MXPA96005189A - Procedure to prepare a hydrotreatment catalyst from a hydrotratination catalyst descend - Google Patents

Abstract

The present invention relates to a process for preparing a catalyst suitable for the hydrotreatment of heavy hydrocarbon supplies, a process consisting of the steps of (i) if it is necessary to remove the carbonaceous and sulphurous deposits of the discarded catalyst by means of subjecting the catalyst Even after heat treatment, (ii) crush the spent catalyst obtained in step (i), (iii) mix the ground material obtained in step (ii) with a binder and. optionally, additives, and (iv) molding the mixture to form a new catalyst, in which the loss in ignition of the mixture for the catalyst composition at any point in steps (ii), (iii), (iv) does not be greater than 70% The method according to the dimension is suitable, among other reasons, it is contemplated to incorporate a microporous additive in the composition of the catalyst. The discarded hydrotreating catalyst that has been used to hydrotreat light hydrocarbon supplies is particularly suitable for use in the process according to the invention.

Description

PROCEDURE FOR PREPARING A HYDROTREATMENT CATALYST fl FROM A DISPOSED HYDROTRATINATION CATALYST In petroleum refining, large-scale catalysts are used in the hydrotreatment of hydrocarbon supplies to remove contaminants, such as metal-containing compounds, sulfur-containing compounds and nitrogen-containing compounds. Apart from the removal of contaminants, the hydrotreatment can also effect the hydrofraction of the supply material to the compounds with a lower boiling point. The catalysts used in these procedures are well known in the art. They generally consist of a metallic hydrogenation component of group VI, for example molybdenum or tungsten, and a metallic hydrogenation component of group VIII, for example cobalt or nickel, on a refactant oxide carrier. The oxide carrier usually consists of alumina, silica, silica-alumina, magnesia, titania or mixtures thereof. The catalyst may also contain other components, such as phosphorus or zeolites. During hydrotreatment of hydrocarbon supplies, the activity of the catalyst decreases. This is the cause, among others, of the accumulation on the surface of the catalyst of carbonaceous and sulphurous deposits. In addition, if the catalyst is used to hydrolyse supply materials containing metals, contaminating metals, such as vanadium and nickel, will accumulate on the surface of the catalyst in the form of its sulfides. The accumulation of carbonaceous, sulphurous and metallic deposits is detrimental to the activity and selectivity of the catalyst. When these processes continue for a long time, the catalyst yield decreases to an unacceptably low level and the catalyst must be replaced. The spent hydrotreating catalyst obtained in this way must then be discarded. One way to dispose of the spent hydrotreating catalyst is through the landfill, but this is becoming increasingly difficult due to environmental restrictions. The catalysts used for the hydrotreatment of hydrocarbon supplies containing metals, and therefore contain contaminating metals such as vanadium and nickel, in addition to the hydrogenation metals, can be sold to a metal recovery, who will recover not only the metals of hydrogenation but also polluting metals. Obviously, metal recuperators are mainly interested in spent catalysts that contain considerable amounts of polluting metals and much less interested in the catalysts that have been used for the hydrotreatment of lighter supply materials and therefore do not contain or contain only polluting metals. This means that it is even more difficult to discard spent hydrotreating catalysts, used to treat water between lighter supply materials, than the hydrotreating catalysts used to hydraulically use heavy metal containing materials. In any case, both the landfill and the recovery of metals are expensive. Therefore, there is a need for a process for the disposal of spent hydrotreating catalysts, especially the spent hydrotreating catalysts that have been used to hydraulically treat lighter hydrocarbon feeds. Another problem that is increasingly found in the field of oil refining is that the supply materials to be refined tend to become increasingly heavy. Heavy supply materials, such as supplies based on atmospheric waste oils, vacuum waste oils, tar sand oils, and shale oils, contain substantial amounts of sulfur and hydrogen components, metal components and high molecular weight components such as asphaltenes. These impurities, and particularly the presence of high molecular weight metal components, result in a relatively rapid deactivation of the catalyst used in the hydrotreating of these heavy supplies compared to the deactivation rates for catalysts used in hydrotreating lighter supply materials. . Therefore, catalysts are used for heavy duty hydrotreatment in large quantities in oil refining, which makes their price an important factor. Accordingly, there is an urgent need for a process for the production of heavy-duty, low-cost hydrotreating catalysts of high quality, and in particular of a process for producing such catalysts based on inexpensive starting materials. Japanese patent publication BBB90 / 1977 discloses a process in which a spent hydrotreating catalyst is calcined to remove carbonaceous and sulphurous deposits, crushed, mixed with a binder and reformulated to form a new hydrotreating catalyst. The essence of the process described in this publication is that the spent catalyst is treated with an aqueous acid or alkaline reaction solution. This treatment is considered necessary to dissolve the hydrogenation metals and to disperse them uniformly through the catalyst. In addition, it is exposed that polluting metals have to be eliminated. As is clear from the examples in this document, the amount of water used in treating the catalyst is very large, with the weight ratio of the water to the spent catalyst being of the order of 5.5: 1. However, the use of such large amounts of water, as considered in the Japanese patent publication, is difficult to handle on an industrial scale. It creates a separate liquid phase, which is undesirable from the technical point of view and because it tends to result in high energy consumption and large amounts of waste. In addition, experiments carried out by the applicant have shown that the use of such amounts of water or acid or alkaline reaction solutions will result in a substantial portion of the hydrogenation metals being leached from the catalyst composition. Needless to say, this is objectionable. Surprisingly, it has now been found that, contrary to the statements of the aforementioned Japanese patent publication, it is not necessary to use large amounts of water or aqueous acid or alkaline reaction solution to produce a newly formulated hydrotreating catalyst, with good properties to from a spent hydrotreatment catalyst. It will be apparent to a person skilled in the art that the ability to dispense with the use of large quantities of water has advantages from the point of view of processing technique, because the presence of a separate liquid stage is avoided. It has also been found that, in accordance with the Japanese patent publication, while it is necessary to redistribute the hydrogenation metals and remove the contaminating metals from the spent catalyst by way of a treatment with water or aqueous solutions, thus causing the undesirable leaching of the metals of hydrogenation, a new high-quality hydro-treatment catalyst can be prepared from a gas + ado hydrotreating ca + alizer containing a large amount of nickel and vanadium, namely up to 15% + by weight, calculated as oxides, based on the weight of spent catalyst from which carbonaceous and sulphurous deposits have been removed, without such treatment being necessary. Although the process of the invention is particularly suitable for the repeated use of a spent catalyst, i.e., a catalyst that has been deactivated by its use in hydrotreating, is also useful in the case of a catalyst that has not been used before for any reason, or for a used catalyst still profitable after its normal regeneration. Apart from hydrotreating catalysts which generally do not consist of a specific fractionation component, hydrotreating catalysts (soft), which do consist of a fractionating component, such as silica, can be used in the process of the invention. - amorphous alumina and? n molecular sieve component, depending on the use considered for the newly formulated catalyst. Again, this type of catalyst can be used, either in the spent form after it has been used in the hydrotreating operations (soft), or in its unspent form. In this description, all possible sources of catalyst suitable for use in the process of this invention will be referred to hereinafter as "waste catalyst".

The present invention then relates to a process for preparing a catalyst suitable for the hydrotreatment of heavy hydrocarbon supplies, a process consisting of the steps of: (i) if it is necessary to remove the carbonaceous or sulphurous deposits of the waste catalyst by means of subjecting the spent catalyst to a heat treatment, (ii) grinding the spent catalyst obtained in step (i), (iii) mixing the ground material obtained in step (ii) with a binder and, optionally, with additives, and ( iv) molding the mixture to form a new catalyst, in which the ignition loss of the mixture of the catalyst composition at any point in steps (ii), (iii) and (iv) is not greater than 70 %. In this context, the loss on ignition represents the loss in weight of the product when it has been heated to a temperature of 600 ° C for one hour. The ignition loss of a product is equivalent to the water content of that product if it does not consist of any other volatile components. Since the components present in steps (ii) to (iv) do not consist of volatile components other than water, a limitation of the ignition loss of the mixture in steps (ii) to (iv) of the process is in effect a limitation of the amount of water present in the mixture. As stated above, the ignition loss of the catalyst composition mixture should not be greater than 70% at any point in steps (ii) to (iv) of the process for the preparation of the catalyst according to the invention . Preferably, the ignition loss should not be greater than 60%, more preferably not greater than 5%. In comparison, during the grinding process of Example 1 of the Japanese patent publication, the ratio of the spent catalyst to the amount of water present is 1: 5.1. This is equivalent to a loss to the invention of 85%. The first step in the process according to the invention is the thermal treatment of the spent hydrotreating catalyst in order to remove the carbonaceous and suds deposits and other compounds. In general, such heat treatment is carried out by heating the spent catalyst at a temperature of between 300 ° and 600 ° C, preferably between 400 and 505 ° C, for a period of 0.1 to 48 hours, preferably between 0.5 and 48 hours. 12 hours. Heating is carried out in an atmosphere containing oxygen.

In this respect it is noted that the sulfur that is present on the spent catalyst is derived from two sources. On the one hand, the spent catalyst contains true sulphide deposits, which were deposited in the catalyst during its previous use. On the other hand, the catalyst also contains sulfur in the sulphide form of the hydrogenation metals, which results from the sulfurization step to which the catalyst is subjected to activate it.

During the heat treatment in the process according to the invention, the true sulphide deposits of the catalyst are removed, while the metal sulphides are converted to metal oxides. In the context of the present specification it is meant that the removal of sulfur deposits by heat treatment includes these two processes.

It should be noted that if the spent catalyst, or more generally the used catalyst, is used in the process according to the invention, it is essential that the spent catalyst be subjected to said heat treatment to remove the carbonaceous and sulphurous deposits before continue to be elaborated. This is for the following reasons. The spent catalyst may contain up to 25% by weight of carbonaceous deposits, calculated as carbon on the weight of the total spent catalyst, and will also contain a substantial amount of sulfur. If the removal of carbonaceous and sulphate deposits is carried out after the spent catalyst has been crushed and molded, the presence of carbon and sulfur would detrimentally affect the binding properties of the binder, resulting in a newly formulated catalyst of insufficient strength. In addition, the carbon and sulfur content of the associated catalyst varies from one source to another. If one were to start from a material from which carbonaceous and sulfur deposits have not been removed, these inhomogeneous characteristics in the starting material would be reflected in a final product of inhomogeneous quality. In addition, the crushing of a catalyst containing carbonaceous and sulphurous deposits is a risky operation, because the catalyst containing these materials is pyrophoric (self-heating).

Obviously, thermal treatment can be dispensed with if a worn-out catalyst is used that contains carbonaceous or sulphurous deposits.

In the next step, the catalyst, which may be either a spent hydrotreating catalyst that has been subjected to a heat treatment as described above, or a new catalyst, is ground, and the fraction with a particle size is isolated. less than 200 microns, preferably less than 50 microns, more preferably less than 20 microns, for example by appropriate screening techniques. The grinding may take place, for example, in a conventional forging workshop.

The crushed catalyst is then compounded with a binder and, if desired, with an additive. The binder is present to adhere the various components of the catalyst. The additive, which may optionally be present, may function as a low-cost filler and as a diluent for the metal content of the discarded catalyst particles, and may also be used to modify the properties of the catalyst to be produced, for example. its density and distribution of pore sizes. The additive can also add catalyst-specific properties to the catalyst, such as hydrofraction activity or metal-capturing activity. It is of course impossible to make a clear distinction between the binders and the additives, since the compound added as an additive may also have some binding properties, while an aggregate compound as a binder, may also function as a diluent and may provide the catalyst with additional properties. . Examples of suitable binders are alumina, silica-alumina and titania. In general, alumina is the preferred binder because it has good binding properties and can easily be kneaded. Their use usually results in catalysts with satisfactory properties in terms of, for example, strength.

Examples of suitable additives are silica-alumina, diatomaceous earth, sepeolite and natural or synthetic clays, such as kaolin or kaolin leached by acid. If desired, a spent or new catalyst from the Federal Communications Commission can be incorporated, optionally after being crushed, into the catalyst to be prepared by the process according to the invention. Amounts up to 30% by weight, calculated on the new catalyst, are contemplated. The addition of the catalyst from the Federal Communications Commission can have a positive effect on the strength of the catalyst to be produced, as well as on the conversion of the high-boiling supply materials to the resulting catalyst.

The amount of spent catalyst, binder and additive will vary with the use of the intended catalyst. This will be illustrated more fully below.

The mixture consisting of the crushed catalyst, the binder and, optionally, the additives is formed into particles. This is done by methods known in the art, such as extrusion, granulation, beading, tablet compression, pill making, briquette, etc. The size of the particles will depend on the contemplated use for the newly formulated catalyst. The shape of the particles of the newly formulated catalyst is variable. Some suitable shapes are cylinders, beads, rings, and symmetric and asymmetric polylobes, such as trilobes and quadrilobes. Cylinders are sometimes preferred for reasons of strength.

After the molding step, the resultant particles of the catalyst are generally subjected to a drying step followed by a calcination step. The drying step can be carried out at a temperature of 40 ° to 150 ° C, preferably 100 ° to 130 ° C, for a period of 0.5 to 48 hours. It will usually be carried out in a calcination step at a temperature on the scale of 350 ° to 600 ° C for a period of 0.5 to 48 hours in an oxidizing atmosphere. As stated above, the present invention is based on the fact that? n treatment with a large amount of water or aqueous solution of acid or alkaline reaction is not only necessary when preparing a newly formulated hydrotreating catalyst with good properties, but in fact it goes accompanied by undesirable results. Accordingly, the process according to the invention has the amount of water limited by limiting the loss to the invention of the preparation mixture for the catalyst during the steps of grinding, reformulating and tumbling at a value not exceeding 70% However, this does not mean that the process according to the invention is carried out in the complete absence of water or aqueous solutions of acid or alkaline reaction. First, the compounds to be added to the catalyst composition contain some internal water, which is manifested by the ignition loss that occurs. In addition, a limited amount of water or aqueous solution of acid or alkaline reaction will generally be added to the catalyst composition during the various steps of the process of grinding, mixing with other components and molding. For example, the addition of water during the grinding step may be desirable to facilitate grinding. During the mixing step it may be desirable to add one of the components in the form of an aqueous solution or dispersion, or it may be desirable to add some water to mix rnas easily. During the molding step, a little water can be added to facilitate molding or an aqueous acid reaction solution can be added to peptise an alumina binder, if present. However, in any case the ignition loss of the mixture for the preparation of the catalyst present in steps (ii), (iii) and (iv) of the process according to the invention would be less than 70%. As stated above, the presence of less water or aqueous solution results in better advantages from the point of view of processing technology and in the case of aqueous solutions of acid or alkaline reaction which are also used at a lower risk of the hydrogenation metals. In general, all types of spent and discarded hydrotreating catalysts can be used as the starting material according to the invention. A type of catalyst which is suitable for use in the process according to the invention takes the form of catalysts which can be used or, as the case may be, is suitable for use, in the hydrotreatment of light hydrocarbon charges. These catalysts generally have a content of group VI hydrogenation metals in the range of 10-35% by weight, preferably 17-35% by weight, calculated as trioxide, and a hydrogen content of group VIII. of 1-10% by weight, preferably 2.6% by weight, calculated as oxide. The hydrogenated metal component of group VI is usually molybdenum or vol The hydrogenation metal component of group VIII is usually nickel or cobalt. The catalyst may optionally consist of phosphorus, which is usually present in the amount of 0-10% by weight, calculated as P 2 Os. The catalyst carrier is usually alumina consisting of a minor amount of silica, ie, up to 20% by weight. These catalysts have an average diameter of boron on the scale of 4-15 n, preferably 6-10 nm. In the present specification, the term "average pore diameter" is defined as the diameter at which half the volume of the pores is in the pores with the smaller diameter of said diameter and half the volume of the pores is present in the pore. the pores with larger diameter of said diameter. The pore volume is defined as the volume of pores determined by the introduction of mercury present in the pores with diameter less than 100 nrn. The use of these types of catalysts in the process according to the invention is particularly attractive for two reasons. First, as explained above, it is difficult to discard these types of catalysts by sanitary landfill or metal recovery. Second, the catalysts that have been used for the retreatment of light hydrocarbon feeds are relatively clean insofar as they hardly contain contaminating metals, for example, they contain less than 5% by weight of polluting metals, calculated as oxide upon the catalyst from which the sulphurous and carbonaceous deposits have been removed, preferably less than 3% by weight, most preferably even less than 1% by weight. Another, although less preferred, source of discarded catalyst for use in the process of the invention consists of catalysts that have been used, or area of payment for their use, in the retreatment of resins. The resin catalysts have a mean pore diameter of the order of 6-25 nm and a relatively low hydrogenation metal content, the hydrogenation metal being generally present in group VI in an amount of less than 17% by weight for molybdenum, calculated as trioxide, and the hydrogenation metal of group VIII is generally present in an amount of less than 6% by weight, calculated as oxide. Yet another source of waste catalyst suitable for use in the process according to the invention is a catalyst which has been used for the pretreatment in the presence of hydrogen of fillers which have been supplied to processes of fluidized catalytic operation. These catalysts generally have a group VI hydrogenation metal content of 10-30% by weight, calculated as trioxide, and a group VIII hydrogenation metal content of 1-6% by weight, and an average diameter of pores in the 7-13x nm scale. The outer surface of the particles of these spent catalysts for pretreatment of the Federal Commission is highly contaminated with vanadium, but, as is clear from the analysis of the cross-section of the catalyst particles, the contamination is mainly present on the outer edge of the catalyst particles, the inner part of the catalyst particle having little or no pollution. Accordingly, when this type of spent catalyst is subjected to a temperature treatment to remove the carbonaceous and sulphurous deposits, and subsequently is ground, a particulate material is obtained most of which is hardly contaminated, while only a small part is obtained. It is excessively contaminated. By incorporating the aforementioned particulate particulate material into a catalyst newly formulated with the process according to the invention, it becomes possible to benefit from a non-contaminated catalyst particle. As will be apparent to the skilled artisan, mixtures of various types of spent or discarded catalyst materials can of course also be used. It is noted that the composition of the catalysts given above is based on the catalyst as it was in its unused state, the hydrogenation metal term is used to indicate the metals that were incorporated into the catalyst composition on purpose during the preparation of the catalyst . The metals that are deposited in the catalyst composition during its use are mentioned as polluting metals. Since the amount of contaminating metals present in the catalyst composition depends on a specific process in which the catalyst has been used, it is difficult to give figures for the amount of contaminating metals present in the spent catalyst in general. As indicated above, the spent catalyst containing up to a total of 15% by weight of the contaminating metals, calculated as oxide based on the spent catalyst from which carbonaceous and sulphurous deposits have been removed, are suitable for use in the process according to the invention. Nevertheless, in the process according to the invention, it is preferred to use spent catalyst containing less contaminating metals, either because it has not been used, or because it has been used as a hydrotreatment of charges which contain few or no contaminating metals. Preferably, the discarded catalyst contains no more than 5% by weight, most preferably no more than 3% by weight, most preferably not even more than 1% by weight of the contaminating metals, calculated on the catalyst from which the deposits have been removed. carbonaceous and sulfurous (clean catalyst). If desired, other hydrogenation metals can be added to the catalyst composition, for example, by impregnating the newly formulated catalyst with an impregnation solution containing water-soluble salts of the hydrogenation metals to be incorporated into the composition. of the catalyst. Other compounds of which the addition of the newly formulated catalyst, such as phosphorus, may be desired for incorporation into the new composition may also be incorporated into the catalyst composition by impregnation, either in combination with additional or separate metals. When the newly formulated catalyst is impregnated as such, a considerable amount of the hydrogenation metals is absorbed by the crushed particles of the discarded catalyst. If this is objectionable, it is possible to contact the additive with the hydrogenation or phosphorus metals before being mixed with the crushed particles of the disposable catalyst. For reasons of good order it is noted that other metals are added to the catalyst composition, care must be taken once again to ensure that the addition of the mixture for the preparation of the catalyst does not exceed 70% during the optional addition of other metals or other components. . The term "catalyst suitable for the hydrotreatment of heavy feed material" refers to a catalyst which can carry out one or more of the following processes on a heavy hydrocarbon feedstock over a reasonable period: hydrodesulphurisation, hydrodesitrogenation, hydrodemetalization, and Hydro-cracking. By the expression of the reasonable period is meant a period that an expert will consider acceptable on a commercial time scale. The catalyst prepared by the process according to the invention is suitable for the hydrotreatment of heavy feed materials. Some examples of heavy materials that can be subjected to hydrotreatment with the catalyst prepared by said process are the materials that contain atmospheric reeiduae, residues in the vacuum, residues mixed with oils for gas, particularly oils for gas in vacuum, crude oil, shale oils and tar sand oils. Generally, the boiling scale of such heavy feed materials is such that at least 70% of the volume will boil at more than 450 ° C. The initial boiling point will usually be 300 ° C, often 350 ° C. The sulfur content of the filler will generally be 1% by weight will often be more than 3% by weight. The nitrogen content is generally greater than 500 ppm and will often be in the range of 500 to 4000 ppm. The supply material contains contaminating materials such as vanadium, nickel and iron, generally in amounts greater than 3 ppm, frequently in the range of 30 to 100 ppm, and more frequently in the range of 50-300 ppm, calculated as metal. Two types of methods can be recognized for the hydrotreatment of heavy materials supplied in the art, namely the fixed bed processes and the moving bed processes. In the fixed-bed process, the supply is conducted through a fixed bed of the catalyst under conditions of increased temperature and pressure. Typical conditions for hydrotreating the fixed bed include temperatures between 300 and 450 ° C, hydrogen pressures between 25 and 200 bar, oil hydrogen ratios between 300 and 2000 NI / I and space velocities (hr-i) between 0.1 and 3. In the hydrotreatment of heavy supplies a system is commonly used to catalyst grade. This means that the supply is first contacted with a suitable catalyst to remove the metal components from the supply materials. The effluent stream of the first catalyst bed, after optional fractionation and phase separation, is supplied to a second catalyst bed, optionally followed by subsequent beds. The second and subsequent catalyst beds are for conducting hydrodesulfurization, hydronitrogenation, and / or Conradson carbon removal. A catalyst grade system generally consists of two to five catalyst beds. Fixed-bed processes for the hydrotreatment of heavy cargoes of some are known in the art and do not require further elucidation here. As the name indicates, the essence of the moving bed process is that the catalyst particles move with respect to the reactor and that they are contained, with the result that the catalyst particles and the. supply are mixed perfectly. An example of a fixed bed process is an extended fixed bed process, also known as a bored bed process. In a typical boiling bed process, HRI hydrogen-oil process, the supply and the hydrogen-containing gas with which the supply is to be treated are introduced into the lower part of a reactor containing a boiling bed catalyst. . The spent catalyst is removed from the bottom of the reactor at regular intervals, while the new catalyst is added to the top. This eliminates the need to close the factory by replacing the catalyst. In the extended moving bed, an intimate contact is made between the catalyst particles, the supply and the hydrogen by means of internal circulation. The mobile bed technology has the advantage of being very flexible with respect to the nature of the proposed supply materials. Some suitable supply materials are, for example, vacuum residues, atmospheric residues and heavy raw materials. The product will be, for example, gasoline, light oil for gas, vacuum oil for gas and atmospheric oil for gas. An advantage of a moving bed process over a fixed bed process is the constant quality of the fluid product, because, unlike a fixed bed process, it is deactivation of the catalyst as a function of time. Various types of moving bed processes are known in the art, including bored bed processes. Mention may be made of the aforementioned hydrogen-oil process and the procedure "refining LC of Lu rnus. It is generally carried out the procedures d movable bed at a temperature of 400 ° and 500 ° C, a pressure between 100 and 200 bars, a ratio H2 / oil between 700 and 1400 NI / I. The rate of catalyst addition is usually in the range of 0.3-3 kilograms of catalyst per cubic meter of supply. It should be noted that the specific values for all these parameters, and in particular for catalyst consumption, depend very much on the supply nature, the nature of the catalyst and the other conditions of the process. The nature of the process by which the heavy supply will be hydrotreated influences the properties of the catalyst or the catalysts to be used therein. For example, the properties of a fixed bed catalyst suitable for the hydrotreatment of heavy supply materials will depend on whether it is to be used in a graded bed catalyst system., and if so, if it is to be used in the early or later stages of such a system. In a graded bed system, the supply material is first contacted with a catalyst having a high average pore diameter and a low metal content, a catalyst which is particularly suitable for hydrodesizing. The catalyst or subsequent catalysts have consecutively lower average pore diameters and consecutively higher metal contents, to make them consecutively more suitable for hydrodesulfurization and hydrodesnitrogenation. Due to the nature of the process, the reaction of the mobile bed reactors is impossible. Therefore, the properties of the moving bed catalyst should be selected so that each catalyst particle can develop all the reactions that need to be carried out. The properties of moving bed catalysts and fixed bed catalysts suitable for the hydrotreatment of heavy supply materials will be discussed in more detail below. In order to be suitable for use in the hydrotreatment of heavy supply materials, the catalyst prepared for a process according to the invention should have a particle diameter over the smallest cross section of 4 mm or less, preferably 2 mm. or less, most preferably still between 0.5 and 1.5 mm. For fixed-bed catalysts the diameter of the particles on the smallest transverse reaction is preferably 0.1-1.5 min, for the catalysts of the moving bed the diameter of the particles on their smaller transverse section is preferably 0.8-1.3 nm. The catalyst suitable for the hydrotreatment of heavy supply materials prepared for the process according to the invention usually consists of a Group VI metal in an amount of 0.01-0.12 moles per 100 grams of the catalyst, and / or a metal of the Group VIII in an amount of 0.004-0.08 moles per 100 grams of catalyst. Preferably, the catalyst consists of molybdenum and / or tungsten as a metal component of group VI of nickel and / or as a metal component of group VIII. An amount of 0.01-0.12 moles of molybdenum can be recalculated per 100 grams of catalyst at 1.5-17% by weight of molybdenum, calculated as trioxide on the weight of the catalyst. For the tungsten, an amount of 0.01-0.12 moles per 100 grams of catalyst corresponding to 2.3-27% by weight of tungsten, calculated as trioxide, can be calculated on the weight of the catalyst. For the metals of group VIII nickel and cobalt, the amount of 0.004-0.08 moles per 100 grams of catalyst can be calculated corresponding to an amount of 0.3-6% by weight, calculated as catalyst oxide. A fixed-bed catalyst to be used in the early stages of a heavy-duty hydrotreating operation, which is to perform primarily hydrodemetalization, preferably has a group VI metal content of 0.01-0.09 moles per 100 grams of catalyst and a group VIII metal content of 0.004-0.05 moles per 100 grams of catalyst. For a catalyst consisting of molybdenum and nickel, it would produce a catalyst consisting of 1.5-13% by weight of molybdenum, calculated as trioxide on the catalyst, and 0.3-4% by weight of nickel, calculated as oxide on the catalyst. catalyst. A fixed-bed catalyst to be used in the last stages of a heavy-duty hydrotreating operation, which has to carry out the hydrosulfurization and / or the hydrodehydrogenation, preferably has a Group VI metal content of 0.06-0.12 moles. per 100 gram of catalyst and a content of metals. Group VIII of 0.02-0.08 moles per 100 grams of catalyst. For a catalyst that consists of molybdenum and nickel, this would produce a catalyst that consists of 8-17% in molybdenum, calculated as trioxide on the catalyst, and 1.5-6% by weight of nickel, calculated as oxide on the catalyst. A mobile bed catalyst to be used in a hydrotreating operation with heavy supply, which has to carry out the hydrodesmetalization as well as the hydrosulfurization and / or the hydrodesnitrogenation, preferably has a group VI metal content of 0.035-0.12. moles per 100 grams of catalyst and a group VIII metal content of 0.013-0.08 moles per 100 grams of catalyst. For a catalyst consisting of molybdenum and nickel, it would produce a catalyst consisting of 5-17% by weight of molybdenum, calculated as trioxide on the catalyst, and 1-6% by weight of nickel, calculated as oxide on the catalyst.

It may be attractive to incorporate a phosphorus component in the catalyst composition, especially if the catalyst is to effect hydrodesitrogenization of heavy hydrocarbon supply materials. If phosphorus is incorporated into the catalyst composition, it is preferably present in an amount of 0-0.14 moles per 100 grams of the catalyst, which is equivalent to 0-10% by weight of phosphorus, calculated as P2O5, on the catalyst. Fixed-bed catalysts suitable for the hydrotreatment of heavy supplies prepared for the process according to the invention generally have a pore volume of 0.4-1.5 ml / g, and an average pore diameter of 6-25 nm as determined by mercury symmetry. The fixed-bed catalysts to be used in the same subsequent steps of the hydrotreating operation preferably have a pore volume of 0.5-1.5 ml / g and a mean pore diameter of 12-25 nm. Fixed-bed catalysts to be used in the later stages of the hydrotreating operation preferably have a pore volume of 0.4-0.8 ml / g and an average pore diameter of 6-15 nm. The mobile bed catalysts, and particularly the boiling bed catalysts, can be divided into two groups, namely the monomodal catalysts, which have a mean pore diameter of the scale of .1-15-15 nrn, and the baryed catalyst, which they have an average pore diameter of 4-12 nm, preferably 6-9 nm, and furthermore have a substantial amount of pore volume present in the range of macropores, ie pores with diameter greater than 100 nm. Preferably, a bimodal moving bed catalyst prepared for the process according to the invention has a total pore volume of? .5 to 1.0 ml / g, preferably 0.6-1.0 ml / g, the volume of macropores being 0.05- 0.3 ml / g, preferably 0.1-025 ml / g. Speaking in general terms, it is contemplated to prepare catalysts suitable for use in the moving-bed or fixed-bed process with the process according to the invention comprising 5-95% by weight of the spent catalyst and 95-5% by weight of the other components. The process according to the invention is particularly suitable for the preparation of mobile bed catalysts from discarded hydrotreating catalysts. It is intended as a permanent bed catalyst perrnanesca in a unit for a prolonged period, for example 4 months to 2 years. If the catalyst has to be replenished before scheduled, this is costly for the refinery for the additional time that the rector is out of service. On the other hand, in a moving bed process the catalyst is continuously replenished. Therefore the quality of the product is more important for fixed bed catalysts than for mobile bed catalysts. This means that the sales weight of a mobile bed catalyst suitable for the hydrotreatment of heavy supply materials is even more critical than the sales weight for a fixed bed catalyst suitable for the hydrotreatment of heavy supply materials. Therefore, it is especially attractive to prepare mobile bed catalytic converter from inexpensive starting material conti- nuted by the spent or discarded hydrotreating catalyst. An interesting embodiment of the present invention is the preparation of a dimodal bored bed catalyst using 20-80% by weight of waste hydrotreatment catalyst. 5-30% by weight of binder and 5-50% by weight of microporous additive. As explained above, several hydrotreating catalysts have an average pore diameter on the same scale as the average pore diameter of the esopho of a dimedal bored bed catalyst. However, it does not usually have a volume of macropores required for a bored bed catalyst. Eeta efficiency is remedied by the addition of a macroporous additive, co or diatumasia earth, sepiolita and arsilla natural and synthetic, such as caolina, and caolina * lecciviada acid. Apart from adding volume of macropros, the microporous additive can be used as a diluent for the metals present in the starting material in the hydrotreating catalyst, contracted from metals, which is generally higher than the desired metal content. the boiling bed catalyst to be prepared. Addition of a macroporous additive to the composition of the freshly formulated catalyst placed it at a reduced bulk density, making the catalyst suitable for use in the bored-bed process. The discarded hydrotreating catalyst which has been used as the case may be, has been adduced for use in hydrosulfurization with the hydrodesnitrogenation of the light hydrocarbon supplies, it is a starting material particularly suitable for this mode. As explained above these catalysts have a Group VI metal component of 10-35% by weight and a Group VIII metal content of 1-10% by weight, particularly 2-6% by weight with an average diameter of pores 4-15 nm, more particularly 6-10. Depending on the intended use of the newly formed catalyst it may be desirable to undergo the catalyst before it is used ie it makes the metal components present therein sour. This can be done in a conventional manner, for example, by contacting the catalyst which is in the reactor at an increasing temperature with a hydrogen and a supply containing asufre, which is optionally fixed with a sulfur compound such as DriDS, or with a mixture of hydrogen and hydrogen sulfide, or by means of presulfurizing part after activation. Presultration is generally desirable when the catalyst is to be used in a fixed-bed process, while as a general rule presulphurization is not carried out when the catalyst is to be used in a moving-bed process, more particularly, a bored bed procedure.

Example 1 This example illustrates the limited effectiveness of hydrotreatment described in the Japanese report No. 68890/1977. A spent hydrotreating catalyst consisting of molybdenum and cobalt as hydrogenation and banadium and ñique metals as polluting metals was subjected to a heat treatment for 10 hours at a temperature of 525 ° C in the air to remove carbuncle and eulfuroeoe spares. The heat treated catalyst was ground to a particle size of less than 200 mμ. The crushed catalyst is described with 50 grams of alumina binder per 100 grams of spent catalyst. Then the mixture was given by instruction to form cylindrical extrudates with a diameter of 1.0 nm. The extrudates were calcined for 2 hours at a temperature of 450 ° C in the air. 20 grams of each type of calcined extrudate were subjected to the solution treatment described in Examples 1 to 5 of the Japanese publication followed by the calcination step described in the publication. The metal content of each newly formed catalyst was determined after the final step of calcination. The treatment conditions are given, the final temperature of clacking the metal content in table 1.

Table 1 It can be seen from table 1 that compared to sample 1, not all treatments, whether treated with water or with an aqueous solution of acid or alkaline reaction, lead to a reduction in the content of the hydrogenation metals molybdenum and cobalt and of the metal contaminant nickel. The reduced content of molybdenum is more pronounced when formic acid or ammonia is used. The reduced content of cobalt is very pronounced when formic acid or hydrochloric acid is used, while the use of water is also considered to be a reduction of the cobalt content of almost 50%. Only the use of formic acid has a specific influence on the vanadium content of the catalyst. The results can draw the following conclusions. Treatment with water or an acidic or alkaline reaction solution which is considered essential according to the Japanese Patent Publication * effectively results in the removal of the contaminating nickel, but only at the expense of the contaminating removal of the desirable hydrogenation metals. The elimination of vanadium does not take place in abeoluto. Example 2 This example describes the production of a boulder-bed catalyst with the process according to the invention. The starting material was a discarded hydrosulfurization catalyst consisting of dispersion by weight of carbonaceous deposits, calculated as carbon, and 10.3% by weight of asufre, calculated as asufre. This was removed from the catalyst by subjecting it to a heat treatment at a temperature of 525 ° C for a period of 10 hours in an atmosphere containing oxygen. The spent or clean catalyst obtained in this way consisted of 20% by weight of molybdenum, calculated as thioxide, 5% by weight of cobalt, calculated as oxide, 0.2% by weight of vanadium, calculated as oxide, and 0.1% by weight of nickel, calculated as oxide, all based on the weight of clean spent catalyst. 2970 grams of clean spent catalyst (LOI 12.4%) were mixed with .1,410 grams of alumina (LOI 25.7%) and 393 grams of diatornaceous earth (LOI 8.4%). To the mixture thus obtained were added 24 grams of nitric acid to 54% by weight dissolved in 1500 grams of water, after which the resulting mixture was kneaded. After 12 minutes, 250 grams of water were added and the mixture was mixed again. This action was repeated several times until the mixture was * extrudable. At this point the loss to the invention of the mixtures remains 45%. The mixture was extruded when obtained using a Uelding extruder at a pressure of 40 bar to form strings with a diameter of 1 mm. The extrudates were dried overnight at a temperature of 120 ° C and subsequently calcined for 1 hour at a temperature of 600 ° C in the air. The last catalyst contains 13% by weight of molybdenum, calculated as trioxide, 3.0% by weight of cobalt, calculated as oxide, 10% by weight of earth diato asia, and the lump of counterweight. It had a compact density of 0.58 gram / l, and a PV (H2O) of 0.71 rnl / g.

Example 3 To further illustrate the present invention, various other blasted-bed catalysts were prepared in the same manner as described in Example 2, except that the diatomaceous earth was replaced by different amounts of sepiolite, a catalyst from the Federal Communications Commission, kaolin and bauxite, to obtain catalysts containing 13% by weight of molybdenum, calculated as trioxide, and 3.0% by weight of cobalt, calculated as oxide, 10% by weight of specified additive, and a counterbalanced alumina. PV (H2?) Of several catalysts is given in the following table.

Example 4 The activity of the catalyst according to the invention prepared in Example 2, hereinafter referred to as catalyst A, was determined in comparison with a commercially available bleached bed catalyst containing 13% by weight of molybdenum, calculated as trioxide, and 3.2% by weight of cobalt, calculated as oxide. The catalyst-has a CBD of 0.58 g / ml and a PV (H2?) Of 0.73 rnl / g. This commercial catalyst is hereinafter referred to as comparative catalyst B. The test was run with a tubular rector upstream, probing the two catalysts side by side. Two reaction tubes were filled with 75 nmol of catalyst intermixed homogeneously with 80 i of carborundum particles. After the catalysts had been presulphized using an SRGO in which a dissolved dimethyl sulfide having a sulfur content of 2.5% by weight had been dissolved, oil was passed to Kuwai gas in the preheated vacuum on the catalyst per period of n day Then an atmospheric residue from Kuwait was passed with the properties given in Table 2 on the catalyst for a period of 8 days, according to the test conditions given in Table 3. In Table 2, the amount of asfltenes ( IP-143) represents the fraction of the weight of the supply that is insoluble in n-heptane. The other parameters are known to the person skilled in the art.

Table 2: Properties of the atmospheric waste of the Kuwait.

Table 3; Conditions of the test.

Pictures of the page 22. When the system had reached a state of equilibrium, the activities of the 2 catalysts were compared. The results are given in Table 4, expressed as the relative weight activity of the catalyst A for the different supply components compared to the comparative catalyst B. The determination of relative weight activities was carried out as follows.

Constant of the reaction ratio in the relative weight activity: The constant of the reaction ratio (kHDN) was calculated for each catalyst based on the nitrogen content obtained from the product in cooperation with the nitrogen content of the material supplied. The constant of the reaction ratio for the comparative catalyst B was evaluated at 100, and the constant of the reaction ratio of the catalyst A according to the invention was recalculated to give the desired value of the reaction constant of the reaction in relative weight activity. The relative weight activities for sulfur, metals and carbon of Conradson were calculated analogously, respectively, to the amounts of sulfur, metals and carbon of Conradson present in the supply and the product. Conversion of the relative weight activity: The conversion to the products having a boiling point below 537 ° C was determined for both catalysts, taking into account the portion of the supply material which was already boiling on this scale. From these conversions two relationship constants were calculated, one for catalyst A, the other for comparative catalyst B. The latter was evaluated at 100, after which a calculation of the former gave the value of the activity relative to the weight.

Table 4, results of the RWA HDN 103 RÚ HD test? 100 RÚA HDGI 110 RÚA HDCCR 97 RÚA conversion 100 From these results it follows that the catalyst A according to the invention is substantially as good as the commercially available comparative catalyst B and still shows a better HDtt. This demonstrates that it is possible to prepare a bored bed catalyst with good properties from a material discarded with the process according to the invention.

Claims (13)

NOVELTY OF THE INVENTION CLAIMS

1. A process for preparing a catalyst suitable for the hydrotreatment of heavy hydrocarbon supplies, a process consisting of the steps of I) if it is necessary to remove the carbonaceous and sulphurous deposits of the discarded catalyst by subjecting the discarded catalyst to a heat treatment , II) crush the waste catalyst obtained in step I), III) mix the ground material obtained in step II) with a binder and, optionally, additives, and IV) mold the mixture to form a new catalyst, in which the lost to the allusion of the catalyst composition mixture at any point in step II III, and IV is not greater than 70%.

2. A process according to claim 1, characterized in that the discarded catalyst is a discarded hydrotreating catalyst that can be used to treat water between hydrotreating supply materials substantially free of metal.

3. A process according to claim 1, characterized in that the discarded catalyst is a catalyst for discarded hydrotreatment that has been used to hydrolytically treat abso- lute materials for hydrotreatment containing metals, a catalyst that contains a total treatment of polluting metals. up to 15% by weight, calculated as oxide, based on the weight of the catalyst, which removed carbonaceous and sulphurous deposits by thermal treatment.

4. A process according to any of claims 1 to 3, characterized in that the lurin is used as binder material.

5. A method according to any of claims 1 to 4, characterized in that an additive is added to provide the catalyst with other properties.

6. A process according to claim 5, characterized in that the additive is diatomaceous earth, kaolin or sepiolite.

7. A process according to any of the preceding claims, characterized in that additional hydrogenation metals and / or phosphorus are added to the composition of the newly formulated catalyst.

8. A catalyst obtainable by the process of any of claims 1 to 7, having a particle diameter on the smallest cross section of less than 1.5 mm, which consists of a group VI metal in an amount 0.01-0.12 moles per 100 grams of catalyst, and / or a metal of group 8 in an amount of 0.004-0.8 moles per 100 grams of the catalyst.

9. A catalyst according to claim 8, which is a fixed-bed catalyst.

10. - A catalyst according to claim 8 which is a fixed bed catalyst.

11. A catalyst according to claim 10, which is a humid bed catalyst.

12. A process for hydraulically treating hydrocarbon deposits in which the hydrocarbon supply is contacted under fixed bed hydrotreating conditions with a catalyst in accordance with claim 9. 13.- A process for hydraulically treating hydrocarbons. wherein a hydrocarbon supply is contacted under boarded bed conditions with a catalyst in accordance with claim 11.