MXPA97010156A - Catalyst contains boro and silicon and its use in the hydrotracting of hydrocarbus loads - Google Patents

Abstract

The present invention relates to a hydrotreating catalyst comprising a support, at least one metal of the group VIB, silicon, boron, optionally at least one metal of group VIII of the periodic qualification, optionally phosphorus, optionally a halogen, as well as a preparation particular of the catalyst. The invention also relates to the use of this catalyst in the hydrotreatment of hydrocarbon charges.

Description

CATALYST CONTAINS BORON AND SILICON AND ITS USE IN THE HYDROTRACTING OF HYDROCARBON LOADS Background of the Invention The present invention relates to a hydrorefining catalyst of hydrocarbon charges, said catalyst comprises at least one metal of group VIB (group 6 according to the novel notation of the periodic classification of the elements: Handbook of Chemistry and Physics, 16 / a. edition, 1995-1996, * interior 1 / cover page), preferably molybdenum and tungsten, and optionally at least one metal from group VIII (groups 8, 9 and 10) of said classification, preferably cobalt and nickel, associated with a porous matrix that can be either an amorphous porous matrix or poorly crystallized (and generally of the oxide type). The catalyst is characterized in that it contains silicon, boron, optionally phosphorus, and optionally at least one element of group VIIA (group 17 of the halogens) and especially fluorine. The present invention also relates to the processes for the preparation of said catalyst, as well as to its use for the hydrotreatment of the Rßf.25889 hydrocarbon fillers such as the oil cuts, the cuts obtained from the coal comprising the reactions such as hydrogenation, the hydroxynitrogenation, hydrodeoxygenation, hydrodesulphurisation, hydrodesmetalization, hydrocarbon charges containing aromatic, and / or olefinic, and / or naphthenic, and / or paraffinic compounds, said charges optionally containing metals, and / or nitrogen, and / or oxygen and / or sulfur. Hydrotreating becomes increasingly important in the practice of refining with the increasing need to reduce the amount of sulfur in oil cuts and convert heavy fractions into lighter fractions that can be titrated as fuels. This results in part from the growing demand for fuels that needs to convert imported crude oil increasingly rich in heavy fractions and into heteroatoms, such as nitrogen and sulfur, and on the other hand to the specifications imposed on the sulfur content. and of aromatic substances in various countries for commercial fuels. This evaluation involves a relatively significant reduction in the molecular weight of the heavy constituents, which can be obtained, for example, by means of thermo-fractionation reactions.

Current catalytic hydroforming processes use catalysts capable of promoting the main reactions useful for giving value to heavy cuts, in particular the hydrogenation of aromatic rings (HAR), hydrodesulfurization (HDS), hydrodesnitrogenation (HDN) and other hydroeliminations. The hydrofinishing is used to treat loads such as gasolines, gas oils, gas oils under vacuum, atmospheric residues or under vacuum, deasphalted or not. For example, it is very suitable for the treatment of the loads of the thermal cracking and catalytic hydractionation processes. The heterocyclic nitrogenous compounds found in the heavy fractions behave like poisons at a very marked toxicity for the thermocracking or hydrofractionation catalysts. Accordingly, the denitrogenation of the catalytic hydrofraction fillers is one of the possible means to improve the overall performance of these processes, and it is then desirable to minimize the nitrogen content of the fillers before thermofractionation. At least one stage of the hydrorefining is usually integrated in each of the known schemes of the evaluation of heavy oil cuts.

It is thus important to increase the hydrotreating activity in the thermofraction of the hydrotreating catalysts. One of the means consists in acidifying the matrix without poisoning the activity of the hydrogenating phase based on the transition metals. The invention thus relates to a hydrotreating catalyst for hydrocarbon charges. The catalyst contains at least one metal chosen from group VIB of the periodic classification of the elements, such as chromium, molybdenum and tungsten, deferring molybdenum and tungsten, and optionally at least one metal selected from group VIII of said Classification, such as iron, cobalt, nickel, ruthenium, rhodium, palladium, osmium, iridium and platinum. The catalyst contains at least one support selected from the group consisting of amorphous, poorly crystallized supports. The catalyst is characterized in that it also contains boron, silicon, optionally phosphorus and optionally an element of group VIIA, and preferably fluorine. Said catalyst presents a hydrogenation activity of the aromatic and hydrodesnitrogenation and hydrodesulfurization hydrocarbons more important than the catalytic formulas known in the prior art. While not wishing to be bound by any theory, it appears that this particularly high activity of the catalysts of the present invention is due to the strengthening of the acidity of the catalyst by the joint presence of boron and silicon on the matrix, which induces one part an improvement of the hydrogenating, hydrodesulfurizing, hydrodenitrogenating properties and on the other hand an improvement of the activity with respect to the catalysts usually used in the hydrotreating reactions. The catalyst of the present invention contains generally in% by weight with respect to the mass-total of the catalyst at least one metal chosen from the following groups and with the following contents: 3 to 60%, preferably 3 to 45% and still more preferably from 3 to 30% of at least one metal of group VIB and, at most 30%, preferably from 0.1 to 25% and even more preferably from 0.1 to 20% of at least one metal of the group VIII, the catalyst also contains at least one support chosen from the group consisting of amorphous matrices and poorly crystallized matrices, said catalyst is characterized in that it also contains 0.1 to 20%, preferably 0.1 to 15% and still more preferred from 0.1 to 10% boron, 0.1 to 20%, preferably from 0.1 to 15% and still more preferably from 0.1 to 10% silicon. The contents higher than 1.6% (especially 1.6-10%) are often advantageous. and optionally, 0 to 20%, preferably from 0.1 to 20%, even from 0.1 to 15% and still more preferably from 0.1 to 10% of phosphorus, and optionally still, - 0 to 20%, preferably 0.1 at 20%, even from 0.1 to 15% and still more preferably from 0.1 to 10% of * at least one element chosen from the group VIIA (halogen), preferably fluorine. The metals of group VIB, group VIII of the catalyst of the present invention, may be present in whole or in part in the metallic form and / or the oxide and / or the sulfur. The catalysts according to the invention can be prepared by all suitable methods. Preferably, the silicon and boron are introduced onto the catalyst containing either the support and the metal (s) of Groups VIB and optionally of Group VIII.

Preferably, a catalyst, for example a conventional hydrotreating catalyst, of the type NiMo or NiMoP on alumina or of the type CoMo or CoMoP on alumina, is impregnated with an aqueous solution of boron then an aqueous solution of silicon (or vice versa) , a solution of silicon after boron) or is impregnated by a common aqueous solution of boron and silicon. More particularly, the method of preparing the catalyst of the present invention comprises the following steps: a) a solid subsequently named after the precursor is dried and contains at least the following compounds: an amorphous and / or crystallized porous matrix, at least one element of group VIB, and optionally at least one element of group VIII, eventually the phosphorus, preferably being put in shape, b) the solid precursor defined in step a) is impregnated with an aqueous solution containing boron and silicon and optionally at least one element of group VIIA, preferably F, c) the wet solid is allowed to stand under a humid atmosphere at a temperature between 10 and 80 ° C, d) the wet solid obtained in stage b) is dried at a temperature comprised between 60 and 150 ° C, e) the solid obtained in stage c) is calcined at a temperature comprised between 150 and 800 ° C.

The precursor defined in step a) above can be prepared according to the classical methods of the person skilled in the art. Step b) needs to place an aqueous solution containing boron and / or silicon and therefore is different from the classical B and / or Si deposition methods known to the person skilled in the art. A preferred method according to the invention is to prepare an aqueous solution of at least one boron salt such as ammonium bicarbonate or ammonium pentaborate in an alkaline medium and in the presence of hydrogen peroxide and a compound is introduced into the solution. of silicon of the silicone type and to proceed to a so-called dry impregnation, in which the volume of the pores of the precursor is filled by the solution containing B and Si. This method of depositing B and Si is better than the conventional method that uses an alcoholic solution of boric acid or a solution of ethyl orthosilicate in alcohol. The B and Si and optionally the P and optionally the element chosen from the group VIIA of the halide ions, preferably F, can be introduced into the catalyst at various levels of the preparation and in various ways. The impregnation of the matrix is preferably effected by the so-called "dry" impregnation method well known to the person skilled in the art. The impregnation can be carried out in a single step by a solution containing all the constituent elements of the final catalyst. The P, B, Si and the element chosen between the halide ions of group VIIA, can be introduced by one or several operations of impregnation with the * excess of the solution on the calcined precursor. Thus, in the preferred case where for example the precursor is a catalyst of the nickel-molybdenum type supported on alumina, it is possible to impregnate this precursor with an aqueous solution of ammonium diborate and the silicone Rhodorsil E1P of the Rhone Poulenc Company, drying, for example, at 80 ° C, then impregnating with an ammonium fluoride solution, drying at 80 ° C for example, and proceeding with a calcination, for example, and preferably under air in a bed cross section, for example at 500 ° C for 4 hours. Other impregnation sequences can be operated to obtain the catalyst of the present invention.

Thus, it is possible to first impregnate the solution containing the silicon, dry, calcinate and impregnate the solution containing the boron, dry and proceed to a final calcination. It is also possible to impregnate in a first time the solution containing boron, dry, calcine and impregnate the solution containing the silicon and dry and proceed to a final calcination. It is also possible to first impregnate the precursor with a phosphorus-containing solution, dry it, then calcine impregnate the solid * obtained with the solution containing the boron, dry, calcine and impregnate the solution containing the silicon, dry and proceed to a final calcination. In the case where the metals are introduced in various impregnations of the corresponding precursor salts, an intermediate drying step of the catalyst is generally carried out at a temperature generally comprised between 60 and 250 ° C. The preferred phosphorus source is orthophosphoric acid H3PO4, but its salts and esters such as ammonium phosphates are equally convenient. The phosphorus can be introduced, for example, in the form of a mixture of phosphoric acid and a basic organic compound containing nitrogen, such as ammonia, primary and secondary amines, cyclic imines, compounds of the pyridine family and quinolines and the compounds of the pyrrole family. Numerous sources of silicon can be used. Thus, the ethyl orthosilicate Si (OEt) 4, the siloxanes, the halide silicates such as the ammonium fluorosilicate (NH4) 2SiF6 or the sodium fluorosilicate Na2SiF6 can be used. The silicomolybdic acid and its salts, the silicotungstic acid and its salts can also be advantageously used. The silicon can be added, for example, by impregnation of the ethyl silicate in solution in a water / alcohol mixture. The boron source can be boric acid, preferably the orthoboric acid H3B03, the bibuate or the ammonium pentaborate, the boron oxide, the boric esters. Boron can be introduced for example by a boric acid solution in a water / alcohol mixture. The sources of the VIIA group element that can be used are well known to the person skilled in the art. For example, fluoride anions can be introduced in the form of hydrofluoric acid or its salts. These salts are formed with alkali metals, ammonium or an organic compound. In the latter case, the salt is advantageously formed in the reaction mixture by the reaction between the organic compound and the hydrofluoric acid. It is also possible to use hydrolysable compounds that can release fluoride anions in water, such as ammonium fluorosilicate (NH4) 2SiF6, silicon tetrafluoride SiF4 or sodium Na2SiF6. The fluorine can be introduced, for example, by impregnating an aqueous solution of hydrofluoric acid or ammonium fluoride. The sources of the group VIB element that can be used are well known to the person skilled in the art. For example, between the molybdenum and tungsten sources, oxides and hydroxides, molybdic and tungstic acids and their salts, in particular ammonium salts such as ammonium molybdate, phosphomolybdic acid, acid, can be used. phosphotungstic and its salts. Oxides and ammonium salts such as ammonium molybdate, ammonium heptamolybdate and ammonium tungstate are preferably used. The catalyst of the present invention may contain a group VIII element such as iron, cobalt, nickel. The associations of the following metals are advantageously used: nickel-molybdenum, cobalt-molybdenum, iron-molybdenum, iron-tungsten, nickel-tungsten, cobalt-tungsten, the preferred associations are: nickel-molybdenum, cobalt-molybdenum. It is also possible to use associations of three metals, for example nickel-cobalt-molybdenum. The sources of the group VIII element that can be used are well known to the person skilled in the art. For example, for non-noble metals, nitrates, sulfates, phosphates, halides, for example, chlorides, bromides and fluorides will be used., carboxylates, for example acetates and carbonates. The catalyst of the present invention thus also contains at least one porous mineral matrix which is usually amorphous or poorly crystallized. This matrix is usually chosen from the group consisting of alumina, silica, silica-alumina, magnesium, titanium oxide or zirconium oxide, or a mixture of at least two of the oxides mentioned above. You can also choose the aluminates. It is preferred to use matrices containing the alumina, under all of these forms known to the person skilled in the art, for example gamma alumina. Alumina and silica mixtures, mixtures of alumina and silica-alumina and mixtures of alumina and boron oxide can also be used advantageously.

The mixtures of alumina and argyl and the mixtures of silica-alumina and argyl can be used advantageously. The impregnation of molybdenum can be facilitated by the addition of phosphoric acid in the solutions of ammonium paramolybdate, which also allows phosphorus to be introduced in such a way that catalytic activity is promoted. Other phosphorus compounds can be used as is well known to the person skilled in the art. The catalysts obtained by the present invention are put into shape under the shape of grains of different shape and dimensions, which are generally used in the form of cylindrical and polylobed extrudates such as biloba, trilobate, polylobulated straight or twisted, but they can eventually be manufactured and used in the form of ground powder, tablets, rings, balls, wheels, etc. They have a specific surface area measured by nitrogen adsorption according to the BET method (Brunauer, Emmett, Teller, J Am. Chem. Soc., Vol 60, 309-316 (1938)) between 50 and 600 m2 / g, a porous volume measured by mercury porosimetry between 0.2 and 1.5 cm3 / g and a size distribution of the pores that can be monomodal, bimodal or polymodal.

The catalysts obtained by the present invention are used for the hydrotreatment of hydrocarbon charges such as oil cuts, coal cuts that comprise the reactions such as hydrogenation, hydrodesnitrogenation, hydrodeoxygenation, hydrodesulphurisation, hydrocarbon charges contain the aromatic, and / or olefinic, and / or naphthenic, and / or paraffinic compounds, said fillers optionally contain metals, and / or nitrogen, and / or oxygen, and / or sulfur. In these uses, the catalysts obtained by the present invention have an improved activity with respect to the prior art. The fillers used in the process are gasolines, gas oils, gas oils under vacuum, atmospheric residues, residues under vacuum, atmospheric distillates, vacuum distillates, heavy fuels, oils, waxes and paraffins, used oils, waste or unrefined deasphalted oil, the loads that come from thermal or catalytic conversion processes and their mixtures. They contain heteroatoms such as sulfur, oxygen and nitrogen and optionally at least one metal. Hydrotreatment conditions such as temperature, pressure, rate of hydrogen recycling, volumetric speed per hour, could be very variable depending on the nature of the load, the quantity of the desired products and the facilities available the refiner The temperature in general is higher than 200 ° C and frequently between 250 ° C and 480 ° C. The pressure is higher than 0.05 MPa and frequently higher than 1 MPa. The rate of recycling of hydrogen is at least 50 and is often between 80 and 5000 normal liters of hydrogen per liter of cargo. The volumetric velocity per hour is generally comprised between 0.1 and 20 volumes per volume of catalyst per hour. The catalysts of the present invention are preferably subjected to a sulphidation treatment which allows to transform, at least in part, the metal sulfide species before their contact with the charge to be treated. This activation treatment by sulfurization is well known to the person skilled in the art and can be carried out by any method already described in the literature. A classical sulfiding method well known to the person skilled in the art consists in heating the mixture of solids under the flow of a mixture of hydrogen and hydrogen sulphide or under the flow of a mixture of nitrogen and hydrogen sulfide at a temperature between 150 and 800 ° C, preferably between 250 and 600 ° C, generally in a cross-bed reaction zone. The results that matter to the refiner are especially HDS activity, HDN activity and conversion. The fixed objectives must be carried out under conditions compatible with economic reality. Thus, the refiner will seek to lower the temperature, the pressure, the hydrogen recycling rate and to maximize the volumetric speed per hour. It is known that the activity can be increased by a rise in temperature, but this often to the detriment of the stability of the catalyst. The stability or life span is improved with an increase in the pressure or the hydrogen recycling rate, but this is done to the detriment of the economy of the procedure.

Hydrodesulphurization of gasoline The catalyst of the present invention can be advantageously used for hydrodesulphurisation of cuts of the gasoline type, for reducing the sulfur content and for satisfying the standards of sulfur content in gasolines. The treated fillers have initial boiling points of at least 25 ° C, preferably of at least 30 ° C, and more advantageously it is a cut that boils at between 30 and 280 ° C.

In this mode of hydrotreatment, often called hydrodesulfurization of gasoline, pretreatment of the catalytic reforming charge or hydrodesulfurization of the gasoline of the catalytic fluid of the fractionator, the catalyst according to the invention is used at a temperature generally greater than or equal to 200. ° C, generally when much of 400. The pressure is generally higher than 0.1 MPa and preferably higher than 0.2 MPa. The amount of hydrogen is at least 50 normal liters of hydrogen per liter of charge and frequently includes between 50 and 1000 normal liters of hydrogen per liter of the load. The volumetric velocity per hour is generally comprised between 1 and 20 hours. 1 and preferably between 2-20 h "1. Under these conditions, the catalysts of the present invention contain cobalt, molybdenum, boron and silicon having a better hydrodesulfurization activity than catalysts containing cobalt and molybdenum, but which do not contain the two elements of boron and silicon as shown in Example 19 Hydrodesulphurisation of gas oil The catalyst of the present invention can be used advantageously for the hydrodesulphurisation of gasoil type cuts to reduce the sulfur content and to satisfy the sulfur content standards. The treated hydrocarbon feeds have initial boiling points of at least 80 ° C, and more advantageously it is a cut boiling between 150 and 480 ° C. In this mode of hydrotreating, often called hydrodesulfurization of gas oil, the catalyst according to the invention is used at a temperature generally greater than or equal to 250 ° C, generally at a high of 450 ° C, and often comprised between 280 ° C and 430 ° C. The pressure is generally greater than 0.2 MPa and preferably greater than 0.5 MPa. The amount of hydrogen is at most 50 standard liters of hydrogen per liter of the charge and often comprises between 80 and 1000 normal liters of hydrogen per liter of charge. The volumetric speed per hour is generally comprised between 0.1 and 20 h "1 and preferably between 0.5-15 h" 1. Under these conditions, the catalysts of the present invention contain cobalt, molybdenum, boron and silicon which have a better hydrodesulfurization activity than catalysts containing cobalt and molybdenum but which do not contain the two elements of boron and silicon as shown in example 15.

Hydrogenation of aromatic substances in gas oils The catalyst of the present invention can be advantageously used for the hydrogenation of the aromatic substances of various hydrocarbon cuts with a reduced sulfur content and for example previously already desulfurized. The treated loads are loads whose initial distillation point is higher than 80 ° C and lower than 580 ° C. They contain 1 to 2000 ppm by weight of sulfur and preferably 2 to 1500 ppm of S. This type of hydrotreatment is particularly interesting for reducing the content of aromatic substances in the light and heavy gas oil type fillers. In this mode of treatment, the catalyst according to the invention is then employed at a temperature higher generally or equal to 280 ° C, generally at most 420 ° C, and frequently comprised between 300 ° C and 400 ° C. The pressure is generally higher than 1 MPa, and preferably greater than 3 MPa. The amount of hydrogen is at least 100 normal liters of hydrogen per liter of charge and is often between 200 and 3000 normal liters of hydrogen per liter of charge. The volumetric speed per hour is generally comprised between 0.1 and 10 h "1 and preferably between 0.2-5 h -1., the catalysts of the present invention contain the molybdenum, nickel, boron and silicon which have a better hydrogenation activity of the aromatic substances than the catalysts that do not contain the two elements of boron and silicon as indicated in example 16.

Hydrotreating of distillates under vacuum The catalyst of the present invention can be advantageously used for the hydrotreating of the vacuum distillate type cuts cargadss * strongly of sulfur and nitrogen to reduce the content of sulfur and especially of nitrogen. The treated hydrocarbon feeds have initial boiling points of at least 250 ° C, preferably of at least 300 ° C, and more advantageously it is a boiling cut at between 330 ° C and 650 ° C. This type of hydrotreating is particularly interesting for pretreating the charges intended for a hydrofractionator employing one or a few zeolitic catalysts, the charges intended for the fluid catalytic thermoformer, and for effecting the hydrorefining of the oil or oil cuts. In this mode of hydrotreatment still sometimes called the pretreatment of the hydrofraction fillers, the pretreatment of the FCC fillers or the hydrorefining of the oils, the catalyst according to the invention is employed at a temperature generally greater than or equal to 300 ° C. , generally when much of 450 ° C, and frequently included between 340 ° C and 440 ° C. The pressure is generally higher than 2 MPa and preferably greater than 5 MPa. The amount of hydrogen is at least 100 normal liters of hydrogen per liter of the charge and frequently comprises between 200 and 3000 normal liters of hydrogen per liter of the charge. The volumetric velocity per hour is generally comprised between 0.1 and 5 h "1 and preferably between 0.2-4 h" 1. In these conditions, the catalysts of the present invention contain nickel, molybdenum, boron and silicon which have a better hydrodesulfurization and hydrodesnitrogenation activity than the catalysts containing molybdenum and nickel but do not contain the two boron elements and silicon as shown in example 9.

Partial hydrofraction The catalyst of the present invention can be advantageously used for the partial hydrofraction of various hydrocarbon cuts, for example the vacuum distillate type cuts heavily loaded with sulfur and nitrogen. The treated hydrocarbon feeds have initial boiling points of at least 150 ° C, preferably of at least 300 ° C, and more advantageously it is a boiling cut between 330 and 650 ° C. In this partial hydrofraction mode still sometimes called double hydrofraction, the conversion level is less than 55%. The catalyst according to the invention is then used at a temperature generally greater than or equal to 350 ° C, generally at a high level of 480 ° C, and frequently comprised between 360 ° C and 460 ° C, preferably 360-450 ° C. The pressure is generally greater than 2 MPa and preferably greater than 5 MPa. The amount of hydrogen is at least 100 normal liters of hydrogen per liter of the charge and is often between 200 and 3000 normal liters of hydrogen per liter of the charge. The volumetric velocity per hour is generally comprised between 0.1 and 5 h "1 and preferably 0.1-4 h '1. Under these conditions, the catalysts of the present invention contain boron and silicon which exhibit a better conversion activity, of hydrodesulfurization and hydrodesnitrogenation than catalysts that do not contain the two elements of boron and silicon as indicated in example 17.

Hydro-fractionation The catalyst of the present invention can also be used advantageously for the hydrofraction of various hydrocarbon cuts, for example vacuum-type cuts under high sulfur and nitrogen loading. The treated hydrocarbon fillers have initial boiling points of at least 150 ° C, preferably of at least 300 ° C, and more advantageously it is a boiling cut at between 330 and 650 ° C. In this hydrofraction mode, the conversion level is greater than 55%. The operating conditions are generally a temperature of 350-460 ° C, preferably 360-450 ° C, a pressure greater than 5 MPa, and preferably greater than 8 MPa, a volumetric velocity per hour of 0.1 to 5 h "1 and preferably 0.1-4 h" 1 and with an amount of hydrogen of at least 100 NI / 1 of the filler, and preferably 200-3000 NI / 1 of filler. Under these conditions, the catalysts of the present invention contain molybdenum, nickel, boron and silicon having a better conversion activity and selectivity in the intermediate distillates, equivalent to the catalysts that do not contain the two elements of boron and silicon as shown in example 18.

The following examples illustrate the present invention without however limiting the foregoing.

Example 1 Preparation of the alumina support that enters the composition of the catalysts of the invention.

An alumina-based support was made in a large amount so that the catalysts described below can be prepared from the same carrier-shaped support. To do this, a matrix composed of ultrafine tabular boehmite or alumina gel marketed under the name SB3 by the Condéa Chemie Gmbh Company is used. This gel has been mixed with an aqueous solution containing 66% nitric acid (7% by weight of the acid per gram of dry gel) then kneaded for 15 minutes. At the exit of the kneading, the paste obtained is passed through a row that has cylindrical holes with a diameter equal to 1.3 mm. The extruded materials are then dried overnight at 120 ° C then calcined at 550 ° C for 2 hours under humid air containing 7.5% by volume of water. Cylindrical extruded materials of 1.2 mm in diameter are thus obtained, having a specific surface area of 243 m2 / g, a porous volume of 0.61 cm3 / g and a monomodal pore size distribution centered on 100 nm. The analysis of the matrix by X-ray diffraction reveals that it is composed only of cubic gamma alumina of reduced crystallinity.

Example 2 Preparation of the NiMo / alumina precursor catalyst.

The extruded support of Example 1 is impregnated dry with an aqueous solution containing molybdenum and nickel salts. The molybdenum salt is the ammonium heptamolybdate Mo7024 (NH4) 6.4H20 and that of the nickel is the nickel nitrate Ni (N03) 2.6H20. After ripening at room temperature in a water-saturated atmosphere, the impregnated extruded materials are dried overnight at 120 ° C then calcined at 550 ° C for 2 hours under dry air. The final content of molybdenum trioxide is 14.5% by weight, which corresponds to 0.1 mol of the molybdenum element for 100 g of the finished catalyst. The final content of nickel oxide NiO is 2.8% by weight, which corresponds to 0.037 moles of the nickel element for 100 g of the finished catalyst. The catalyst A thus obtained, whose characteristics are grouped in table 1, is representative of the industrial catalysts.

Example 3 Preparation of the NiMoP / alumina precursor catalyst.

The extruded support of Example 1 has been dry impregnated with an aqueous solution containing the same salts as the solution used to prepare catalyst A of Example 2 but to which the phosphoric acid H3PO4 has been added. The same maturation, drying and calcination steps as for the preparation of catalyst A of example 2 have been used. The final content of molybdenum trioxide is 14.5% by weight, which corresponds to 0.1 mol of the molybdenum element for 100 g of the finished catalyst. The final content of nickel oxide is 2.80% by weight, which corresponds to 0.037 moles of the nickel element for 100 g of the finished catalyst. The final content of phosphorus is 6% by weight expressed in pentaoxide, which corresponds to an atomic ratio P / Mo of 0.85. The catalyst B thus obtained, whose characteristics are summarized in table 1, is representative of the industrial catalysts.

Table 1: Characteristics of catalysts A to H Example 4 Preparation of the NiMo / alumina + B + Si catalysts (according to the invention) Three catalysts, named C, D and E, have been prepared for the dry impregnation of the extruded materials of the NiMo / alumina catalyst described in example 2 (catalyst A), by the solutions respectively containing the ammonium bicarbonate, the emulsion Rhodorsil EP1 silicone and a mixture of two preceding compounds. After ripening at room temperature in a water-saturated atmosphere, the extruded materials are dried overnight at 120 ° C then calcined at 550 ° C for 2 hours under dry air. The characteristics of these three catalysts are grouped in Table 1.

Example 5 Preparation of the NiMoP / alumina + B + Si catalysts (according to the invention) Three samples of the NiMoP / alumina catalyst (catalyst B) described in example 3 have been "impregnated by the same solutions containing either B, or Si or B + Si, and according to the same protocol as the NiMo / alumina catalyst in example 4. It is prepared in this way a catalyst named F of the formula NiMoPB / alumina, a catalyst G of the formula NiMoPSi / alumina and a catalyst H of the formula NiMoPBSi / alumina whose proportions among the various elements Ni, Mo, P, B or Si and the characteristics are summarized in table 1.

Example 6 Preparation of the NiMoP / alumina + F + B + Si catalysts (according to the invention) The ammonium fluoride has been reaggregated to an aqueous solution containing the ammonium biborate and the Rhodorsil EP1 silicone emulsion so that the catalyst A, NiMo / alumina, described in the example is obtained by dry impregnation of the extruded materials. 2, a catalyst I of the formula * NiMoFBSi / alumina containing 1% by weight of fluorine and the proportions of Ni, Mo, B and Si indicated in table 1. The same stages of maturation, drying and calcination as for the preparation of catalyst A of example 2 have been used. In the same manner and with the same solution, a volume of the extruded materials of catalyst B, NiMoP / alumina, described in example 3 has been impregnated. The catalyst J thus obtained, of the NiMoPFBSi / alumina formulation, contains 1% by weight of fluorine. The characteristics of the two catalysts I and J are grouped in table 2.

Table 2: Characteristics of the NiMo I to S catalysts Example 7 Preparation of the NiMo / Alumina B + Si catalysts (according to the invention) Three samples of the support described in Example 1 are impregnated dry by means of an aqueous solution containing the ammonium bibuate. After ripening at room temperature in a water saturated atmosphere, the impregnated extruded materials are dried overnight at 120 ° C then calcined at 550 ° C for 2 hours under dry air. The extruded alumina materials contaminated with boron thus obtained were immediately impregnated with a solution containing the ammonium heptamolybdate Mo7024 (NH4) e.4H20 and the nickel nitrate Ni (N03) 2.6H20. After maturation, drying and calcination at 550 ° C as above, a catalyst named K: NiMO / alumina doped with boron is obtained. The final contents of Mo, Ni and B correspond to those of the catalyst C described in example 4. A catalyst L was obtained by the same procedure as the previous catalyst K but replacing the boron precursor with the emulsion in the impregnation solution. of silicone Rhodorsil EP1. The catalyst thus obtained: NiMo / alumina doped with silicon has the same mass composition as catalyst D described in the example. Finally, a catalyst M has been obtained by the same procedure as the previous catalyst K but using an aqueous solution containing the ammonium biborate and the silicone emulsion Rhodorsil EP1. The final contents of Mo, Ni, B and Si of the catalyst M are the same as those of the catalyst E described in example 4. The characteristics of the catalysts K, L and M are summarized in table 2.

Example 8 Preparation of the silica-alumina support.

A support of the silica alumina type was manufactured by coprecipitation. After coprecipitation the solid is filtered, dried 4 hours at 120 ° C under dry air. A gel is thus obtained which is mixed with an aqueous solution containing 66% nitric acid (7% by weight of acid per gram of dry gel) but kneaded for 15 minutes. At the exit of this kneading, the paste obtained is passed through a row that has cylindrical holes with a diameter equal to 1.3 mm. The extruded materials are then dried overnight at 120 ° C then calcined at 550 ° C for 2 hours under humid air containing 7.5% by volume of water. Cylindrical extruded materials of 1.2 mm in diameter are thus obtained, having a specific surface area of 223 m2 / g, a porous volume of 0.51 cm3 / g and a monomodal pore size distribution centered on 9 nm. The composition of these extruded materials is 5.2% by weight of SiO2 and 94.8% by weight of A1203.

Example 9 Preparation of catalysts supported on silica-alumina The extruded support of Example 8 is impregnated dry with an aqueous solution containing the molybdenum and nickel salts. The molybdenum salt is the ammonium heptamolybdate Mo7024 (NH4) 6.4H20 and that of the nickel is the nickel nitrate Ni (N03) 2.6H20. After ripening at room temperature in a water-saturated atmosphere, the impregnated extruded materials are dried overnight at 120 ° C then calcined at 550 ° C for 2 hours under dry air. The catalyst P thus obtained, whose characteristics are grouped in table 2, is representative of the industrial catalysts. In the same way, the extruded support of Example 8 is impregnated dry by an aqueous solution containing the molybdenum, nickel and phosphorus salts. The molybdenum salt is the ammonium heptamolybdate Mo024 (NH4) 6. H20, that of nickel is that of nickel nitrate Ni (N03) 2.6H20 and phosphorus is added in the form of phosphoric acid. After ripening at room temperature in a water-saturated atmosphere, the impregnated extruded materials are dried overnight at 120 ° C then calcined at 550 ° C for 2 hours under dry air. The catalyst R thus obtained, whose characteristics are grouped in table 2, is representative of industrial catalysts.

Example 10 Preparation of NiMo / silica-alumina catalysts containing boron.

The catalyst P obtained in Example 9 is impregnated dry with an aqueous solution containing the ammonium diborate. After ripening at room temperature in a water-saturated atmosphere, the impregnated extruded materials are dried overnight at 120 ° C then calcined at 550 ° C for 2 hours under dry air. The catalyst Q is thus obtained, the characteristics of which are grouped in Table 2. The catalyst R obtained in Example 9 is impregnated dry by an aqueous solution containing the ammonium diborate. After ripening at room temperature in an atmosphere saturated with water, the impregnated extruded materials are dried overnight at 120 ° C then calcined at 550 ° C for 2 hours under dry air. The catalyst S is thus obtained, the characteristics of which are grouped in Table 2.

Example 11: Hydrogenation and acidity tests on model molecules; Hydrogenation of toluene, isomerization of cyclohexane The catalysts A to S, described above, are sulfided in situ in a dynamic manner in the tubular reactor of a transverse fixed bed of a pilot unit of the Catatest type (constructsr-Géomécanique), the fluids circulate from the top to the bottom. The measurements of the hydrogenating and isomerizing activity are carried out immediately after the sulphuration under pressure without encircling the air with the hydrocarbon charge that has served to sulphide the catalysts. The sulphidation and test load is composed of 5.8% dimethyl disulfide (DMDS), 20% toluene and 74.2% cyclohexane by weight. The stabilized catalytic activities of the equal volumes of catalysts A to S in the hydrogenation reaction of toluene are thus measured. The monitoring of the isomerization of cyclohexane, toluene diluent, allows to evaluate the acidity of the catalysts.

The measurement conditions of the activity are the following: Total pressure: 6.0 MPa Toluene pressure: 0.38 MPa Cyclohexane pressure: 1.55 MPa Hydrogen pressure: 3.64 MPa H2S pressure: 0.22 MPa Catalyst volume: 40 ce Load flow rate: 80 cc / h Space velocity per hour: 2 1/1 / h "1 Hydrogen flow: 36 1 / h Sulphuration and test temperature: 350 ° C (3 ° C / minute) Samples of the liquid effluent are analyzed by gas phase chromatography. The determination of the molar concentration of the unconverted toluene (T) and the concentrations of its hydrogenation products: methylcyclohexane (MCC6), ethylcyclopentane (EtCC5) and dimethylcyclopentane (DMCC5) allows calculation of a hydrogenation rate of toluene XHYD defined by: XHYD < %) - 100 • < M8C6 + EICC5 + DMCCS) (T + MCC6 + EtCC5 + DMCC5) The isomerization rate of cyclohexane Xiso is calculated in the same way from the concentrations of unconverted cyclohexane and its reaction product, methylcyclopentane. The reaction of hydrogenation of toluene and the isomerization of cyclohexane are of the order of 1 under the test conditions and the reactor behaves like an ideal piston reactor, the hydrogenating activity AH? D and isomerizing A? S0 of the catalysts is calculated by applying the formula: Table 3 compares the hydrogenating and relative isomerizing activities, equal to the ratio of activity of the catalyst considered on the activity of catalyst A taken as reference.

TABLE 3: Activities related to hydrogenation and isomerization of NiMo A to S catalysts Table 3 shows the progress made by catalysts E, H, I and J for which both boron and silicon have been added to the catalyst. This association of B and Si allows to obtain a reinforcement at the same time of the hydrogenating and acidity function of the catalyst. The addition of boron (catalysts C and F) or of silicon (catalysts D and G) alone does not allow obtaining a gain at the same time on the hydrogenating and acidity function of the catalyst. The K, L and M catalysts for which B, Si and B + Si have been introduced with the alumina, respectively, before the deposit of the active phase of NiMo, are less active in the hydrogenation than their counterparts C, D and E. In the same way, the acidity of catalysts K, L and M indicated by its isomerizing activity is improved with respect to catalyst A but remains lower than the isomerizing activity of its homologs, catalysts C, D, E. Table 3 shows that the incorporation of silicon, boron or silicon and boron, must be done after the deposit of the active phase (catalysts C, D, E) and not before (catalysts K, L, M) to obtain a reinforcement simultaneously of the hydrogenating activity and the isomerizing activity, ie of the acidity. Table 3 also shows the interest of introducing the silicon onto a catalyst already manufactured and the advantage that it has to use this method of preparation rather than from a support based on silica-alumina. Also the catalysts of example 9 based on silica-alumina containing boron such as catalyst Q, have a composition very close to the composition of catalyst E but a particularly lower hydrogenating activity. The level of the isomerizing activity of the catalyst Q is high but also a little lower than the catalyst H. The same result is found for the catalysts S and H which also contain phosphorus. This is due to the formation of a less active active phase on a silica-alumina support than on alumina, which is well known to the person skilled in the art. The addition of boron thus has a very reduced effect on the catalyst containing a silica-alumina support than the joint addition of boron and silicon onto a catalyst having an alumina support.

Example 12 Hydrotreating test of a vacuum distillate The catalysts A, B, F and H described above have also been combined in the hydrotreating test of a vacuum distillate whose main characteristics are given in the following table: Density at 15 ° C: 0.938 Sulfur - 3. 12% weight Total nitrogen: 1050 ppm by weight Simulated distillation at 345 ° C 10% 412 ° C 50% 488 ° C 90% 564 ° C PF 615 ° C The test is carried out in an isothermal pilot reactor with a fixed transverse bed, the fluids circulate from the top to the bottom. After sulphuring in situ at 350 ° C in the unit under pressure by means of a direct distillation gas oil, to which 2% by weight of the dimethyl disulfide is added, the hydrotreating test has been carried out under the conditions following operations: Total pressure 12 MPa Catalyst volume 40 cm3 Temperature 380 ° C Hydrogen flow rate 24 1 / h Load flow rate 20 cmVh The catalytic operations of the catalysts tested are given in Table 4 below.

They are expressed in relative activity, establishing that those of catalyst A are equal to 1 and considering that they are of the order of 1.5. The relationship that relates the activity and the conversion of hydrodesulfurization (% HDS) is as follows: The same ratio is applicable for hydrodesnitrogenation (% HDN and AHDN) • On the other hand, the net conversion of the fraction of the charge having a boiling point higher than 380 ° C (% 380 ° C + by weight) is also evaluated. obtained with each catalyst. It is expressed from the results of simulated distillation (ASTM method D86) for the relationship: Conv 380'C + = (8 &) ** *, (% 3Wf > C +) ° * ^ (% 380 ° C +) load TABLE 8 Activity of NiMo catalysts in vacuum distillation hydrotreating The results of Table 8 indicate that the addition of boron and silicon to a catalyst containing an element of group VIB and at least one non-noble element of group VIII supported on an amorphous oxide matrix obtained according to the methods of the invention, they significantly improve the performance of the hydrodesulphurisation catalyst, the hydrodesnitrogenation and the conversion of the 380 ° C + fraction in the light cutting boiling at a temperature lower than 380 ° C. It is especially observed that a catalyst S, of composition very similar to the catalyst H, obtained by the addition of B to a catalyst R containing a NiMo phase on a silica-alumina and containing the P is less good in HDS, in HDN and in the conversion, than the catalyst H. This is due to the dispersion of a smaller degree of the active phase of NiMo on a silica-alumina support than on an alumina support as is well known to the person skilled in the art. The catalyst H containing boron and silicon is thus particularly interesting for use in hydrotreating processes which contemplate pretreating the hydrofraction charges of the vacuum distillate type because the improved activity in hydrodesnitrogenation allows a hydrofraction loading to be obtained which has a reduced sulfur content. The catalyst H containing boron and silicon is also of particular interest for use in hydrotreating processes which contemplate pretreating catalytic fractionation charges of the vacuum distillate type because the improved hydrodesulfurization activity of hydrodesnitrogenation and the conversion allows to obtain a load of the most reactive catalytic fractionator. The catalyst H containing boron and silicon is also of particular interest for use in the hydrofinishing processes because the improved activity of hydrodesulfurization, hydrodesitrogenation and conversion makes it possible to obtain technical or medicinal oils for the specifications.

Example 13 Preparation of the CoMo / alumina precursor catalyst The extruded support of Example 1 is impregnated dry by an aqueous solution containing molybdenum and cobalt salts. The molybdenum salt is the ammonium heptamolybdate Mo7024 (NH4) 6.4H20 and that of the cobalt is the cobalt nitrate Co (N03) 2.6H20. After ripening at room temperature in a water-saturated atmosphere, the impregnated extruded materials are dried overnight at 120 ° C then calcined at 550 ° C for 2 hours under dry air. The ACo catalyst thus obtained, whose characteristics are grouped in table 9, is representative of industrial catalysts.

Example 14 Preparation of the CoMoP / alumina precursor catalyst The extruded support of Example 1 is impregnated dry by an aqueous solution containing the same salts as the solution used to prepare the ACo catalyst of Example 13 but to which the phosphoric acid H3P04 has been added. The same maturation, drying and calcination steps have been used for the preparation of the ACo catalyst of Example 13. The BCo catalyst thus obtained, whose characteristics are summarized in the table Table 9: Characteristics of catches of C0M0.

Example 15 Preparation of a CoMo / alumina catalyst + B + YES (according to the invention) A catalyst, called ECo, has been prepared by dry impregnation of the extruded CoMo / alumina catalyst materials described in Example 13 (ACo catalyst), by a solution containing a mixture of ammonium diborate and an emulsion. of silicone Rhodorsil EP1. After ripening at * room temperature in a water-saturated atmosphere, the impregnated extruded materials are dried overnight at 120 ° C then calcined at 550 ° C for 2 hours under dry air. The characteristics of this catalyst are grouped in table 9.

Example 16 Preparation of a CoMoP / alumina + B + Si catalyst (according to the invention) A sample of the CoMoP / alumina catalyst (catalyst BCo) described in example 14 has been impregnated by the same solutions containing B + Si, and according to the same prototype as the CoMo / alumina catalyst in example 15, A catalyst called HCo of the formula CoMoPBSi is thus prepared whose proportions between the various elements of Co, Mo, P, B or Si and the characteristics are summarized in table 9.

Example 17 Preparation of a CoMoP / alumina catalyst + F + B + YES (according to the invention) The ammonium fluoride has been added to an aqueous solution containing ammonium diborate and a Rhodorsil EP1 silicone emulsion so that the ACo, CoMo / alumina catalyst described in the example is obtained by dry impregnation of the extruded materials. 13, an ICo catalyst of the formula CoMoFBSi / alumina whose proportions of Co, Mo, B and Si are indicated in table 10. The same stages of maturation, drying and calcination as for the preparation of the catalyst of example 15 have been used. In the same manner and with the same solution, a volume of extruded materials of the BCo catalyst, CoMoP / alumina, described in example 14 has been impregnated. The JCo catalyst thus obtained has a CoMoPBFSi / alumina formulation. The characteristics of the two ICo and JCo catalysts are grouped in Table 10.

Table 10: Characteristics of the catalysts of C0M0, ICo and JCo Example 18 Hydrosulfurization tests of diesel fuel The supported catalysts described in Examples 13 to 17 have been compared in the hydrodesulfurization test of diesel in a pilot unit with a fixed transverse bed operating in the "upward flow" mode, ie the load circulates from below to above. The main characteristics of the load are given in the following table: Density at 15 ° C 0.856 Refractive index at 20 ° C 1.4564 Viscosity at 50 ° C 3.72 cSt Sulfur 1.57% by weight Simulated distillation Pl 153 ° C 5% 222 ° C 50% 315 ° C 95% 415 ° C PF 448 ° C The diesel HDS test is carried out under the following operating conditions: Total pressure 3 MPa Catalyst volume 40 cm3 Temperature 340 ° C Hydrogen flow 20 1 / h Load flow rate 80 cm3 / h Each of the catalysts is sulfided before the test at 350 ° C, and at a total pressure of 3 MPa for the gas oil described, below which 2% by weight of Dimethyl Disulfide (DMDS) have been added. The catalytic operations of the catalysts tested are given in table 11 below. The activity is calculated considering that the reaction is of the order of 1.5. The equation that relates the activity and the conversion (% HDS) is then the following: 100 AHDS = [.5-1 (100-% HD5) with:% HDS = 100 [S load - S effluent] S effluent In table 11 the activities are expressed in the relative activity, admitting or assuming that the one of the catalyst ACo is equal to 1.

TABLE 11 Activity of diesel hydrosulfurization catalysts In Table 11, it is observed that the operation of hydrodesulfurization of the diesel fuel of the catalysts containing both the boron and the silicon is in each case superior to the operation of the catalyst that does not contain these two elements. This has the advantage of associating boron and silicon. This advantage is remarkable when the catalyst contains P (HCo and JCo), but it is even more important when the catalyst does not contain the P (ECo and ICo). In all cases the presence of fluoride further increases hydrodesulfurization activity, and here again, the results are better in the absence of phosphorus. The results of table 11 thus indicate that the addition of boron and silicon to a catalyst containing at least one element of group VIB and at least one non-noble element of group VIII supported on an amorphous oxide matrix obtained according to the methods of The invention greatly improves the performance of the hydrodesulfurization catalyst of gas oil cuts.

Example 19 Hydrogenation test of aromatic substances in gas oils The supported catalysts A, B, F and H of the NiMo type described above in Examples 2, 3 and 5 have been compared in the test for the hydrogenation of the aromatic substances in a gas oil. The test load is a gas oil from the fluid catalytic fractionator or the LCO previously desulfurized so that they contain only a reduced sulfur content. The main characteristics of this desulfurized gas oil are given in the following table: Density at 20 ° C 0.904 Sulfur (ppm) 109 Nitrogen (ppm) 132 D86 (° C) Pl 166 10% 210 50% 266 90% 343 PF 415 Aromatic substances (% by weight) Total 74 Mono 44 Di 27 Tri 3 CA by RMN 43 It will be noted in this table that the desulphurized gas oil contains no more than 109 ppm of sulfur, a significant nitrogen content of 132 ppm and a very high content of aromatic substances. The hydrogenation test of the aromatic substances is carried out in a pilot unit with a fixed transverse bed operating in an "upward flow" mode, ie the load circulates from bottom to top under the following operating conditions: Total pressure 9 MPa Catalyst volume 40 cm3 Temperature 340 ° C Hydrogen flow rate 40 1 / h Flow rate 40 cm / h Each of the catalysts is sulfided prior to the test at 350 ° C, and at a total pressure of 9 MPa for the diesel described above to which 2% by weight of dimethyl disulfide (DMDS) has been added. The catalytic operations of the catalysts tested are given in Table 12 below. For each experiment, the density of the liquid effluent at 20 ° C, the CA content (Aromatic Carbon measured by NMR) of the effluent and the initial CA0 content of the load were measured. of the effluent, the conversion of the aromatic substances (% HAR) was calculated after the hydrogenating activity admitting or assuming that it is of the order of 1. ,, roo The activity of hydrodesulfurization was also determined. The activity is calculated considering that the reaction is of the order of 1.5. The equation that relates the activity and the conversion (% HDS) is then the following: 100 AHDS = [(100 -? Or HDS) 1M-1 The activity was also determined during hydrodesnitrogenation. The activity is calculated considering that the reaction is of the order of 1. The equation that relates the activity and the conversion of the nitrogenous product (% HDN) is then the following: 100 AHDN = Ln ((100 -% HDN)) In table 12, the activities are expressed in relative activity, assuming that that of catalyst A is equal to 1.

TABLE 12 Activity of the hydrogenation catalysts of the aromatic substances in a desulfurized gas oil The results of Table 12 indicate that the addition of boron and silicon to a catalyst containing an element of group VIB and at least one non-noble element of group VIII, supported on an amorphous oxide matrix obtained according to the methods of the invention , significantly improve the operation of the hydrogenation catalyst of the aromatic substances in a desulfurized gas oil of the desulfurized LCO type. It is also observed that the functions of desulphurisation and denitrogenation are likewise improved. - • The catalyst H containing boron and silicon is particularly interesting for use in the hydrotreating processes of fillers of the desulphurized type already desulphurised up to sulfur contents of less than 700 ppm, the object of which is to reduce the content of sulfur, or decrease the nitrogen content or even reduce the content of aromatic substances.

Example 20 Tests of partial hydrofraction of a vacuum distillate The catalysts A, B, F and H whose preparations are described in the preceding examples 2, 3 and 5 are used under the conditions of mild hydrofraction on an oil charge of the distillate type under vacuum of a large sulfur and nitrogen content whose main characteristics are the following: Density at 15 ° C 0.921 Sulfur 2.46% weight Total nitrogen 1130 ppm by weight Simulated distillation Pl 365 ° C 10% 430 ° C 50% 472 ° C 90% 504 ° C PF 539 ° C The catalytic test unit comprises a fixed bed, upwardly flowing bed reactor ("upflow"). The partial hydrofraction test is carried out under the following operating conditions: Total pressure 5 MPa Catalyst volume 40 cm3 Temperature 380 to 420 ° C Hydrogen flow rate 10 1 / h Load flow rate 20 cm3 / h Each of the catalysts is sulfurized prior to the test at 350 ° C, and at a total pressure of 5 MPa * for the gas oil described in example 15 to which 2% by weight of the dimethyl disulfide (DMDS) has been added. The catalytic performances are expressed for the crude conversion at 400 ° C (CB), for the gross selectivity of the intermediate distillates (SB) and for the conversions of the hydrodesulfurization (HDS) and the hydrodesnitrogenation (HDN). These catalytic operations are measured on the catalyst after a period of stabilization, generally of at least 48 hours, has been respected. The gross conversion CB is taken as equal to: CB =% by weight of 380 ° C minus that of the effluent The gross selectivity SB of the average distillates is taken as equal to: SB = 100 *? That of the fraction (150 ° C -380 ° C) / weight of the fraction of 380 ° C minus that of the effluent The conversion in hydrodesulfurization HDS is taken as equal to: HDS = (Sinicia? - Sefiuente) / Sinicial * 100 = (24600 - Sefluent) / 24600 * 100 The conversion of hydrodesnitrogenation HDN is taken as equal to: HDN = (Ninicial - Nefluent) / Ninicia? * 100 - (1130 - Nefluent) / 1130 * 100 In table 13 below, the crude CB conversion at 400 ° C, the gross selectivity SB, the HDS hydrodesulfurization conversion and the HDN hydrodesitrogenation conversion for the catalysts tested under these conditions have been reported.

TABLE 13 Activity of the soft hydrotreating catalysts in a vacuum distillate The results of table 13 indicate that the addition of boron and silicon to a catalyst containing an element of group VIB and of at least one non-noble element of group VIII, supported on an amorphous oxide matrix obtained according to the methods of invention, substantially improves the performance of the conversion catalyst of the fraction of 380 ° C plus that of the fraction of 380 ° C less, which is difficult to perform on this type of the load with a large sulfur content. It is also observed in Table 13 that the gross selectivity remains equivalent. The catalyst H containing boron and silicon is thus particularly interesting for use in hydrotreating processes which convert the fillers of the distillate type under vacuum with a large content of sulfur and nitrogen, called mild or partial hydrofraction, to a moderate hydrogen pressure.

Example 21 Tests of hydrofraction of a distillate under vacuum at high conversion The catalysts A, B, F and H whose preparations are described in examples 2, 3 and -5-above are used under the conditions of hydrofractionation with a high conversion (60-100%) on an oil charge of the type of the distillates under vacuum with a high content of sulfur and nitrogen whose main characteristics are the following: Density at 15 ° C 0.912 Sulfur 2.22% by weight Total nitrogen 598 ppm by weight Simulated distillation Pl 345 ° C 10% 375 ° C 50% 402 ° C 90% 428 ° C PF 467 ° C The catalytic test unit comprises a reactor of fixed bed, of upward circulation of the load ("flow upwards"). The hydrofraction test is carried out under the following operating conditions: Total pressure 20 MPa Catalyst volume 40 cm3 Temperature 380 to 420 ° C Hydrogen flow rate 24 1 / h Load flow rate 20 cm3 / h - - Each of the catalysts is sulfided before the test at 350 ° C, and at a total pressure of 20 MPa for the charge to which 2% by weight of dimethyl disulfide (DMDS) has been added. Under these conditions, the catalytic operations of hydrodesulfurization (HDS) and hydrodesnitrogenation (HDN) are such that the sulfur (S <10 ppm) and nitrogen (N < 2 ppm) in the effluent are lower than the limit of detection of standard analysis techniques. This observation is normal considering the high pressure of the hydrogen used. It is of interest then mainly the activity of the conversion of the fraction of 380 ° cma3 that is to say for the crude conversion (CB). These catalytic operations are measured on the catalyst after a period of stabilization, generally of at least 48 hours, has been respected. The gross conversion CB is taken as equal to: CB =% weight of 380 ° C minus that of the effluent In table 14 below, the CB crude conversion at 410 ° C has been reported for the catalysts tested under these conditions.

TABLE 14 Activity of the high pressure hydrofraction catalysts of a vacuum distillate The results of Table 14 indicate that the addition of boron and silicon to a catalyst containing an element of group VIB and at least one non-noble element of group VIII, supported on an amorphous oxide matrix obtained according to the methods of the invention which substantially improve the operations of the catalyst in the conversion of the fraction of 380 ° C plus that of the fraction of 380 ° C less, which is difficult to perform on this type of the load with a strong sulfur content. The catalyst H containing boron and silicon is thus particularly interesting for use in the hydrofraction processes of the fillers of the vacuum distillate type with a high content of sulfur and nitrogen, generally referred to as hydrofraction with the aid of the * amorphous catalyst, at a high hydrogen pressure.

Example 22 Tests of hydrodesulfurization of gasoline The above-supported CoMo catalysts described in Examples 10 to 14 have been compared in the FCC gasoline hydrodesulfurization test in a pilot fixed-bed transverse unit operating in an "up-flow" mode ie. the load circulates from bottom to top. The main characteristics of the load are given in the following table: Density at 22 ° C 0.735 Sulfur 230 ppm S mercaptans 69 ppm Olefins (GC) 26.8% weight Diolefins (GC) 1.15% weight bromine index (g / 100g) 47 Simulated distillation Pl 53 ° C PF 168 ° C The HDS gasoline test is carried out "under the following operating conditions: Total pressure 6 MPa Catalyst volume 25 cm3 Temperature 250 ° C Hydrogen flow 60 Nl / h Load flow 200 cm3 / h Each of the catalysts is sulfided before the test at 350 ° C for 4 hours, and at a total pressure of 6 MPa for a mixture containing 2% by weight of Dimethyl Disulfide (DMDS) in the n-heptane and with a WH of 1 h-1 and a flow rate of 350 NI of H2 per liter of the load.

The catalytic operations of the catalysts tested are given in Table 15 below.

Operation is indicated for the percentage of sulfur taken or carried.

TABLE 15 Activity of gasoline hydrodesulfurization catalysts In table 15, it is observed that the operation of hydrodesulfurization of gasoline, of the catalysts containing both boron and silicon, is superior in each case to the operation of catalysts that do not contain the two elements. There is thus an advantage of associating boron and silicon. This advantage is remarkable when the catalyst contains P (HCo and JCo) but is even more important when the catalyst does not contain P (ECo and ICo). In all cases the presence of fluoride further increases the activity in hydrodesulphurization, and here also, the results are better in the absence of phosphorus. The results of table 15 thus indicate that the addition of boron and silicon to a catalyst containing at least one element of group VIB and at least one non-noble element of group VII supported on an amorphous oxide matrix obtained according to the methods of The invention greatly improves the operation of the hydrodesulfurization catalyst of gasolines.

It is noted that in relation to this date the best method known by the applicant to carry out the aforementioned invention, is that which is clear from the present description of the invention.

Having described the invention as above, property is claimed as contained in the following

Claims (20)

1. A catalyst containing at least one metal selected from the group consisting of the metals of group VIB of the periodic classification of the elements, and which also contains at least one metal from group VIII of the periodic classification of the elements, said metals are deposited on a support, the catalyst is characterized in that it comprises silicon and boron.

2. The catalyst according to one of claims 1 and 2, characterized in that it also contains phosphorus.

3. The catalyst according to one of claims 1 to 2, characterized in that it also contains a halogen.

4. The catalyst according to claim 3, characterized in that the halogen is fluorine.

5. The catalyst according to one of claims 1 to 4, characterized in that it contains, by weight with respect to the total mass of the catalyst: 3 to 60%, of a metal of group VIB, at most 30%, of a metal of group VIII , at least one support chosen from the group consisting of amorphous, poorly crystallized supports - 0.1 to 20% boron, 0.1 to 20% silicon 0 to 20% phosphorus 0 to 20% of at least one element of group VIIA.

6. The catalyst according to claim 5, characterized in that the catalysed-r * contains in weight 3 to 45% of a metal of group VIB, preferably of 3 to 30%.

7. The catalyst according to claim 5, characterized in that the catalyst contains by weight 0.1 to 25% of a metal of group VIII.

8. The catalyst according to one of claims 1 to 7, characterized in that the boron content is between 0.1 to 15% by weight, preferably 0.1 to 10% by weight and that of silicon is between 0.1 to 15% by weight. weight, preferably from 0.1 to 10% by weight.

9. The catalyst according to one of claims 1 to 8, characterized in that it also contains 0.1 to 20% phosphorus.

10. The catalyst according to claim 9, characterized in that it also contains 0. 1 to 15% by weight and preferably 0.1 to 10% by weight of phosphorus.

11. The catalyst according to one of claims 1 to 10, characterized in that it contains, by weight, 0.1 to 20% of a halogen.

12. The catalyst according to claims 1 to 10, characterized in that it contains by weight 0.1 to 20% of fluorine.

13. The process for manufacturing a catalyst according to one of claims 1 to 12, characterized in that it is introduced singly or together, on a catalytic mass still called the precursor based on an amorphous porous matrix containing at least one metal from the group VIB, at least one metal of group VIII, and optionally phosphorus, at least one solution containing boron and at least one solution containing silicon.

14. The use of a catalyst according to one of claims 1 to 12 or prepared according to claim 13, in a refining or hydroconversion reaction of the hydrocarbon feeds.

15. The use of a catalyst according to one of claims 1 to 12 or "prepared according to claim 13, in a hydrodesulfurization reaction of gasoline, at a temperature greater than or equal to 200 ° C, with a pressure greater than 0.1 MPa and preferably greater than 0.2 MPa, with an amount of hydrogen comprised between 50 and 1000 normal liters of hydrogen per liter of charge and with a volumetric velocity per hour comprised between 1 and 20 h "1 and preferably between 2 and 20 h" 1.

16. The use of a catalyst according to one of claims 1 to 12 or prepared according to claim 13, in a hydrodesulfurization reaction of gas oil, at a temperature greater than or equal to 250 ° C, lower than 450 ° C and preferably comprised between 280 ° C and 430 ° C, with a pressure greater than 0.2 MPa and preferably greater than 0.5 MPa, with an amount of hydrogen greater than or equal to 50 normal liters of hydrogen per liter of the load, preferably comprised between 80 and 1000 normal liters of hydrogen per liter of load, with a volumetric speed per hour comprised between 0.1 and 20 h-1, preferably between 0.5 and 15 h "1.

17. The use of a catalyst according to one of claims 1 to 12 or prepared according to claim 13, in a de-hydrogenation reaction of the aromatic substances in the gas oils, at a temperature greater than or equal to 280 ° C, lower than 420 ° C and preferably between 300 ° C and 400 ° C, with a pressure greater than 1 MPa and preferably greater than 3 MPa, with an amount of hydrogen greater than or equal to 100 normal liters of hydrogen per liter of the charge, preferably comprised between 200 and 3000 normal liters of hydrogen per liter of the load, with a volumetric velocity per hour comprised between 0.1 and 10 h "1, preferably comprised between 0.2 and 5 h" 1.

18. The use of a catalyst according to one of claims 1 to 12 or prepared according to claim 13, in a hydrotreating reaction of the distillates under vacuum, at a temperature greater than or equal to 300 ° C, lower than 450 ° C and preferably between 340 ° C and 440 ° C, with a pressure greater than 2 MPa and preferably greater than 5 MPa, with an amount of hydrogen greater than or equal to 100 normal liters of hydrogen per liter of charge, preferably between 200 and 3000 normal liters of hydrogen per liter of load, with a volumetric speed per hour comprised between 0.1 and 5 h "1, preferably between 0.2 and 4 h" 1.

19. The use of a catalyst according to one of claims 1 to 12 or prepared according to claim 13, in a reaction of partial hydrofraction of hydrocarbon cuts, at a temperature greater than or equal to 350 ° C, lower than 480 ° C and preferably comprised between 360 ° C and 460 ° C, with a pressure greater than 2 MPa and preferably greater than 5 MPa, with an amount of hydrogen greater than or equal to 50 normal liters of hydrogen per liter of the load, preferably comprised between 100 and 3000 normal liters of hydrogen per liter of the load, with a volumetric speed per hour comprised between 0.1 and 5 h "1, preferably comprised between 0.1 and 4 h" 1.

20. The use of a catalyst according to one of claims 1 to 12 or prepared according to claim 13, in a hydrofraction reaction of the hydrocarbon cuts, at a temperature comprised between 360 ° C and 450 ° C, with a higher pressure at 5 MPa and preferably greater than 8 MPa, with an amount of hydrogen greater than or equal to 100 normal liters of hydrogen per liter of the charge, preferably comprised between 200 and 3000 normal liters of hydrogen per liter of the charge, with a volumetric speed per hour comprised between 0.1 and 5 h-1, of "preference between 0.5 and 4 h" 1.