Process for hydrocracking hydrocarbon-containing petroleum feeds in the presence of a catalyst comprising at least one NU-85, NU-86 or NU-87 zeolite

Abstract
The invention provides a process for hydrocracking hydrocarbon-containing petroleum feeds in the presence of a catalyst comprising a support containing at least one matrix, and at least one zeolite selected from the group, formed by NU-85, NU-86 and NU-87 zeolites., said catalyst further comprising, at least one metal selected from the group formed by metals from group VIB and VIII of the periodic table, optionally at least one group VIIA element, and optionally phosphorous
Description


[0001] The present invention relates to a process for hydrocracking hydrocarbon-containing feeds in the presence of a catalyst, said catalyst comprising at least one metal selected from the group formed by metals from group VIB and VIII (group 6 and/or groups 8, 9 and 10 in the new periodic table notation: Handbook of Chemistry and Physics. 76th edition, 1995-1996), combined with a support comprising an amorphous or low crystallinity oxide type support and at least one zeolite selected from the group formed by NU-85, NU-86 and NU-87 zeolites. The catalyst optionally comprises phosphorous, and optionally at least one group VIIA element (group 17, the halogens).


[0002] Hydrocracking heavy petroleum feeds is a very important refining process which produces lighter fractions such as gasoline, Jet fuel and light gas oil from surplus heavy feeds which are of low intrinsic value, which lighter fractions are needed by the refiner so that he can match production to demand. Certain hydrocracking processes can also produce highly purified residues which can constitute excellent bases for oils. The importance of catalytic hydrocracking over catalytic cracking is that it can produce very good quality middle distillates, jet fuels and gas oils. With the aid of suitable catalysts, hydrocracking can also produce gasoline with a much lower octane number than that from catalytic cracking, but which in contrast contains much lower amounts of sulphur and impurities than gasoline from catalytic cracking. The octane number of hydrocracked gasoline is then increased by a suitable subsequent reforming treatment.


[0003] Catalysts used for hydrocracking are generally bifunctional, combining an acid function and a hydrogenating function. The acid function is supplied by large surface area supports (150 to 800 m2/g in general) with a superficial acidity, such as halogenated aluminas (in particular fluorinated or chlorinated), amorphous silica-aluminas and zeolites. The hydrogenating function is supplied either by one or more metals from group VIII of the periodic table, such as iron, cobalt, nickel, ruthenium, rhodium, palladium, osmium, iridium or platinum, or by at least one metal from group VI, such as molybdenum, tungsten, or chromium, or by a combination of at least one group VIB metal and at least one metal from group VIII. The optional croup VIIA element is selected from fluorine, chlorine, bromine and iodine.


[0004] The equilibrium between the two, acid and hydrogenating, functions is the fundamental parameter which governs the activity and selectivity of the catalyst. A weak acid function and a strong hydrogenating function produces low activity catalysts which generally operate at a high temperature (390° C. or above), and at a low supply space velocity (HSV, expressed as the volume of feed to be treated per unit volume of catalyst per hour, and is generally 2 or less), but have very good selectivity for middle distillates and thus poor selectivity for gasoline. In contrast, a strong acid function and a weak hydrogenating function produces active catalysts but selectivities for middle distillates are poorer and thus selectivities for gasoline are better. The search for a suitable catalyst is thus centered on the proper choice of each of the functions to adjust the activity/selectivity balance of the catalyst.


[0005] One of the main points of hydrocracking is to exhibit high flexibility at various levels: flexibility in the catalysts used, which results in flexibility in the feeds to be treated and in the products obtained. One parameter which is easy to control is the acidity of the catalyst support.


[0006] The vast majority of conventional catalytic hydrocracking catalysts are constituted by weakly acidic supports such as amorphous silica-aluminas. More particularly, such systems are used to produce very good quality middle distillates and, when their acidity is very low, oil bases.


[0007] Weakly acid supports include amorphous silica-aluminas. Many catalysts on the hydrocracking market are based on silica-alumina combined either with a group VIII metal or, as is preferable when the amount of heteroatomic poisons in the feed to be treated exceeds 0.5% by weight, a combination of sulphides of group VIB and VIII metals. The selectivity for middle distillates of such systems is very good, and the products formed are of high quality. The least acidic of such catalysts can also produce lubricating bases. The disadvantage of all such amorphous support-based catalytic systems is, as already stated, their low activity.


[0008] The catalytic activities of catalysts comprising Y zeolite with structure type FAU or catalysts containing a beta type zeolite are higher than that of amorphous silica-aluminas, and selectivities for light products are higher.


[0009] Research carried out by the Applicant on a number of zeolites and crystalline microporous solids have led to the discovery that, surprisingly, a process for hydrocracking hydrocarbon-containing petroleum feeds in the presence of a catalyst containing at least one zeolite selected from the group formed by NU-NU-85, NU-86 and NU-87 zeolites, at least one metal selected from the group formed by metals from group VIB and group VIII of the periodic table, optionally phosphorous, and optionally at least one element from group VIIA, can achieve higher activities than a process for hydrocracking hydrocarbon-containing petroleum feeds in the presence of prior art catalysts.


[0010] The hydrogenating function is selected from group VIII metals such as iron, nickel, cobalt, platinum, palladium, ruthenium, rhodium, osmium, iridium, and from metals from group VIB, such as chromium, tungsten, or molybdenum.


[0011] The NU-85 zeolite used in this patent has been described in European patent EP-A2-0 462 745, which patent is hereby incorporated into the present description by reference.


[0012] The NU-85 zeolites forming part of the composition of the invention are used with the silica and aluminium contents obtained on synthesis.


[0013] The NU-86 zeolite used in the process of the invention, in its hydrogen form or partially in its hydrogen form, designated H-NU-86 and obtained by calcining and/or ion exchange of as synthesised NU-86, and the method of synthesising said as synthesised NU-86, are described in European patent EP-A2-0 463 768.


[0014] The structure type of this zeolite has not yet been officially attributed by the synthesis commission of the IZA (International Zeolite Association). However, following the work published at the 9th International Zeolite Conference by J. L Casci, P. A. Box and M. D. Shannon (“Proceedings of the 9th International Zeolite Conference”. Montreal 1992, Eds R. Von Ballmoos et al., 1993, Butterworth), it appears that:


[0015] NU-86 zeolite has a three-dimensional microporous system;


[0016] the three-dimensional microporous system is constituted by straight channels with a pore opening which is delimited by 11 T atoms (tetrahedral atoms: Si, Al, Ga. Fe . . . ), straight channels which are alternately delimited by openings with 10 and with 12 T atoms, and sinusoidal channels which are also alternately delimited by openings with 10 and with 12 T atoms.


[0017] The term “pore openings with 10, 11 or 12 tetrahedral atoms (T)” means pores constituted by 10, 11 or 12 sides.


[0018] The NU-86 zeolite used in the composition of the invention is at least in part, preferably almost completely, in its acid form. i.e., in its hydrogen form (H+). The Na/T atomic ratio is generally less than 90% and preferably less then 50%, more preferably less than 10%.


[0019] The NU-87 with structure type NES also used in the present invention has been described in EP-Al-0 377 291 and in the publication “Atlas of Zeolite Structure Types” by W. M. Meier, D. H. Olson and Ch. Baerlocher, Fourth revised edition 1996, Elsevier.


[0020] The NU-85, NU-86 and NU-87 zeolites are preferably at least partially in their acid form (and preferably completely in their H form) or partially exchanged with metal cations, for example alkaline-earth metal cations.


[0021] The NU-85, NU-86 and NU-87 zeolites used in the composition of the invention are used with the silica and aluminium contents obtained on synthesis.


[0022] The catalyst used in the process of the present invention also comprises at least one amorphous or low crystallinity oxide type porous mineral matrix. Non limiting examples are aluminas, silicas and silica-aluminas. Aluminates can also be used. Preferred matrices contain alumina, in any of the forms known to the skilled person, more preferably aluminas, for example gamma alumina.


[0023] The catalyst also optionally comprises phosphorous, optionally at least one group VIIA element, preferably fluorine. The hydrogenating function per se has been defined above. i.e., at least one metal selected from the group formed by group VIB and/or group VIII metals.


[0024] The catalyst used in the process of the present invention generally comprises at least one metal selected from the following groups and with the following contents, in weight % with respect to the total catalyst weight:


[0025] 0.1% to 60%, preferably 0.1% to 50%, more preferably 0.1% to 40%, of at least one metal selected from the group formed by group VIB and group VIII metals;


[0026] 0.1% to 99%, preferably 1% to 99%, of at least one amorphous or low crystallinity oxide type porous mineral matrix:


[0027] 0.1% to 90%, preferably 0.1% to 80%, more preferably 0.1% to 70%, of at least one zeolite selected from the group formed by NU-85, NU-86 and NU-87 zeolites;


[0028] and optionally:


[0029] 0 to 20%, preferably 0 to 15%, more preferably 0.1% to 10%, of phosphorous;


[0030] and optionally again:


[0031] 0 to 20%, preferably 0.1% to 15%, more preferably 0.1% to 10%, of at least one element selected from group VIIA, preferably fluorine.


[0032] The group VIB and group VIII metals in the catalyst used in the process of e present invention can be at least partially in the form selected from the metal id/or oxide and/or sulphide.


[0033] This catalyst of the present invention can be prepared using any of the methods known to the skilled person. Advantageously, it is obtained by mixing the matrix and the zeolite then forming the mixture. The hydrogenating element is introduced during mixing, or, as is preferable, after forming. Forming is followed by calcining, the hydrogenating element being introduced before or after calcining. Preparation is completed by calcining at a temperature of 250° C. to 600° C.


[0034] A preferred method consists of mixing a NU-85, NU-86 or NU-87 zeolite powder in a moist alumina gel for a few tens of minutes, then passing the paste obtained through a die to form extrudates with a diameter in the range 0.4 to 4 mm.


[0035] The hydrogenating function can be introduced at any time and by different methods. Thus, for example, the hydrogenating function can be introduced only partially (in the case, for example of combinations of oxides of groups VIB and VIII metals) or completely on mixing the zeolite with the gel of the oxide selected as the matrix.


[0036] In a further implementation, the hydrogenating function can, for example, be introduced by one or more ion exchange operations carried out on the calcined support constituted by at least one zeolite selected from the group formed by NU-85, NU-86 and NU-87 zeolite, dispersed in the selected matrix, using solutions containing precursor salts of the selected metals when these are group VIII metals.


[0037] Finally, the hydrogenating function can be introduced by at least one operation for impregnating the calcined support constituted by at least one zeolite selected from the group formed by NU-85, NU-86 and NU-87 and the matrix, using solutions containing at least one precursor of at least one oxide of at least one metal selected from the group formed by group VIB and VIII metals, the precursor(s) of at least one oxide of at least one group VIII metal preferably being introduced after those of group VIB or at the same time as the latter, if the catalyst contains at least one group VIB metal and at least one group VIII metal.


[0038] When the elements are introduced in a plurality of steps for impregnating the corresponding precursor salts, an intermediate calcining step must be carried out at a temperature in the range 250° C. to 600° C., and an intermediate catalyst drying step is generally carried out at a temperature generally in the range 60° C. to 250° C.


[0039] The phosphorous, and at least one element selected from the halide ions of group VIIA, can be introduced to the calcined precursor by one or more impregnation steps using an excess of solution.


[0040] Sources of group VIB elements which can be used are well known to the skilled person. Examples of molybdenum and tungsten sources are oxides and hydroxides, molybdic acids and tungstic acids and their salts, in particular ammonium salts such as ammonium molybdate, ammonium heptamolybdate, ammonium tungstate, phosphomolybdic acid, phosphotungstic acid and their salts, silicomolybdic acid, silicotungstic acid and their salts. Preferably, oxides and ammonium salts are used, such as ammonium molybdate, ammonium heptamolybdate and ammonium tungstate.


[0041] The catalyst of the present invention can comprise at least one group VIII element such as iron, cobalt, nickel, ruthenium, rhodium, palladium, osmium, iridium or platinum. The following combinations of metals can be used, for example: nickel-molybdenum, cobalt-molybdenum, iron-molybdenum, iron-tungsten, nickel-tungsten, or cobalt-tungsten. Preferred combinations are: nickel-molybdenum and cobalt-molybdenum. It is also possible to use combinations of three metals, for example nickel-cobalt-molybdenum.


[0042] The sources of the group VIII elements which can be used are well known to the skilled person. Examples of non noble metals are nitrates, sulphates, phosphates, halides, for example chlorides, bromides and fluorides, and carboxylates, for example acetates and carbonates. Examples of sources of noble metals are halides, for example chlorides, nitrates, acids such as chloroplatinic acid, and oxychlorides such as ammoniacal ruthenium oxychloride.


[0043] The preferred phosphorous source is orthophosphoric acid H3PO4, but its salts and esters such as ammonium phosphates are also suitable. Phosphorous can, for example, be introduced in the form of a mixture of phosphoric acid and a basic organic compound containing nitrogen, such as ammonia, primary and secondary amines, cyclic amines, pyridine group compounds, quinolines, and pyrrole group compounds.


[0044] Sources of group VIIA elements which can be used are well known to the skilled person. As an example, fluoride anions can be introduced in the form of hydrofluoric acid or its salts. These salts are formed with alkali metals, ammonium or an organic compound. In the latter case, the salt is advantageously formed in the reaction mixture by reacting the organic compound with hydrofluoric acid. It Is also possible to use hydrolysable compounds which can liberate fluoride anions in water, such as ammonium fluorosilicate (NH4)2SiF6, silicon tetrafluoride SiF4 or sodium fluorosilicate Na2SiF6. Fluorine can be introduced, for example, by impregnating an aqueous hydrofluoride solution or ammonium fluoride.


[0045] The catalysts obtained, in the form of oxides, can optionally be at least partially brought into the metal or sulphide form.


[0046] The catalysts obtained in the present invention are formed into grains of different shapes and dimensions. They are generally used in the form of cylindrical or polylobed extrudates such as bilobes, trilobes, or polylobes with a straight or twisted shape, but they can also be produced and used in the form of compressed powder, tablets, rings, beads or wheels. The specific surface area is measured by nitrogen adsorption using the BET method (Brunauer, Emmett, Teller, J. Am. Chem. Soc., vol. 60, 309-316 (1938)) and is in the range 50 to 600 m2/g, the pore volume measured using a mercury porisimeter is in the range 0.2 to 1.5 cm3/g and the pore size distribution may be unimodal, bimodal or polymodal.


[0047] The present invention concerns the use of the catalysts obtained for hydrocracking hydrocarbon feeds such as petroleum cuts. The feeds used in the process are gasolines, kerosines, gas oils, vacuum gas oils, atmospheric residues, vacuum residues, atmospheric distillates, vacuum distillates, heavy fuels, oils, waxes and paraffins, spent oil, deasphalted residues or crudes, feeds from thermal or catalytic conversion processes, and their mixtures. They contain heteroatoms such as sulphur, oxygen and nitrogen and possibly metals.


[0048] The catalysts obtained are advantageously used for hydrocracking, in particular of vacuum distillate type heavy hydrocarbons, deasphalted residues or hydrotreated residues or the like. The heavy cuts are preferably constituted by at least 80% by volume of compounds with a boiling point of at least 350° C., preferably in the range 350° C. to 580° C. (i.e., corresponding to compounds containing at least 15 to 20 carbon atoms). They generally contain heteroatoms such as sulphur and nitrogen. The nitrogen content is usually in the range 1 to 5000 ppm by weight and the sulphur content is in the range 0.01% to 5% by weight.


[0049] The hydrocracking conditions such as temperature, pressure, hydrogen recycle ratio, and hourly space velocity, can vary widely depending on the nature of the feed, the quality of the desired products and the facilities available to the refiner. The temperature is generally over 200° C. and preferably in the range 250° C. to 480° C. The pressure is over 0.1 MPa and preferably over 1 MPa. The hydrogen recycle ratio is a minimum of 50 and preferably in the range 80 to 5000 normal liters of hydrogen per liter of feed. The hourly space velocity is generally in the range 0.1 to 20 volumes of feed per volume of catalyst per hour.


[0050] The catalysts used in the present invention preferably undergo sulphurisation to transform at least part of the metallic species to the sulphide before bringing them into contact with the feed to be treated. This activation treatment by sulphurisation is well known to the skilled person and can be carried out using any method already described in the literature.


[0051] One conventional sulphurisation method which is well known to the skilled person consists of heating in the presence of hydrogen sulphide to a temperature in the range 150° C. to 800° C., preferably in the range 250° C. to 600° C., generally in a traversed bed reaction zone.


[0052] The catalyst used in the present invention can advantageously be used for hydrocracking vacuum distillate type feeds with high sulphur and nitrogen contents.


[0053] The catalyst of the present invention can be used for hydrocracking under high hydrogen pressure conditions of at least 5 MPa. The treated cuts are, for example, vacuum distillates containing high sulphur and nitrogen contents which have already been hydrotreated. In this case, the petroleum cut conversion process is carried out in two steps, with or without an intermediate separation or distillation operation, the catalyst of the invention being used in the second step.


[0054] The catalyst of the first step can be any prior art hydrotreatment catalyst. It comprises a matrix, preferably based on alumina, and at least one metal with a hydrogenating function. Any hydrotreatment catalyst which is known to the skilled person can be used. The hydro-dehydrogenating function is ensured by at least one metal or metal compound, used alone or in combination, selected from group VIB and group VIII metals such as nickel, cobalt, molybdenum and tungsten. Further, this catalyst may optionally contain phosphorous or boron.


[0055] The first step is generally carried out at a temperature of 350-460° C., preferably 360-450° C., with a pressure of over 3 MPa, an hourly space velocity of 0.1-5, preferably 0.2-2 hand with a quantity of hydrogen of at least 100 NI/NI of feed, preferably 260-3000 NI/NI of feed.


[0056] For the conversion step using the catalyst of the invention (or second step), the temperatures are generally 230° C. or more, usually in the range 300° C. to 480° C., preferably in the range 300° C. to 440° C. The pressure is generally over 5 MPa, preferably over 7 MPa. The quantity of hydrogen is a minimum of 100 I/I of feed, usually in the range 200 to 3000 I/I of hydrogen per liter of feed. The hourly space velocity is generally in the range 0.15 to 10 h.


[0057] Under these conditions, the catalysts used in the present invention have better selectivities for light distillates (gasoline, kerosine) than commercially available catalysts, even with considerably lower zeolite contents than those of prior art catalysts.


[0058] The following examples illustrate the present invention without in any way limiting its scope.






EXAMPLE 1


Preparation of a support containing NU-85 zeolite

[0059] Large quantities of a hydrocracking catalyst support containing a NU-85 zeolite were produced so as to enable different catalysts based on the same support to be prepared. The starting material used was a NU-85 zeolite prepared as described in Example 4 of EP-A2-0 462 745, with a global Si/Al atomic ratio of 13.1 and a Na/Al atomic ratio of 0 23.


[0060] This NU-85 zeolite first underwent dry calcining at 550° C. in a stream of dry air for 20 hours. The solid obtained underwent four ion exchange steps in a solution of 10 N NH4NO3 at about 100° C. for 4 hours for each exchange step. The solid obtained was designated as NH4-NU-85/1 and had an Si/Al ratio of 13.6 and an Na/Al ratio of 0.005. The remaining physico-chemical characteristics are shown in Table 1.
1TABLE 1AdsorptionSBETV(P/P0 = 0.19)Sample(m2/g)ml liquid N2/gNH4-NU-85/14360.18


[0061] 18.6 grams of H-NU-85 zeolite as prepared above was mixed then milled with 81.4 grams of a matrix composed of ultrafine tabular boehmite or alumina gel sold by Condéa Chemie GmblH under the trade name SB3. This powder mixture was then mixed with an aqueous solution containing 66% nitric acid (7% by weight of acid per gram of dry gel) then milled for 15 minutes. After milling, the paste obtained was passed through a die with cylindrical orifices with a diameter of 1.4 mm. The extrudates were then dried and calcined at 500° C. for 2 hours in dry air.



EXAMPLE 2

[0062] Preparation of hydrocracking catalysts containing a NU-8zeolite (in accordance with the invention)


[0063] Extrudates of the support of Example 1 were dry impregnated with a solution of ammonium heptamolybdate and nickel nitrate. and finally calcined at 550° C. in-situ in the reactor. The oxide weight contents of catalyst NU85NiMo obtained are shown in Table 2.


[0064] The support extrudates of Example 1 were dry impregnated with a solution of a mixture of ammonium heptamolybdate, nickel nitrate and orthophosphoric acid, and finally calcined at 550° C. in-situ in the reactor. The oxide weight contents of catalyst NU85NiMoP obtained are shown In Table 2.


[0065] Fluorine was then added to this catalyst by impregnation using a dilute solution of hydrofluoric acid so as to deposit about 1% by weight of fluorine. After drying overnight at 120° C. and calcining at 550° C. for 2 hours in dry air, catalyst NU85NiMoPF was obtained.


[0066] The final oxide contents of the NU85NiMo catalysts are shown in Table 2.


[0067] Extrudates of the support containing a NU-85 zeolite of Example 1 were dry impregnated with an aqueous ammonium heptamolybdate solution, dried overnight at 120° C. in air and finally calcined in air at 550° C. The oxide weight contents of catalyst NU85Mo obtained are shown in Table 3.


[0068] Similarly, extrudates of the support containing a NU-85 zeolite of Example 1 were also dry impregnated with an aqueous solution of ammonium heptamolybdate and phosphoric acid, dried overnight at 120° C. in air and finally calcined in air at 550° C. The oxide weight contents of catalyst NU85MoP obtained are shown in Table 3. Fluorine was then added to this catalyst by impregnation using a dilute solution of hydrofluoric acid so as to deposit about 1% by weight of fluorine. After drying overnight at 120° C. and calcining at 550° C. for 2 hours in dry air, catalyst NU85MoPF was obtained. The final oxide contents of the NU85Mo catalysts are shown in Table 3.
2TABLE 2characteristics of NU85NiMo catalystsCatalystNU85NiMoNU85NiMoPNU85NiMoPFMoO3 (wt %)14.313.713.5NiO (wt %)3.12.92.9P2O5 (wt %)04.84.8SiO2 (wt %)14.413.613.4F (wt %)001.06Complement to 100%68.265.064.2mainly composed ofAl2O3 (wt %)


[0069]

3





TABLE 3










Characteristics of NU85Mo catalysts










Catalyst
NU85Mo
NU85MoP
NU85MoPF













MoO3
14.6
13.95
13.8


(wt %)


P2O5
0
4.8
4.7


(wt %)


SiO2
14.8
14.1
13.7


(wt %)


F
0
0
1.1


(wt %)


Complement to 100%
70.6
67.1
66.1


mainly composed of


Al2O3 (wt %)











EXAMPLE 3


Preparation of a support containing a NU-85 zeolite and a silica-alumina

[0070] We produced a silica-alumina powder by co-precipitation, with a composition of 2% SiO, and 98% Al2O3. A support for a hydrocracking catalyst containing this silica-alumina and the NU-85 zeolite of Example 1 was then produced. To this end, 19.1% by weight of the NU-85 zeolite of Example 1 was mixed with 80.9% by weight of a matrix composed of the silica-alumina as prepared above. This powder mixture was mixed with an aqueous solution containing 66% nitric acid (7% by weight of acid per gram of dry gel) then milled for 15 minutes. After milling, the paste obtained was passed through a die having cylindrical orifices with a diameter of 1.4 mm. The extrudates were then dried overnight at 120° C. and calcined at 550° C. for 2 hours in air.



EXAMPLE 4


Preparation of hydrocracking catalysts containing a NU-85 zeolite and a silica-alumina

[0071] Support extrudates containing a silica-alumina and a NU-85 zeolite from Example 3 were dry impregnated using an aqueous solution of a mixture of ammonium heptamolybdate, nickel nitrate and orthophosphoric acid, dried overnight at 120° C. in air and finally calcined in air at 550° C. The oxide weight contents of catalyst NU85-SiAl-NiMoP obtained are shown in Table 4.


[0072] Fluorine was then added to this catalyst by impregnation using a dilute solution of hydrofluoric acid so as to deposit about 1% by weight of fluorine, After drying overnight at 120° C. and calcining at 550° C. for 2 hours in dry air, catalyst NU85-SiAl-NiMoPF was obtained.


[0073] The characteristics of the NU85-SiAl-NiMo catalysts are shown in Table 4.
4TABLE 4characteristics of NU-85-SiAl-NiMo catalystsCatalystNU85-SiAl-NiMoPNU85-SiAl-NiMoPFMoO3 (wt %)13.513.4NiO (wt %)2.82.8P2O5 (wt %)5.04.95F (wt %)00.84SiO2 (wt %)15.316.5Complement to 100%63.461.5mainly composed ofAl2O3 (wt %)



EXAMPLE 5


Preparation of a support containing NU-86 zeolite

[0074] Large quantities of a hydrocracking, catalyst support containing a NU-86 zeolite were produced so as to enable different catalysts based on the same support to be prepared. The starting, material used was a NU-86 zeolite prepared as described in Example 2 of EP-A2-0 463 768, with a global Si/Al atomic ratio of 10.2 and a Na/Al atomic ratio of 0.25.


[0075] This as synthesised NU-86 zeolite first underwent dry calcining at 550° C. in a stream of dry air for 9 hours. The solid obtained underwent four ion exchange steps in a solution of 10 N NH4NO3 at about I100° C. for 4 hours for each exchange step. The solid obtained was designated as NH4-NU-86/1 and had an Si/Al ratio of 10.4 and an Na/Al ratio of 0.013. The remaining physico-chemical characteristics are shown in Table 5.
5TABLE 5AdsorptionX ray diffractionSBETV(P/P0 = 0.19)SampleCrystallinity (%)(m2/g)ml liquid N2/gNH4-NU-36/11004230.162


[0076] The NU-86 zeolite crystallites were in the form of crystals with a size of 0.4 μm to 2 μm.


[0077] Subsequently, 19.5 g of NH4-NU-86/1 zeolite was mixed with 80.5 g of a matrix composed of ultrafine tabular boehmite or alumina gel from Condéa Chemie GmbH with trade name SB3. This mixture of powder was then mixed with an aqueous solution containing 66% nitric acid (7% by weight of acid per gram of dry gel) then mixed for 15 minutes. The mixed paste was extruded through a 1.2 mm die. The extrudates were calcined at 500° C. for 2 hours in air.



EXAMPLE 6


Preparation of hydrocracking catalysts containing a NU-86 zeolite

[0078] Preparation of example 2 was reproduced, using extrudates of the support of Example 5.


[0079] The final oxide contents of the NU86NiMo catalysts are shown in Table 6. The final oxide contents of the NU86Mo catalysts are shown in Table 7.
6TABLE 6characteristics of NU86NiMo catalystsCatalystNU86NiMoNU86NiMoPNU86NiMoPFMoO3 (wt %)14.113.413.3NiO (wt %)3.23.13.0P2O5 (wt %)04.14.1SiO2 (wt %)14.714.113.9F (wt %)001.0Complement to 100%68.065.364.5mainly composed ofAl2O3 (wt %)


[0080]

7





TABLE 7










characteristics of NU86Mo catalysts










Catalyst
NU86Mo
NU86MoP
NU86MoPF













MoO3
14.5
14.00
13.9


(wt %)


P2O5
0
4.1
4.2


(wt %)


SiO2
15.2
14.6
14.4


(wt %)


F
0
0
1.01


(wt %)


Complement to 100%
70.2
67.3
66.6


mainly composed of


Al2O3 (wt %)











EXAMPLE 7


Preparation of a support containing a NU-86 zeolite and a silica-alumina

[0081] The preparation of Example 3 was reproduced using zeolite NU-86 of Example 5.



EXAMPLE 8


Preparation of hydrocracking catalysts containing a NU-86 zeolite and a silica-alumina

[0082] Preparation of Example 4 was reproduced using support extrudates containing a silica-alumina and a NU-8 zeolite from Example 7.


[0083] The final oxide contents of the NU86-SiAl-NiMo catalysts are shown in Table 8.
8TABLE 8characteristics of NU86-SiAl-NiMo catalystsCatalystNU86-SiAl-NiMoPNU86-SiAl-NiMoPFMoO3 (wt %)13.413.3NiO (wt %)3.03.0P2O5 (wt %)4.24.15F (wt %)00.87SiO2 (wt %)15.615.4Complement to 100%63.963.3mainly composed ofAl2O3 (wt %)



EXAMPLE 9


Preparation of a hydrocracking catalyst support containing a NU-87 catalyst

[0084] The starting material was an NU-87 zeolite with a global Si/Al atomic ratio of 17.2. and a sodium weight content corresponding to a Na/Al atomic ratio of 0.144. This NU-87 zeolite was synthesised as described in EP-A-0 377 291.


[0085] This NU-87 zeolite first underwent dry calcining at 550° C. in a stream of dry air for 6 hours. The solid obtained underwent four ion exchange steps in a solution of 10 N NH4NO3 at about 100° C. for 4 hours for each exchange step. The solid obtained was designated as NH4-NU-87 and had an Si/Al ratio of 17.4 and an Na/Al ratio of 0.002. The remaining physico-chemical characteristics are shown in Table 9.
9TABLE 9X ray diffraction parametersAdsorptionabcβVCryst.(1)SBETV(2)Sample(Å)(Å)(Å)(°)(Å3)(%)(m2/g)NH4-14.3522.3425.14151.5338401004660.19NU-87


[0086]

(1)
Crystallinity; (2) V at P/P0=0.19. in ml liquid N2/g


[0087] A hydrocracking catalyst support containing a NU-87 zeolite was produced as follows: 20% by weight of a NU-87 zeolite was mixed with 80% by weight of type SB3 alumina from Condéa. The mixed paste was extruded through a 1.4 mm die. The extrudates were dried overnight at 120° C. then calcined at 550° C. in air.



EXAMPLE 10


Preparation of hydrocracking catalysts containing a NU-87 zeolite (in accordance with the invention)

[0088] Preparation of Example 2 was reproduced using extrudates of the support of Example 9.


[0089] The final oxide contents of the NU87NiMo catalysts are shown in Table 10. The final oxide contents of the NU87Mo catalysts are shown in Table 11.
10TABLE 10Characteristics of NU87NiMo catalystsCatalystNU87NiMoNU87NiMoPNU87NiMoPFMoO313.913.413.2(wt %)NiO3.33.13.1(wt %)P2O504.354.3(wt %)SiO214.914.214.0(wt %)F000.92(wt %)Complement to 100%67.965.064.3mainly composed ofAl2O3 (wt %)


[0090]

11





TABLE 11










Characteristics of NU87Mo catalysts










Catalyst
NU87Mo
NU87MoP
NU87MoPF













MoO3
14.2
13.6
13.5


(wt %)


P2O5
0
4.3
4.3


(wt %)


SiO2
15.4
14.7
14.6


(wt %)


F
0
0
0.9


(wt %)


Complement to 100%
70.3
67.2
66.6


mainly composed of


Al2O3 (wt %)











EXAMPLE 11


Preparation of a support containing a NU-87 zeolite and a silica-alumina

[0091] Preparation of Example 3 was reproduced using zeolite NU-87 of Example 9.



EXAMPLE 12


Preparation of hydrocracking catalysts containing a NU-87 zeolite and a silica-alumina

[0092] Preparation of Example 4 was reproduced, using support extrudates containing a silica-alumina and a NU-87 zeolite from Example 11.


[0093] The characteristics of the NU87-SiAl-NiMo catalysts are shown in Table 12.
12TABLE 12Characteristics of NU87-SiAl-NiMo catalystsCatalystNU87-SiAl-NiMoPNU87-SiAl-NiMoPFMoO3 (wt %)13.913.3NiO (wt %)3.13.0P2O5 (wt %)4.24.1F (wt %)00.80SiO2 (wt %)16.316.2Complement to 100%63.062.5mainly composed ofAl2O3 (wt %)



EXAMPLE 13


Preparation of a support containing a Y zeolite

[0094] A large quantity of a hydrocracking catalyst support containing a Y zeolite was produced so as to enable different catalysts based on that support to be prepared. To this end, 20.5% by weight of a dealuminated Y zeolite with a lattice parameter of 2.429 nm. a global SiO2/Al2O3 ratio of 30.4 and a framework SiO2/Al2O3 ratio of 58 was mixed with 79.5% by weight of a matrix composed of ultrafine tabular boehmite or alumina gel sold by Condéa Chemie GmbH under the trade name GS3. This powder mixture was then mixed with an aqueous solution containing 66% nitric acid (7% by weight of nitric acid per gram of dry gel) then mixed for 15 minutes. After mixing, the paste obtained was passed through a die having cylindrical orifices with a diameter of 1.4 mm. The extrudates were then dried overnight at 120° C. and calcined in air for 2 hours at 550° C. in moist air containing 7.5% by volume of water. Cylindrical extrudates 1.2 mm in diameter were produced which had a specific surface area of 223 m2/g and a monomodal pore size distribution centered on 10 nm. Analysis of the matrix by X ray diffraction showed that it was composed of low crystallinity cubic gamma alumina and dealuminated Y zeolite.



EXAMPLE 14


Preparation of hydrocracking catalysts containing a Y zeolite (not in accordance with the invention)

[0095] Support extrudates containing a dealuminated Y zeolite from Example 13 were dry impregnated using an aqueous solution of a mixture of ammonium heptamolybdate and nickel nitrate, dried overnight at 120° C. and finally calcined in air at 550° C. The oxide weight contents of catalyst YNiMo obtained are shown in Table 13. The final YNiMo catalyst contained 17.1% by weight of Y zeolite with a lattice parameter of 2.429 nm. a global SiO2/Al2O3 ratio of 30.0 and a framework SiO2/Al2O3 ratio of 57.


[0096] Support extrudates containing a dealuminated Y zeolite from Example 13 were dry impregnated using an aqueous solution of a mixture of ammonium heptamolybdate, nickle nitrate and orthophosphoric acid, dried overnight at 120° C. and finally calcined in air at 550° C. The oxide weight contents of catalyst YNiMoP obtained are shown in Table 13. The final YNiMoP catalyst contained 16.3% by weight of Y zeolite with a lattice parameter of 2.429 nm, a global SiO2/Al2O3 ratio of 30.4 and a framework SiO2/Al2O3 ratio of 58.


[0097] Fluorine was then added to this catalyst by impregnation using a dilute solution of hydrofluoric acid so as to deposit about 1% by weight of fluorine. After drying overnight at 120° C. and calcining at 550° C. for 2 hours in dry air, catalyst YNiMoPF was obtained.


[0098] The final oxide contents of the YNiMo catalysts are shown in Table 13.


[0099] Extrudates of the support containing a dealuminated Y zeolite of Example 13 were dry impregnated with. an aqueous ammonium heptamolybdate solution, dried overnight at 120° C. in air and finally calcined in air at 550° C. to obtain a YMo catalyst. Similarly, extrudates of the support containing a dealuminated Y zeolite of Example 13 were also dry impregnated with an aqueous solution of amnnonium heptamolybdate and phosphoric acid, dried overnight at 120° C. in air and finally calcined in air at 550° C. The oxide weight contents of catalyst YMoP obtained are shown in Table 14. Fluorine was then added to this catalyst by impregnation using a dilute solution of hydrofluoric acid so as to deposit about 1% by weight of fluorine. After drying overnight at 120° C. and calcining at 550° C. for 2 hours in dry air, catalyst YMoPF was obtained.


[0100] The final oxide contents of the YMo catalysts are shown in Table 14.
13TABLE 13characteristics of YNiMo catalystsCatalystYNiMoYNiMoPYNiMoPFMoO313.512.912.8(wt %)NiO3.13.02.9(wt %)P2O504.44.3(wt %)F001.05(wt %)SiO216.215.415.1(wt %)Complement to 100%67.264.363.7mainly composed ofAl2O3 (wt %)


[0101]

14





TABLE 14










characteristics of YMo catalysts












Catalyst
YMo
YMoP
YMoPF
















MoO3
13.4
12.35
12.7



(wt %)



P2O5
0
4.4
4.4



(wt %)



SiO2
16.6
15.9
15.7



(wt %)



F
0
0
1.0



(wt %)



Complement to 100%
70.0
66.8
66.1



mainly composed of



Al2O3 (wt %)












EXAMPLE 15


Comparison of catalysts for hydrocracking of a vacuum gas oil

[0102] The catalysts prepared in the above examples were used under high conversion (60-100%) hydrocracking conditions. The petroleum feed was a hydrotreated vacuum distillate with the following principal characteristics:
15Density (20/4)0.869Sulphur (ppm by weight)502Nitrogen (ppm by weight)10Simulated distillationInitial point298° C.10% point369° C.50% point427° C.90% point481° C.End point538° C.


[0103] This feed had been obtained by hydrotreatment of a vacuum distillate using a HR360 catalyst from Procatalyse comprising a group VIB element and a group VIII element deposited on alumina.


[0104] 0.6% by weight of aniline and 2% by weight of dimethyldisulphide were added to the feed to simulate the partial pressures of H2S and NH3 present in the second hydrocracking step. The prepared feed was injected into the hydrocracking test unit which comprised one fixed bed reactor in upfiow mode, into which 80 ml of catalyst had been introduced. The catalyst was sulphurised using a n-hexane/DMDS+ aniline mixture at 320° C. It should be noted that any in-situ or ex-situ sulphurisation method is suitable. Once sulphurisation had been carried out, the feed described above could be transformed. The operating conditions of the test unit were as follows:
16Total pressure9 MPaCatalyst80 cm3Temperature360-420° C.Hydrogen flow rate80 l/hFeed flow rate80 cm3/h


[0105] The catalytic performances are expressed as the temperature at which a gross conversion of 70% is produced and by the gasoline and jet fuel (kerosine) yields. These catalytic performances were measured for the catalyst after a stabilisation period, generally of at least 48 hours, had passed.


[0106] The gross conversion GC is taken to be:


[0107] GC=weight % of 380° C.minus of effluent.


[0108] 380° C.minus represents the fraction distilled at a temperature of 380° C. or less.


[0109] The (27-150) gasoline yield (hereinafter Gyld) was equal to the weight % of compounds with a boiling point in the range 27° C. to 150° C. in the effluents. The jet fuel yield (kerosine, 150-250) (hereinafter Kyld) was equal to the weight % of compounds with a boiling point in the range 150° C. to 250° C. in the effluents. The (250-380) gas oil yield was equal to the weight % of compounds with a boiling point in the range 250° C. to 380° C. in the effluents.


[0110] The reaction temperature was fixed so as to obtain a gross conversion GC of 70% by weight. Table 15 below shows the reaction temperature and light distillate yields for the catalysts described in the examples above.
17TABLE 15Catalytic activities of hydrocracking catalystsGasoline yieldKerosine yieldT (° C.)(wt %)(wt %)NiMo/Y37520.524.1NiMoP/Y37421.224.7NiMoPF/Y37319.923.6Mo/Y37521.324.3MoP/Y37521.024.1MoPF/Y37519.723.4NiMo/NU-8538624.610.8NiMoP/NU-8538535.111.8NiMoPF/NU-8538434.411.8Mo/NU-8538735.612.8MoP/NU-8538735.711.8MoPF/NU-8538635.712.3NiMoP/SiAl-NU-8538536.513.5NiMoPF/SiAl-NU-8538536.213.7NiMo/NU-8637336.312.3NiMoP/NU-8637136.913.4NiMoPF/NU-8637136.412.8Mo/NU-8637337.213.1MoP/NU-8637337.012.9MoPF/NU-8637336.813.4NiMoP/SiAl-NU-8637237.612.4NiMoPF/SiAl-NU-8637336.912.7NiMo/NU-8738437.512.0NiMoP/NU-8738337.112.2NiMoPF/NU-8738237.011.8Mo/NU-8738537.912.5MoP/NU-8738537.612.5MoPF/NU-8738527.312.8NiMoP/SiAl-NU-8738337.113.2NiMoPF/SiAl-NU-8738436.612.8


[0111] Table 15 demonstrates that the process of the invention using a catalyst comprising a NU-85, NU-86 or NU-87 zeolite leads, for a degree of conversion of 70%, to gasoline yields which are higher than catalysts which are not in accordance with the invention, in particular those based on dealuminated Y zeolite. It should be noted that the gasoline yields were better with the process using a catalyst based on a NU-87 zeolite. Further, the group of catalysts of the invention leads to gasoline and kerosine yields which are improved compared to those recorded in the case of prior art catalysts.


[0112] The preceding examples can be repeated with similar success by substituting the generically or specifically described reactants and/or operating conditions of this invention for those used in the preceding examples. Also, the preceding specific embodiments are to be construed as merely illustrative, and not limitative of the remainder of the disclosure in any way whatsoever.


[0113] The entire disclosure of all applications, patents and publications, cited above and below, and of corresponding French applications 98/02.312 and 98/02.442, are hereby incorporated by reference.


[0114] From the foregoing description, one skilled in the art can easily ascertain the essential characteristics of this invention, and without departing from the spirit and scope thereof, can make various changes and modifications to the invention to adapt it to various usages and conditions.


Claims
  • 1. A process for hydrocracking hydrocarbon-containing feeds in the presence of a catalyst comprising at least one metal selected from the group formed by metals from groups VIB and VIII of the periodic table, at least one matrix and at least one zeolite seleted from NU-85, NU-86 and NU-87 zeolite.
  • 2. A process according to claim 1 in which the catalyst comprises a NU-85 zeolite.
  • 3. A process according to claim 1 in which the catalyst comprises a NU-86 zeolite
  • 4. A process according to claim 1 in which the catalyst comprises a NU-87 zeolite
  • 5. A process according to anyone of claim 1 to 4, characterized in that the catalyst also contains phosphorous.
  • 6. A process according to any one of claim 1 to 5, characterized in that the catalyst also comprises at least one element selected from group VIIA of the periodic table.
  • 7. A process according to any one of claims 1 to 6, in which the catalyst comprises, by weight with respect to the catalyst: 0.1 % to 60% of at least one metal selected from the group formed by group VIB and group VIII metals; 0.1 % to 90% of at least one zeolite selected from NU-85, NU-86 and NT-87 zeolite; 0.1% to 99% of at least one amorphous or low crystallinity mineral matrix; 0 to 20% of phosphorous; 0 to 20% of at least one element selected from group VIIA.
  • 8. A process according to any one of claims 1 to 7, in which a prior catalyst sulphurisation treatment is carried out.
  • 9. A process according to any one of claims 1 to 8, in which the feed is constituted by at least 80% by volume of compounds with a boiling point of at least 350° C.
  • 10. A process according to any one of claims 1 to 9, in which the temperature is over 200° C., the pressure is over 0.1 MPa, the hydrogen recycle ratio is over 50 normal liters of hydrogen per liter of feed, and the HSV is in the range 0. 1 to 20 h−.
  • 11. A process according to any one of claims 1 to 9, in which the temperature is 230° C. or more, the pressure is over 5 MPa, the quantity of hydrogen is over 100 normal liters of hydrogen per liter of feed, and the hourly space velocity is in the range 0.15 to 10 h−.
  • 12. A process according to claim 11, in which a prior hydrotreatment step is carried out at a temperature in the range 350° C. to 460° C., at a total pressure of at least 3 MPa, with an hourly space velocity in the range 0.1 to 5 h31, with a quantity of hydrogen of at least 100 Nl/Nl of feed and in the presence of a hydrotreatment catalyst.
Priority Claims (2)
Number Date Country Kind
98/02.312 Feb 1998 FR
98/02.442 Feb 1998 FR
Continuations (1)
Number Date Country
Parent 09257931 Feb 1999 US
Child 09946726 Sep 2001 US