembly 151 (and lower sidewall 161). This is also in part because the lower sidewall heater 163 and cooling jacket 403 substantially surround the reactor and heat and cool surround the reactor, respectively, from multiple radial directions.
If the temperature or pressure in one or more the reactors 103 is too high for the particular experiment (or for safety reasons), the processor 191 suitably causes the corresponding valve 585 to open to vent the reactor, thereby reducing pressure and temperature in the reactor. The gas uptake of the reactor can be monitored if desired to assess conversion of the reaction. The processor 191 can also operate the valves 585 to supply a partial vacuum to any one or more of the reactors 103 to lower pressure in the reactor according to an experimental protocol that calls for a reduction in pressure during a reaction. Likewise, the processor 191 can suitably operate the valves 585 to send effluent from one or more of the reactors 103 in series to an analytical instrument.
Because the reactor system 101 provides flexibility to subject the reaction materials to a wide range of process conditions, it is feasible to conduct many different types of reactions in the reactor system. For example, the reaction system 101 is suitable for conducting one or more reactions in the following non-limiting list of reactions polymerization reactions, condensation reactions, hydrogenation reactions, reduction reactions (including but not limited to those involving hydrogen), oxidation reactions (including but not limited to those involving oxygen, air or the like), hydrolysis reactions and organic or inorganic synthesis reactions. Reactions may be mono- or multi-phasic, homogeneous or heterogeneous, catalytic or stoichiometric in nature.
Many variations are contemplated as being feasible for some applications and within the scope of the invention. Some non-limiting examples of other embodiments will be discussed to illustrate the breadth of the invention.
Another embodiment of reactor system 1001 is illustrated in
The reactor 3003 illustrated in
The reactor 4003 illustrated in
A reactor that has a sidewall assembly 151 substantially similar to the reactor 103 described above and illustrated in
A resistive heating element was placed into the reactor described for Example 1. The upper and lower sidewall heaters 163, 167 were operated to maintain the temperature of the a solution in the reactor at about 100 degrees C. while the cooling system was operated to flow a cooling gas (e.g., chilled nitrogen) through the cooling jacket 403. The heating element was turned on so that about 1 W of heat was generated in the solution by the heater. Then the heater was turned off. The process was repeated with the heater operating at about 2 W and also at about 3 W.
This example illustrates the thermal response of a reactor constructed in accord with
Without the cooling system, a temperature increase of 11.7° C. was measured in the solution of the reactor of the present invention and this translated to a 2.6° C. temperature increase at the wall of the reactor. When the cooling gas was used, a temperature difference of similar magnitude (12.9° C.) was observed in the solution and a temperature difference of 2.0° C. (from 50.3° C. to 52.3° C.) was observed at the wall of the reactor. The simulated exotherms for the various reactors were observed by the drop in heater power to compensate for the increase in temperature inside the reactor. The power consumption by the heater was higher when the cooling system was operating, but the drop in heater power in response to the simulated exotherm is similar to what occurred without the cooling system.
Solvents loss experiments were conducted to compare solvent loss in reactors having a cold finger as illustrated in
The data indicate that a substantial amount of solvent was recovered in the reactors that had a cold finger. When similar experiments are run with reactors that do not have a cold finger there is substantially more solvent loss due to condensation that is not refluxed back into the reactor vessel. For example, even when the headspace of a reactor lacking a cold finger is heated above the temperature of the lower portion of the reactor, solvent losses in the range of 6-32 percent have been experienced.
The experiment was performed to demonstrate use of a reactor constructed in accord with the embodiment illustrated in
This example is just one example the wide variety of processes that can be conducted using reactor systems of the present invention. It is understood that other processes can be conducted within the scope of the invention.
When introducing elements of the present invention or the preferred embodiments 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 and methods without departing from the scope of the invention, it is intended that all matter contained in the above description and shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.