HYDRODISINTEGRATION CATALYST CONTAINING BETA ZEOLITES AND ZEOLITES AND, AND PROCESS FOR USING IN THE PRODUCTION OF DISTILLATES FIELD OF THE INVENTION The present invention relates to catalyst compositions and their use in hydrocarbon conversion processes, particularly hydrodisintegration. More specifically, the present invention relates to a catalyst composition comprising a Y zeolite and a beta zeolite as active components of disintegration. The present invention relates specifically to a hydrodisintegration process that produces middle distillates. BACKGROUND OF THE INVENTION Petroleum refiners often produce desirable products such as turbosine, diesel and other liquid hydrocarbons known as middle distillates, as well as lower boiling liquids such as naphtha and gasoline, by hydrodisintegrating a hydrocarbon feedstock derived from crude oil. . Hydrodisintegration also has other beneficial results, such as removing sulfur and nitrogen from the feed through hydrotreating. The feed charges that are most frequently subject to hydrodisintegration are diesel and heavy gas oil recovered from crude oil by distillation.
Hydrodisintegration is generally carried out by contacting, in a suitable reactor vessel, diesel fuel or other hydrocarbon feedstocks with a suitable hydrodisintegration catalyst under appropriate conditions, including an elevated temperature and high pressure, and the presence of hydrogen, to produce an overall product of lower average boiling point that contains a distribution of desired hydrocarbon products by the refiner. Although the operating conditions in a hydrodisintegration reactor have some influence on the product yield, the hydrodisintegration catalyst is a major factor in determining these yields. The hydrodisintegration catalysts are subject to an initial classification based on the nature of the predominant decay component of the catalyst. This classification divides the hydrodisintegration catalysts into those based on an amorphous disintegration component such as silica-alumina, and those based on a zeolitic disintegration component such as zeolite beta or Y. Hydrodegradation catalysts are also subject to classification based on the product predominantly desired to be obtained from these, where the two main products are naphtha and "distilled", a term that in the technique of refining by hydrodisintegration refers to
distillate oil derived from fractions whose boiling range is higher than that of naphtha. Distillate typically includes products recovered in a refinery, such as kerosene and diesel. Currently, the distillate is in great demand. For this reason, refiners have focused on hydrodisintegration catalysts that selectively produce a fraction of distillate. The three main catalytic properties with which the operation of a hydrodisintegration catalyst is evaluated to produce a distillate are activity, selectivity, and stability. The activity can be determined by comparing the temperatures at which various catalysts must be used, under otherwise constant hydrodisintegration conditions with the same feed load, to produce a given percentage, typically 65 percent, of products that boam in the range desired, that is, less than 371 ° C for the distillate. The lower the temperature required for a given catalyst, the more active the catalyst is in relation to a catalyst that requires a higher temperature. The selectivity of the hydrodisintegration catalysts can be determined during the activity test described above, and measured as a percentage of the fraction of the product that boils over the range of the desired distillate, ie from 149 to 371 ° C. Stability is a
measure of the degree to which a catalyst maintains its activity for a prolonged period, when treating a hydrocarbon feedstock given the conditions of the activity test. Stability is usually measured in terms of the change in temperature required per day to maintain a given conversion of 65 percent, or different. Although the disintegration catalysts for producing distillates are known and used in commercial environments, there is always a demand for new hydrodisintegration catalysts of selectivity higher than a given activity, or an activity greater than a given selectivity for producing distillates. SUMMARY OF THE INVENTION It has been found that hydrodisintegration catalysts containing a Y zeolite with a unit cell size or dimension ao between 24.25 and 24.32 angstroms and containing a beta zeolite, preferably with a molar ratio of silica to alumina (S1O2) against A1203) less than 30, and an SF6 adsorption capacity of at least 28 percent of the weight (hereinafter referred to as% of the weight), have significantly improved the selectivity to a given activity and have significantly improved activity at a selectivity given, compared to other hydrodisintegration catalysts commercially available today to be used
in hydrodisintegration processes to produce distillates. The catalyst also contains a metallic hydrogenation component such as nickel, cobalt, tungsten, molybdenum or any combination thereof. The catalyst contains from 2 to up to 5% by weight of zeolite beta based on the combined weight of the zeolite beta, the zeolite Y, and the support based on the dry weight, and the catalyst has a weight ratio of zeolite Y against beta zeolite from 2.5 to 12.5 based on dry weight. Y zeolite has a general molar ratio of silica versus alumina of between 5.0 and 11.0. In other embodiments, the catalyst does not contain additional zeolites, or does not contain zeolite beta or zeolite Y. In one embodiment, the catalyst consists of, or essentially consists of, a hydrogenation component, a beta zeolite with a general molar ratio of silica against alumina of less than 30, and an SF6 adsorption capacity of at least 28% by weight, a Y zeolite with a unit cell size of 24.25 to 24.32 angstroms, and a support, where the zeolite Y has a general molar ratio of silica against alumina from 5.0 to 11.0, where the catalyst contains from more than 2% by weight to when more 5% by weight of zeolite beta, based on the combined weight of the zeolite beta, the zeolite Y and the support based on the dry weight, and where the catalyst has a weight ratio
of zeolite Y against beta zeolite from 2.5 to 12.5 based on dry weight, and where zeolite Y has a surface area of less than 800m2 / g. It is thought that a hydrodisintegration catalyst containing this beta zeolite and this Y zeolite is new in the art. Under typical hydrodisintegration conditions, including elevated temperature and pressure and the presence of hydrogen, these catalysts are highly effective for converting diesel and other hydrocarbon feed charges to products of lower average boiling point and lower average molecular weight. In one embodiment, the product contains a relatively large proportion of components that boil in the range of distillates, which is defined herein as being between 149 and 371 ° C. INFORMATION DISCLOSURE Y and beta zeolites have been proposed in combination as components of various catalysts, including hydrodisintegration catalysts. For example, U.S. Pat. 5,275,720, 5,279,726 and 5,350,501 disclose hydrodisintegration processes using a catalyst comprising a beta zeolite and a Y zeolite. 5,350,501 describes a hydrodisintegration process using a catalyst comprising, among other components, a zeolite beta and a zeolite Y with
a unit cell size between 24.25 and 24.35 angstroms, and a water vapor sorption capacity at a partial water vapor pressure of 4.6 and 25 ° C lower than 8.0 percent of the weight of the zeolite. US-A1-2004 / 0152587 discloses a hydrodisintegration catalyst comprising a carrier comprising a zeolite with the faujasite structure with a unit cell size in the range of 24.10 to 24.40 angstroms, a ratio of silica to alumina of more than 12, and a surface area of at least 850 m2 / g, and the catalyst can contain a second zeolite such as zeolite beta, zeolite ZSM-5 or a zeolite Y with a different unit cell size. Two different Y zeolites have been proposed in combination as components of several different catalysts, including hydrodisintegration catalysts, as described in U.S. Pat. 4,661,239 and 4,925,546. DETAILED DESCRIPTION OF THE INVENTION The process and composition disclosed herein can be used to convert a feedstock containing organic compounds into products, particularly by acid catalysis, such as hydro-disintegrating organic compounds, especially hydrocarbons, into a lower boiling product. medium and lower molecular weight. The composition, which can be a catalyst or catalyst support, comprises a beta zeolite and a
Y zeolite. The composition may also comprise a refractory inorganic oxide. When used as a hydrodisintegration catalyst, the composition contains a beta zeolite, a Y zeolite, a refractory inorganic oxide, and a hydrogenation component. The hydrodisintegration process and composition disclosed herein is focused on using a catalyst containing a particular beta zeolite and a particular Y zeolite. Preferably, the composition does not contain additional zeolites, does not contain additional beta zeolite, or does not contain additional Y zeolite. The zeolite beta preferably has a relatively low molar ratio of silica to alumina and a relatively high SF6 adsorption capacity. Y zeolite has a unit cell size between 24.25 and 24.32 angstroms. It has been found that different operating results occur when this zeolite beta and these Y zeolites are incorporated in hydrodisintegration catalysts in this way. In comparison with catalysts containing one or two Y zeolites, the selectivity of products that boil in the range of distillates is greater than a given activity, or the activity is greater than a given product selectivity that bubbles in the range of the distillates. Beta zeolite is well known in the art, as a component of hydrodisintegration catalysts.
The zeolite is described in U.S. Pat. No. 3,308,069 and the reissue in the USA. No. 28341, which are hereby incorporated by reference in their entirety. The zeolite beta used in the process and composition disclosed herein has a molar ratio of silica to alumina of less than 30 in one embodiment, less than 25 in another embodiment, more than 9 and less than 30 in another embodiment, more than 9 and less than 25 in another modality more, more than 20 and less than 30 in another modality, or more than 15 and less than 25 in another modality more. As used herein, and unless otherwise indicated, the molar ratio of silica to alumina (SiO2 versus A1203) of a zeolite is the molar ratio determined on the basis of the total or general amount of aluminum and silica (structural and non-structural) present in the zeolite, and to what is sometimes referred to herein as the general molar ratio of silica to alumina (Si02 to AI2O3). Beta zeolite is generally synthesized from a reaction mixture containing a template agent. The use of template agents to synthesize zeolite beta is well known in the art. For example, U.S. Pat. No. 3, 308, 069 and its re-issue in the USA. No. 28341 describe the use of tetraethylammonium hydroxide, and U.S. Pat. No. 5,139,759, which is incorporated herein by reference in its entirety, describes the use of the tetraethylammonium ion
of the corresponding tetraethylammonium halide. Another conventional method for preparing beta zeolite is described in the book entitled Verified Synthesis of Zeolitic Materials, by H. Robson (editor) and KP Lillerud (XRD standards), second revised edition, ISBN 0-444-50703-5, Elsevier, 2001 It is thought that the choice of a particular template agent is not of critical importance for the success of the process that is revealed in the present. In one embodiment, the zeolite beta is calcined in air at a temperature of between 500 and 700 ° C for a sufficient time to remove the template agent from the beta zeolite. The calcination to remove the template agent can be carried out before or after combining the beta zeolite with the support or the hydrogenation component. Although it is thought that the template agent could be removed at calcination temperatures of more than 700 ° C), too high calcination temperatures could significantly decrease the SF6 adsorption capacity of the beta zeolite. For this reason, it is thought that calcination temperatures of more than 750 ° C should be avoided to remove the template agent when preparing the beta zeolite for use in the process disclosed herein. For the process disclosed herein it is critical that the SF6 adsorption capacity of the zeolite beta be at least 28% by weight. While it is known to steam treat a zeolite
As beta produces changes in the crystal structure of zeolite, the capabilities of current analytical technology have not made it possible to accurately monitor or characterize these changes in terms of the most important structural details of zeolite. Instead, measurements of various physical properties of the zeolite are used, as a surface area, to indicate the changes occurred and the degree of these changes. For example, it is thought that a reduction in the ability of the zeolite to adsorb sulfur hexafluoride (SF6) after being steam treated is caused by a reduction in the crystallinity of the zeolite or in the size or accessibility of the micropores of the zeolite. zeolite However, what may be undesirable is an indirect correlation of the changes in the zeolite, since the adsorption capacity of SF6 in the catalyst used in the process and composition disclosed herein is relatively high. In the embodiments of the process and composition disclosed herein, the SF6 adsorption capacity of the zeolite beta, steam treated or not, should be at least 28% by weight. Accordingly, the beta zeolite of the process and composition disclosed herein can be characterized in terms of SF6 adsorption. There is a recognized technique for the characterization of microporous materials such as zeolites. It is similar to other measurements of adsorption capacity, such as the capacity of
water, in the sense that it uses weight differences to measure the amount of SF6 adsorbed by a sample that has been pretreated to be essentially free of the adsorbate. In this test SF6 is used since its size and shape prevents its entry into pores with diameters less than 6 angstroms. Accordingly, it can be used as a measurement of pore entries and shrinkage of pore diameters. This, in turn, is a measurement of the effect of the steam treatment on the zeolite. In a simplistic description of this measurement method, preferably the sample is first vacuum pre-dried at 300 ° C for one hour, then heated at atmospheric pressure in air at 650 ° C for two hours, and finally weighed. Then it is exposed to SF6 for one hour, keeping the sample at a temperature of 20 ° C. The vapor pressure of SF6 produced by liquid SF6 at 400 torr (53.3 kPa) is maintained. The sample is then reweighed to measure the amount of SF6 adsorbed. You can suspend the sample on a scale during these steps, to facilitate them. In any mass production process involving techniques such as heating and steam treatment there is the possibility that some particles are subjected to different levels of treatment. For example, particles at the bottom of a pile moving through a rotary kiln may not be subject to the same atmosphere
or temperature that the particles that cover the top of the pile. It is necessary to consider this factor during production, as well as during the analysis and testing of the finished product. Therefore, it is recommended to perform any test measurement of the material in a composite sample representative of the entire quantity of finished product, to avoid confusion with measurements made with individual particles or with a non-representative sample. For example, an adsorption capacity measurement is performed on a representative composite sample. Although the process and composition disclosed herein may utilize a beta zeolite not subject to steam treatment, the process and composition disclosed herein may also utilize a beta zeolite that has been subjected to steam treatment, as long as the treatment is relatively mild compared to the steam treatment of zeolite beta that is described in the literature. Under the appropriate conditions and for the appropriate time, the steam treatment of zeolite beta can produce a catalyst that can be used in the process and composition disclosed herein. The hydrothermal treatment of zeolites for use in hydrodisintegration catalysts is a relatively imprecise tool. For any zeolite
Given, the steam treatment decreases the acidity of the zeolite. When the steam-treated zeolite is used as a hydrodisintegration catalyst, the apparent result is that it increases the general yield of the distillates, but the activity of the catalyst decreases. This apparent balance between performance and activity has meant that obtaining high activity means not steaming beta zeolite, although at the expense of lower product yield. This apparent balance between performance and activity should be considered, and is a limit to the improvement that appears to be obtained by steam treatment of zeolite beta. When the steam-treated zeolite beta is used in the catalysts disclosed herein, the improvement in activity relative to the catalysts containing only Y zeolite would seem limited, while the increase in yield with respect to such catalysts would appear to be improved. If the zeolite beta is steamed, it can be effectively carried out in different ways, and the method that is used is often influenced and sometimes dictated by the type and capacity of the available equipment. The steam treatment can be carried out by keeping the beta zeolite as a fixed mass, or by confining the beta zeolite in a container or by stirring it while it is confined in a rotary kiln. The most important factors are a uniform treatment of all the particles of zeolite beta under appropriate conditions of
time, temperature and concentration of steam. For example, zeolite beta should not be placed under conditions where there is a significant difference in the amount of vapor contacting the surface and the interior of the zeolite beta mass. Beta zeolite can be steam-treated in an atmosphere with live steam passing through the equipment, providing low vapor concentration. This could be described as a vapor concentration of a positive amount of less than 50 mol%. Steam concentrations can vary from 1 to 20 mol%, or from 5 to 10 mol%, with small-scale laboratory operations extending to higher concentrations. The steam treatment may be carried out for a positive period less than or equal to 1 or 2 hours, or for 1 to 2 hours at a temperature less than or equal to 600 ° C at atmospheric pressure and with a positive vapor content less than or equal to 5 % molar. The steam treatment can be carried out for a positive period less than or equal to 2 hours at a temperature less than or equal to 650 ° C at atmospheric pressure and with a positive vapor content less than or equal to 10 mol%. The content of the steam is based on the weight of the vapors that contact the beta zeolite. Steam treatment at temperatures above 650 ° C appears to produce a beta zeolite which is not useful in the process disclosed herein, since the SF6 adsorption capacity of the resulting zeolite beta is too low. They can be used
temperatures of less than 650 ° C, and the temperature of the steam treatment can be 600 to 650 ° C, or less than 600 ° C. It is taught in the art that there is usually an interaction between the time and temperature of the steam treatment, where an increase in temperature reduces the time required. However, if the steam treatment is carried out, it seems that a lapse of between ½ to 2 hours or 1 to 1½ hours can be used to obtain good results. The method for carrying out steam treatment on a commercial scale can be with a rotary kiln to which steam is injected at a rate that maintains an atmosphere of 10 mol% vapor. An exemplary steam treatment on a laboratory scale is to put the zeolite in a 6.4 cm quartz tube in an oven. A controller slowly increases the oven temperature. When the temperature of the zeolite reaches 150 ° C, steam, generated by deionized water contained in a flask, is allowed to enter the bottom of the quartz tube, and then pass upwards. Another gas can be passed to the tube to obtain the desired vapor content. The flask can be refilled as necessary. In the exemplary process, the time elapsed between closing the steam passage and the zeolite reaching 600 ° C is one hour. At the end of the period set for the steam, the temperature in the oven is reduced, setting the controller back to
° C. The oven is allowed to cool to 400 ° C (about 2 hours), and the flow of steam to the quartz tube is stopped. The sample is removed at 100 ° C, and placed in a laboratory oven maintained overnight at 110 ° C, with an air purge. The beta zeolite of the process and composition disclosed herein is not treated with an acid solution to effect the dealuminization. In this regard, it is noted that. essentially all the synthesized beta zeolite is exposed to an acid to reduce the concentration of alkali metal (ie sodium), but not during the synthesis. This step in the production process of the zeolite beta is not considered part of the treatment of the zeolite beta produced as described herein. In one embodiment, during the treatment and catalyst manufacturing processes, zeolite beta is exposed to an acid only during incidental production activities, such as peptization during formation or during metal impregnation. In another embodiment, the beta zeolite is not washed with acid after steam treatment to remove aluminum "debris" from the pores. A Y zeolite with a unit cell size between 24.25 and 24.32 angstroms is also included in the process and composition disclosed herein. The zeolite Y preferably has a unit cell size between 24.26 and 24.30 angstroms. Y zeolite can have a
general mole ratio of silica versus alumina between 5.0 and 12.0 in one modality, from 5.0 to 11.0 in another modality, and from 5.0 to 10.0 in another modality. The process and composition disclosed herein requires a Y zeolite. As the term "Y zeolite" is used herein, it encompasses all crystalline zeolites with the powder X-ray diffraction pattern described in US Pat. .US. No. 3, 130, 007, or a Y zeolite modified with a powder X-ray diffraction pattern similar to that of U.S. Pat. No. 3, 130, 007 although with the separations "d" slightly displaced due to, and as will be understood by those skilled in the art, cation exchanges, calcinations, etc., which are generally necessary to convert the Y zeolite to a catalytically form active and stable. The Y zeolites are Y zeolites modified in comparison to the Y zeolite disclosed in U.S. Pat. No. 3,130,007. As used herein, the term "unit cell size" means the unit cell size determined by powder X-ray diffraction. The Y zeolites used in the process and composition disclosed herein are large pore zeolites with an effective pore size of more than 7.0 angstroms. Since some of the pores of the Y zeolites are relatively large, the Y zeolites allow the
molecules · a relatively free access to its internal structure. The pores of the Y zeolites allow the passage inside them of benzene molecules and larger molecules, as well as the passage from their interior of reaction products. A group of zeolites Y that can be used in the process and composition disclosed herein includes zeolites sometimes designated as ultra-stable or ultra-idrophobic zeolites. In essence, the composition and properties of this group of Y zeolites are prepared by a four-step process. First, a Y-zeolite in the form of an alkali metal (usually sodium) and with a typical unit cell size of 24.65 angstroms exchanges cations with ammonia ions. The ammonia exchange step typically reduces the sodium content of the initial sodium Y zeolite, from a value of more than 8% by weight, usually from 10 to 13% by weight, calculated as Na20, to a value in the range of 0.6 to 5% of the weight, calculated as a20. Methods for carrying out ion exchange are well known in the art. Second, the zeolite Y of the first step is allowed to calcinate in the presence of water vapor. For example, zeolite Y is calcined in the presence of at least 1.4 kPa (absolute) (hereinafter kPa (a)), at least 6.9 kPa (a), or at least 69 kPa (a) of water vapor, in three modalities. In two other embodiments, the Y zeolite is calcined in a
atmosphere that consists essentially of steam. Y zeolite is calcined to produce a unit cell size in the range of 24.40 to 24.64 angstroms. Third, the Y zeolite of the second step returns to make an exchange with ammonia. The second ammonia exchange further reduces the sodium content to less than 0.5% by weight, usually less than 0.3% by weight, calculated as Na20. Fourth, the zeolite Y of the third step receives yet another treatment to produce Y zeolite with a unit cell size of 24.25 to 24.32 angstroms, or preferably 24.26 to 24.30 angstroms. The Y zeolite resulting from the fourth step has a general silica to alumina molar ratio of 5.0 to 12.0 in one embodiment, 5.0 to 11.0 in another embodiment, and 5.0 to 10.0 in another embodiment. The fourth step treatment may comprise any of the well-known techniques for dealuminizing zeolites in general, and ultra-stable Y zeolite in particular, to produce the desired unit cell size and the molar ratio of silica to general alumina. The fourth treatment step may change the unit cell size or the structural molar ratio of silica to alumina, with or without change in the molar ratio of silica to alumina. Generally, desaluminization of zeolite is obtained by chemical methods such as acid treatments, by
example, HC1, with volatile halides, for example, SiCl4, or with chelating agents such as ethylenediaminetetraacetic acid (EDTA). Another common technique is a hydrothermal treatment of the zeolite in pure steam or in air / steam mixtures, preferably as calcining in the presence of sufficient water vapor (for example, in an atmosphere consisting essentially of steam, and more preferably consisting of steam ), to produce the desired unit cell size and the general molar ratio of silica to alumina. The method of preparing zeolites Y discussed above that is used in the process and composition disclosed herein differs from the process for zeolites Y disclosed in U.S. Pat. No. 3,929,672, in the addition of the fourth treatment step. U.S. Pat. No. 3,929,672, which is hereby incorporated by reference in its entirety, discloses a method for dealuminizing an ultra-stable Y zeolite. U.S. Pat. No. 3,929,672 discloses a preparation process in which a sodium Y zeolite partially exchanges ions with ammonia, followed by steam calcination at controlled temperature and partial steam pressure, followed by another exchange with ammonia, and finally an optional step of calcination in a dry atmosphere. The steam exchange and calcination steps can be repeated to obtain the desired degree of dealuminization and reduction in the
unit cell size. The zeolites of U.S. Pat. No. 3,929,672 are known under the designation Y-84 or LZY-84, commercially available from UOP LLC, Des Plaines, Illinois, USA. The Y-84 or LZY-84 zeolites can be produced by the first three mentioned steps, although optionally an additional calcination step can be included in a dry atmosphere, that is, a calcination in free air of water and steam, at 482 ° C or more. The method of preparing zeolites Y used in the process and composition disclosed herein is different from the process for zeolites Y disclosed in U.S. Pat. No. 5,350,501, by the conditions in the fourth treatment step that produces critical ranges of unit cell size for the Y zeolite. No. 5,350,501, which is incorporated herein by reference in its entirety, discloses a fourth step involving calcining the zeolite resulting from the third treatment step in the presence of sufficient water vapor (in an atmosphere consisting essentially of steam or consisting of in steam) to produce a unit cell size of less than 24.40, and more preferably no more than 24.35 angstroms, and with a relatively low water vapor sorption capacity. The Y zeolite produced by the four-step process in U.S. Pat. No. 5,350,501 is a Y UHP zeolite, an ultrahydrophobic Y zeolite as defined in the patent
from the USA No. 5,350, 501. U.S. Pat. No. 5,350,501 defines a "Y-UHP" zeolite as zeolitic aluminosilicates having, among other properties, a unit cell size or dimension of less than 24.45 angstroms, and a water vapor sorption capacity at 25 ° C and a value p / po of 0.10 less than 10.00 percent of the weight. The most preferred zeolite Y UHP in U.S. Pat. No. 5,350, 501 is LZ-10. Another group of zeolites Y that can be used in the process and composition disclosed herein can be prepared by dealuminizing a Y zeolite with a general molar ratio of silica versus alumina less than 5, and which is described in detail in U.S. Pat. Nos. 4,503,023, 4,597,956 and 4,735,928, which are hereby incorporated by reference in their entirety. U.S. Pat. No. 4,503,023 discloses another method for dealuminizing a Y zeolite which involves contacting the Y zeolite with an aqueous solution of a fluorosilicate salt using proportions, temperatures, and controlled pH conditions that prevent the extraction of aluminum without silica replacement. U.S. Pat. No. 4,503,023 specifies that the fluorosilicate salt is used as the aluminum extractant and also as the external source of the silica which is inserted into the structure of the zeolite Y instead of the extracted aluminum. The salts have the formula
general: (A) 2 / bSiF6 Where A is a metallic or non-metallic cation other than H + and with valence "b". The cations represented by "A" are alkylammonia, NH4 +, Mg ++, Li +, Na +, K +, Ba ++, Cd ++, Cu ++, H +, Ca ++, Cs \ Fe ++, Co ++, Pb ++, Mn ++, Rb \ Ag +, Sr ++, Ti + and Zn ++. A preferred member of this group is known as LZ-210, an aluminosilicate zeolite molecular filter commercially available from UOP LLC, Des Plaines, Illinois, USA. The zeolites LZ-210 and the other zeolites of this group are conveniently prepared from an initial material of zeolite Y. The zeolite LZ-210 has a general molar ratio of silica to alumina of 5.0 to 12.0 in one embodiment, from 5.0 to 11.0 in another modality, and from 5.0 to 10.0 in another modality. The unit cell size may preferably be from 24.25 to 24.32 angstroms or more, and preferably from 24.26 to 24.30 angstroms in the case of the Y zeolite I. In the case of the Y II zeolite, the unit cell size may be 24.33. at 24.38 angstroms, or preferably from 24.34 to 24.36 angstroms. The LZ-210 class of zeolites used in the process and composition disclosed herein has a composition expressed in terms of molar ratios of oxides as in the following formula: (0.85-l.l) M2 / nO: Al203: xSi02
Where "M" is a cation with valence "n", and "x" has a value of 5.0 to 12.0. In general, LZ-210 zeolites can be prepared by dealuminizing Y-type zeolites using an aqueous solution of a fluorosilicate salt, preferably a solution of ammonia hexafluorosilicate. The dealuminization can be obtained by placing a Y zeolite, usually but not necessarily a Y zeolite exchanged with ammonia, in an aqueous reaction medium as an aqueous solution of ammonium acetate, and slowly adding a solution of ammonia fluorosilicate. After proceeding with the reaction, a zeolite is produced with a general molar ratio of silica versus increased alumina. The magnitude of the increase depends at least in part on the amount of fluorosilicate solution contacted with the zeolite, and on the allowed reaction time. Normally, a reaction time of between 10 and 24 hours is enough to achieve equilibrium. The resulting solid product, which can be separated from the aqueous reaction medium by conventional filtration techniques, is a form of zeolite LZ-210. In some cases, this product can be steam roasted by methods well known in the art. For example, the product can be contacted with steam at a partial pressure of at least 1.4 kPa (a) for a period of between 3 hours at a temperature of 482 and 816 ° C, in order to provide a
greater crystalline stability. In some cases, the steam calcining product can be subjected to an ammonia exchange by methods well known in the art. For example, the product can be mixed with water, after which an ammonium salt is added to this slime. Typically, the resulting mixture is heated for a few hours, filtered and rinsed with water. Methods of steam treatment and ammonia exchange of zeolite LZ-210 are described in U.S. Pat. Nos. 4,503, 023, 4,735,928 and 5,275,720. The Y zeolites prepared with the preparation methods discussed above and used in the process and composition disclosed herein have an essential X-ray powder diffraction pattern of zeolite Y, and a unit cell size or dimension of from 24.25 to 24.32. angstroms, preferably from 24.26 to 24.30 angstroms. The zeolite Y may have a general molar ratio of silica versus alumina of 5.0 to 12.0 in one embodiment, 5.0 to 11.0 in another embodiment, and 5.0 to 10.0 in another embodiment. The zeolite Y can have a surface area (BET) of at least 500 m2 / g, less than 800 m2 / g, frequently less than 700 m2 / g, and typically from 500 to 650 m2 / g. Another method to increase the stability or acidity of the zeolites Y is by exchanging the Y zeolite with polyvalent metal cations, as cations containing
rare earths, magnesium or calcium cations, or a combination of ammonia ions and polyvalent metal cations, thus reducing the sodium content until they are like the values previously described after the first or second step of exchange with ammonia. Methods for carrying out ion exchange are well known in the art. The catalyst used in the process disclosed herein is to be used primarily as a replacement catalyst in commercially available hydrodisintegration units. Accordingly, its size and shape is preferably similar to those of conventional commercial catalysts. Preferably it is produced in the form of a cylindrical extrudate with a diameter of 0.8 to 3.2 mm. However, the catalyst can be produced in any other desired form, such as a sphere or granule. The extrudate may have other forms besides the cylindrical one, such as the well-known trilobal form or another form having advantages in terms of less diffusional distance or pressure drop. Commercial hydrodisintegration catalysts contain various non-zeolitic materials. This is due to several reasons, such as particle resistance, cost, porosity and performance. Therefore, the other components of the catalyst make positive contributions
to the catalyst in general, even if it is not as active components of disintegration. These other components are designated in the present "support". Some traditional components of the support, such as silica-alumina, normally make some contribution to the catalyst's disintegration capacity. In embodiments of the process and composition disclosed herein, the catalyst has a relatively low content of beta zeolite. The catalyst contains from more than 2% to more 5% by weight, preferably more than 2% by weight, by more than 3% by weight, of beta zeolite, based on the combined weight of the zeolite beta, the zeolite Y and the support, all this in dry weight. As used herein, dry weight is considered as the weight after heating in dry air at 500 ° C for 6 hours. The catalyst has a weight ratio of zeolite Y against beta zeolite of 2.5 to 12.5, preferably from 2.5 to 3.0, of dry weight. The rest of the catalyst particles in addition to the zeolitic material may be composed primarily of conventional hydro-disintegration materials such as alumina or silica-alumina. The presence of silica-alumina helps to achieve the desired performance characteristics for the catalyst. In one embodiment, the catalyst contains at least 25% of the alumina weight and at least 25% of the silica-alumina weight, both based on the combined weight of the
zeolites and support, all based on dry weight. In another embodiment, the silica-alumina content of the catalyst is greater than 40% by weight, and the alumina content of the catalyst is greater than 20% by weight, both based on the combined weight of the zeolites and the support, all This is based on dry weight. However, it is thought that alumina functions only as a binder, and that it is not an active component of disintegration. The catalyst support may contain more than 50% of the weight of silica-alumina or more than 50% of the weight of alumina, based on the dry weight of the support. In one embodiment approximately equal amounts of silica-alumina and alumina are used. Other inorganic refractory materials that can be used as support in addition to silica-alumina and alumina include, for example, silica, zirconia, titania, boria, and zirconia-alumina. These support materials can be used alone or in any combination. In addition to Y zeolite, beta zeolite and other support materials, the present catalyst contains a metallic hydrogenation component. The hydrogenation component is preferably provided as one or more basic metals uniformly distributed in the catalyst particle. The hydrogenation component is one or more elements of groups 6, 9, and 10 of the periodic table. Noble metals such as platinum and palladium can be applied, although
the best results have been obtained with a combination of two base metals. Specifically, nickel or cobalt is used together with tungsten or molybdenum, respectively. The preferred composition of the metallic hydrogenation component is nickel and molybdenum or nickel and tungsten. The amount of nickel or cobalt is preferably 2 to 8% of the weight of the finished catalyst. The amount of tungsten or molybdenum is preferably from 8 to 22% of the weight of the finished catalyst. The total amount of metallic hydrogenation component is from 10 to 30% of the weight of the finished catalyst. The catalyst of the present process can be formulated using conventional techniques in the industry. This can be summarized, with great generalization, as mixing the zeolite beta and zeolite Y with the other inorganic oxide components and a liquid such as water or mild acid to form an extrudable mass, followed by extrusion by a die plate of multiple perforations. The extrudate is collected and preferably calcined at a high temperature to harden the extrudate. The extruded particles are then screened to obtain a uniform size, and the hydrogenation components are added by immersion impregnation, or the well-known incipient humidification technique. If the catalyst contains two metals in the hydrogenation component, these can be added in
sequence or simultaneously. The catalyst particles can be calcined between metal addition steps, and again after the metals have been added. In another embodiment, it may be convenient or preferable to combine the refractory and porous inorganic oxide, the zeolite beta and the zeolite Y, and compounds containing the metals, then grinding the already combined materials, extruding the ground material, and finally calcining the extruded material. . The milling is carried out with a metal source, such as ammonia heptamolybdate or ammonia metatungstate and another source of another metal, such as nickel nitrate or cobalt nitrate, where both source compounds are generally introduced to the combined materials in the form of solution harassing or a salt. Similarly, other metals can be introduced in dissolved aqueous form, or as salt. It is also possible to introduce non-metallic elements, i.e. phosphorus, by incorporating a soluble component such as phosphoric acids into the aqueous solution. Other methods of preparation are described in U.S. Pat. Nos. 5,279,726 and 5,350, 501, which are hereby incorporated by reference in their entirety. The catalysts prepared by the methods discussed above contain the hydrogenation metals in the oxide form. The oxide form is usually converted to sulfide form
hydrodisintegration. This can be achieved by any of the known sulfation techniques, including pre-sulfating ex situ prior to loading the catalyst into the hydrodisintegration reactor, pre-sulfating after loading the catalyst into the hydrodisintegration reactor and before using it at an elevated temperature, and sulfation in situ, that is, using the catalyst in oxidized form to hydrodisintegrate a hydrocarbon feedstock containing sulfur compounds under hydrodisintegration conditions, including elevated temperature and pressure, and the presence of hydrogen. The hydrodisintegration process disclosed herein will be operated within the general range of conditions that are currently used commercially in hydrodisintegration processes. In many instances, the operating conditions are specific to the refinery or processing unit. That is, they are largely dictated by the construction and limitations of the existing hydrodisintegration unit (which normally can not be modified without significant expense), the composition of the food and the desired products. The inlet temperature of the catalyst bed should be from 232 to 454 ° C, and the inlet pressure should be from 5,171 to 24,132 kPa (g), and typically from 6,895 kPa (g) to 24,132 kPa (g). The feed stream is mixed with enough hydrogen to
produce a volumetric flow velocity of hydrogen per unit of feed volume from 168 to 1,684 normal liters / liters measured at 0 ° C, and 101.3 kPa (a) measured at 15.6 ° C and 101.3 kPa (a), and pass to one or more reactors containing fixed beds of catalyst. The hydrogen will be derived primarily from a stream of recycle gas that can pass through purification facilities to remove acid gases, although this is not necessary. The hydrogen-rich gas mixed with the feed and, in one embodiment, any recycle hydrocarbon, will usually contain at least 75 mole percent hydrogen. For hydrodisintegration to produce distillates, the feed rate in terms of VELH will normally be within the broad range of 0.3 to 3.0 hr "1. As used herein, VELH means hourly liquid space velocity, which is defined as the volumetric flow rate of liquid per hour divided by the volume of the catalyst, where the volume of liquid and the volume of catalyst are in the same volumetric units Typical feeding to the process disclosed herein is a mixture of various different hydrocarbons and compounds Co-boiling recovered by fractional distillation of a crude oil will normally contain components with a boiling point higher than the maximum
boiling range of 149 to 371 ° C to produce distillates. Frequently it will have a range of boiling points of more than 340 ° C, and that in one mode it is less than 482 ° C, in another mode it is less than 540 ° C, and in a third mode it is less than 565 ° C. This petroleum derivative feed may be a mixture of streams produced in a refinery, such as atmospheric gas oil, coke gas oil, distillation gas oil, deasphalted gas oil, vacuum gas oil and FCC recycle oil. A typical gas oil comprises components that boil in the range of 166 to 566 ° C. Alternatively, the feed to the process disclosed herein may be a single fraction, such as heavy vacuum gas oil. A typical heavy gas oil fraction has a significant proportion of component hydrocarbons, usually at least 80 percent of the weight, boiling at between 371 and 566 ° C. Mixtures of synthetic hydrocarbons, such as those recovered from tar or coal, can also be processed with the present process. The feed can be subjected to hydrotreatment, or treated by extraction with solvents before passing to the present process to remove large amounts of sulfur, nitrogen or other contaminants such as asphaltenes. It is considered that the present process will convert a large portion of the feed to more volatile hydrocarbons as hydrocarbons in the boiling range of distillates.
Typical conversion ratios vary from 50 to 100 percent of the volume (hereinafter referred to as% -vol), depending largely on the feed composition. The conversion ratio is between 60 and 90% -vol in one modality of the process revealed in the present, from 70 to 90% -vol in another modality, from 80 to 90% -vol in another modality more, and from 65 to 75% -vol in another modality more. The process effluent will contain a wide variety of hydrocarbons, from methane to essentially intact feed hydrocarbons, above the boiling range of any desired product. The process effluent typically passes from a reactor containing a catalyst, and is usually separated by methods known to one of ordinary skill in the art, including phase separation or distillation, to produce a product with any desired final boiling point. Hydrocarbons that boil above the final boiling point of any desired product are designated unconverted products, even if their boiling point has been reduced to some extent in the process. The majority of the unconverted hydrocarbons are recycled to the reaction zone with a small percentage, that is to say, 5% of the weight is removed as a carry-over stream. To produce distillates, at least 30% by weight, and preferably at least 50% by weight, of the effluent bursts at less than 371 ° C.
The process and composition disclosed herein may be used in what is designated in the one-stage or two-stage process flow technique, with or without prior hydrotreating. These terms are used as defined and illustrated in the book entitled Hydrocracking Science and Technology, by J. Scherzer and AJ. Gruia, ISBN 0-8247-9760-4, Marcel Dekker Inc., New York, USA, 1996. In a two-stage process, the present catalyst can be used in the first or second stage. The catalyst may be preceded by a hydrotreating catalyst in a separate reactor, or charged to the same reactor as that of the hydrotreating catalyst, or a different hydrodisintegration catalyst. An upstream hydrotreating catalyst can be used as a feed pre-treatment step, or for hydrotreating unconverted recycled materials. The hydrotreating catalyst can be used for the specific purpose of hydrotreating polynuclear aromatic compounds (APN) to promote their conversion into subsequent hydrodisintegration catalyst beds. The present catalyst can also be used in combination with a different second catalyst, such as a catalyst based on zeolite Y or with mainly amorphous disintegration components. In some embodiments of the process disclosed herein, the catalyst is used with a feed or in
a configuration such that the feed that passes through the catalyst is a raw mixture, or is similar to a raw feed. The sulfur content of crude oil, and therefore the feed to this process, varies greatly, depending on its source. As used herein, "crude stream" refers to a feed that has not been hydrotreated, or that still contains organic sulfur compounds that produce a sulfur level of more than 1,000 parts per million by weight, or that it still contains organic nitrogen compounds that produce a nitrogen level of more than 100 parts per million of the weight (0.01% by weight). In other embodiments of the process disclosed herein, the catalyst is used with a feed that has been hydrotreated. Those skilled in the art of hydrocarbon processing know and can practice the hydrotreating of a crude mixture to produce a hydrotreated feed to be charged to the process disclosed herein. Although the sulfur level of the hydrotreated feed may be from 500 to 1,000 parts per million of the weight, the sulfur level of the hydrotreated stream is less than 500 parts per million of the weight in one embodiment of the process disclosed herein. , and from 5 to 500 parts per million of the peso in another modality. The nitrogen level of the hydrotreated stream is less than 100 parts per
million of the peso in one modality, and of 1 to 100 parts per million of the peso in another modality. All references in the present to the groups of elements of the periodic table are to the "New notation" IUPAC in the periodic table of elements in the fourth linings of the book entitled CRC Handbook of Chemistry and Physics, ISBN 0-8493-0480 -6, CRC Press, Boca Raton, Florida, USA, 80th Edition, 1999-2000. All references in the present to surface area are single point surface areas at a partial pressure nitrogen p / po of 0.03, determined by the BET method (Brunauer-Emmett-Teller), using the nitrogen adsorption technique described in ASTM D4365-95, Standard test method for determining volumes. of micropores and zeolite areas of a catalyst, and in the article by S. Brunauer et al., J. Am. Chem. Soc, 60 (2), 309-319 (1938). All references herein to boiling points are the boiling points determined by ASTM D2887, Standard Test Method for Bore Range Distributions of Petroleum Fraction by Gas Chromatography. ASTM methods are available from ASTM International, 100 Barr Harbor Drive, P.O. Box C700, West Conshohocken, Pennsylvania, USA The following examples are provided for illustrative purposes, and not to limit the process and
composition defined in the claims. EXAMPLE 1 Sample 1 A modified Y zeolite was prepared by steam treatment of a Y zeolite exchanged with ammonia marketed by UOP LLC (Des Plaines, Illinois, USA), and designated in the literature as Y-84, with a content of sodium of less than 0.2% of the weight calculated as Na2Ü. The resulting modified Y zeolite is designated in the present "Sample 1", and had a general mole ratio of silica versus alumina (S1O2 versus A1203) of 5.0 against 5.5, a unit cell size of 24.28 angstroms, and a surface area of 540 to 640 m2 / g. EXAMPLE 2 Two catalysts (A and B) were prepared by mixing in a grinder Sample 1, a beta zeolite with a general molar ratio of silica versus alumina (SIO2 against A1203) of 23.8, and an SF6 adsorption capacity of 29% by weight and containing the template used during its synthesis if present, amorphous silica-alumina, and boehmite C Catapal ™ alumina peptized in HN03. The amorphous silica-alumina was silica-alumina CCIC with a nominal composition of 75% by weight of silica and 25% by weight of alumina. The silica-alumina CCIC is available from Catalysts & Chemicals Industries Co. Ltd. (CCIC). The Table describes the
quantities of these components based on dry weight in each final catalyst. The resulting mixture was extruded into cylindrical particles of 1.6 mm in diameter and 3.2 to 12.7 mm in length. The dried extrudates were dried at 104 ° C for a minimum of 4 hours, and then calcined at temperatures of more than 550 ° C for a minimum of 90 minutes. For catalysts A and B, sufficient nickel nitrate was added to supply 5% by weight of nickel (calculated as Ni) in the final catalyst, and enough ammonia metatungstate to supply 17.5% by weight of tungsten (calculated as W). ) in the final catalyst, to the calcined extrudates until reaching incipient humidity. The extrudates were dried to have free flow, and then oxidized by calcination at 500 ° C for a minimum of 90 minutes. EXAMPLE 3 The two catalysts described above were pre-sulphided by passing a gas stream consisting of 10% -vol of H2S and the balance of H2 through a bed of catalyst at a temperature of initially 149 ° C, which was slowly raised to 413 ° C, which was maintained for 6 hours. The activities and hydrodisintegration selectivities (ie, product yields) of the two catalysts were compared in simulated first stage tests. Specifically, the two were tested separately
catalysts for hydrodisintegrating a hydrotreated vacuum gas oil (VGO) feed, with a specific gravity of 0.877 to 15.6 ° C (API gravity of 30.05 °), an initial boiling point of 107 ° C, a boiling point of 5% of the weight of 195 ° C, a final boiling point of 550 ° C, and a boiling point of 50% of the weight of 24 ° C, with 13% of the weight bulging at less than 288 ° C, and 26% of the weight bubbling at less than 371 ° C. Each catalyst was tested in a simulated first-stage operation by passing the feed load through a laboratory-sized reactor to a VELH of 1.5 hr-1, a total pressure of 13,786 kPa (g), and a volumetric hydrogen feed rate per unit of feed volume of 1,684 ltr normal / ltr measured at 0 ° C and 101.3 kPa (a) (10,000 SCFB measured at 15.6 ° C and 101.3 kPa (a)). Sufficient di-tert-butyl disulfide was added to the feed to supply 2.1% by weight of sulfur, and thereby simulate an atmosphere with hydrogen sulfide, as it exists in commercial first stage hydrodisintegration reactors. In addition, sufficient cyclohexylamine was added to the feed to supply 780 parts per million of the weight of nitrogen, and thereby simulate an ammoniacal atmosphere, such as exists in commercial first stage hydrodisintegration reactors. So that the hydrodisintegration tests
produced distillates, the temperature conditions were adjusted as necessary to maintain a conversion of 65% net weight to materials with a boiling point lower than 371 ° C, during the course of 100 hours. The net conversion is the effluent that boils at less than 371 ° C as a percentage of the feed, minus the percentage of the feed that boils at less than 371 ° C. At the end of the 100 hours, a record was made of the temperature required to maintain the conversion of 65% of the net weight, and the relative activities and selectivities of each catalyst were calculated. These data are summarized in the Table. The selectivity values for each catalyst were total distillates (ie, 149 to 371 ° C), light distillates (ie, 149 to 288 ° C), and heavy distillates (ie, 288 to 371 ° C). The relative activity value for each catalyst was entered as the difference between the temperature required for the catalyst to maintain the conversion of 65% of the net weight and a reference temperature that was equal for the nine catalysts. The lower the relative activity value, the more active the catalyst would be.
TABLE
In the Table, the relative catalyst activity is expressed in terms of reactor temperature above the reference temperature required to obtain a net conversion of 65% by weight of VGO up to the cutoff of total distillates. Catalyst A present more selectivity of total distillates, is more active, and has a significantly higher selectivity of heavy distillates than light distillates, compared to Catalyst B.