FR3105931A1 - CATALYST BASED ON 2-HYDROXY-BUTANEDIOIC ACID OR 2-HYDROXY-BUTANEDIOIC ACID ESTERS AND ITS USE IN A HYDROTREATMENT AND / OR HYDROCRACKING PROCESS - Google Patents

Abstract

The subject of the invention is a catalyst comprising a support based on alumina or on silica or on silica-alumina, at least one element from group VIII, at least one element from group VIB, and an organic compound of formula (I). in which: - R1 is a hydrocarbon radical comprising from 1 to 12 carbon atoms, saturated or not, linear, branched or cyclic, - X is chosen from a hydrocarbon radical comprising from 1 to 12 carbon atoms, saturated or not, linear , branched or cyclic, a hydrogen atom and an alcohol function.

Description

CATALYST BASED ON 2-HYDROXY-BUTANEDIOIC ACID OR 2,3-HYDROXY-BUTANEDIOIC ACID ESTERS AND ITS USE IN A HYDROTREATING AND/OR HYDROCRACKING PROCESS

The invention relates to a catalyst additive with an organic compound, its method of preparation and its use in the field of hydrotreating and/or hydrocracking.

Usually, a catalyst for the hydrotreatment of hydrocarbon cuts aims to eliminate the sulfur or nitrogen compounds contained therein in order to bring, for example, a petroleum product to the required specifications (sulphur content, aromatic content, etc.) for a given application (vehicle fuel, gasoline or diesel, heating oil, jet fuel).

Conventional hydrotreating catalysts generally comprise an oxide support and an active phase based on Group VIB and VIII metals in their oxide forms as well as phosphorus. The preparation of these catalysts generally includes a step of impregnation of metals and phosphorus on the support, followed by drying and calcination to obtain the active phase in their oxide forms. Before their use in a hydrotreating and/or hydrocracking reaction, these catalysts are generally subjected to sulfurization in order to form the active species.

The addition of an organic compound to the hydrotreating catalysts to improve their activity has been recommended by those skilled in the art, in particular for catalysts which have been prepared by impregnation followed by drying without subsequent calcination. These catalysts are often referred to as "additive dried catalysts".

Many documents describe the use of different ranges of organic compounds as additives, such as nitrogen-containing organic compounds and/or oxygen-containing organic compounds.

In the family of organic compounds containing oxygen, the use of optionally etherified mono, di- or polyalcohols is described in documents WO96/41848, WO01/76741, US4012340, US3954673, EP601722 and WO2005/035691.

There are also several patents claiming the use of carboxylic acids (EP1402948, EP0482817). In particular, in the document EP0482817, citric acid, but also tartaric, butyric, hydroxyhexanoic, malic, gluconic, glyceric, glycolic, hydroxybutyric acids have been described. The specificity lies in the drying which must be carried out at a temperature below 200°C.

The prior art more rarely mentions additives comprising ester functions (EP1046424, WO2006/077326).

Document US2014/0353213 describes the use of lactams, cyclic esters (lactone type) or cyclic ethers (oxacycloalkane type).

Whatever the compounds chosen, the modifications induced do not always make it possible to increase the performance of the catalyst sufficiently to meet the specifications concerning the sulfur and/or nitrogen contents of the fuels. In addition, it is often very complicated to proceed with their industrial deployment as the methods are complex to implement.

Consequently, it is essential for catalyst manufacturers to find new hydrotreating and/or hydrocracking catalysts with improved performance.

Summary

The invention relates to a catalyst comprising a support based on alumina or silica or silica-alumina, at least one element from group VIII, at least one element from group VIB and at least one compound of formula (I)

in which:

- R1 is a hydrocarbon radical comprising from 1 to 12 carbon atoms, saturated or not, linear, branched or cyclic,

- X is chosen from a hydrocarbon radical comprising from 1 to 12 carbon atoms, saturated or not, linear, branched or cyclic, a hydrogen atom and an alcohol function.

The applicant has in fact observed that the use of a compound of formula (I) as an organic additive on a catalyst containing at least one element from group VIII and at least one element from group VIB, made it possible to obtain a hydrotreating and/or hydrocracking catalyst showing improved catalytic performance.

Indeed, the catalyst according to the invention shows an increased activity compared to the non-additive catalysts and to the known additived dried catalysts. Typically, thanks to the increase in activity, the temperature necessary to reach a desired sulfur or nitrogen content (for example 10 ppm of sulfur in the case of a diesel load, in ULSD or Ultra Low Sulfur Diesel mode according to the Anglo-Saxon terminology) can be lowered. Also, the stability is increased, because the cycle time is extended thanks to the necessary temperature reduction.

According to a variant, the compound of formula (I) is chosen from dimethyl tartrate, diethyl tartrate, diisopropyl tartrate, di-tert-butyl tartrate, dimethyl malate, diethyl malate, malate diisopropyl and dibutyl malate.

Alternatively, the group VIB element content is between 5 and 40% by weight expressed as group VIB metal oxide relative to the total weight of the catalyst and the group VIII element content is between 1 and 10% by weight. expressed as Group VIII metal oxide relative to the total weight of the catalyst.

According to a variant, the molar ratio of group VIII element to group VIB element in the catalyst is between 0.1 and 0.8.

According to one variant, the catalyst also contains phosphorus, the phosphorus content being between 0.1 and 20% by weight expressed as P ₂ O ₅ relative to the total weight of the catalyst and the phosphorus molar ratio to the element of the group VIB in the catalyst is greater than or equal to 0.05.

According to a variant, the content of compound of formula (I) is between 1 and 45% by weight relative to the total weight of the catalyst.

According to a variant, the catalyst also contains an organic compound other than the compound of formula (I) containing oxygen and/or nitrogen and/or sulfur.

According to this variant, the organic compound(s) is (are) chosen from a compound comprising one or more chemical functions chosen from a carboxylic, alcohol, thiol, thioether, sulphone, sulphoxide, ether, aldehyde, ketone, ester, carbonate, amine, nitrile, imide, oxime, urea, amide or even compounds including a furan ring or even sugars.

According to this variant, the organic compound other than the compound of formula (I) is chosen from γ-valerolactone, 2-acetylbutyrolactone, triethylene glycol, diethylene glycol, ethylene glycol, ethylenediaminetetraacetic acid (EDTA), l maleic acid, malonic acid, citric acid, gluconic acid, glucose, fructose, sucrose, sorbitol, xylitol, γ-ketovaleric acid, dimethylformamide, 1-methyl-2 -pyrrolidinone, propylene carbonate, 2-methoxyethyl 3-oxobutanoate, bicine, tricine, 2-furaldehyde (also known as furfural), 5-hydroxymethylfurfural (also known as 5-(hydroxymethyl )-2-furaldehyde or 5-HMF), 2-acetylfuran, 5-methyl-2-furaldehyde, ascorbic acid, butyl lactate, ethyl lactate, butyl butyryllactate, 3-hydroxybutanoate ethyl acetate, ethyl 3-ethoxypropanoate, 2-ethoxyethyl acetate, 2-butoxyethyl acetate, 2-hydroxyethyl acrylate, 1-vinyl-2-pyrrolidinone, 1,3- dimethyl-2-imidazolidinone, 1,5-pentanediol, 1-(2-hydroxyethyl)-2-pyrrolidinone, 1-(2-hydroxyethyl)-2,5-pyrrolidinedione, 5-methyl-2(3H) -furanone, 1-methyl-2-piperidinone, 4-aminobutanoic acid, butyl glycolate, ethyl 2-mercaptopropanoate, ethyl 4-oxopentanoate, diethyl maleate, dimethyl maleate, dimethyl fumarate, diethyl fumarate, dimethyl adipate and dimethyl 3-oxoglutarate.

According to a variant, the catalyst is at least partially sulfurized.

The invention also relates to processes for preparing the catalyst according to the invention as described below.

The invention also relates to the use of the catalyst according to the invention in a process for the hydrotreating and/or hydrocracking of hydrocarbon cuts.

In the following, the groups of chemical elements are given according to the CAS classification (CRC Handbook of Chemistry and Physics, publisher CRC press, editor-in-chief DR Lide, ^81st edition, 2000-2001). For example, group VIII according to the CAS classification corresponds to the metals of columns 8, 9 and 10 according to the new IUPAC classification.

By hydrotreating we mean reactions including in particular hydrodesulphurization (HDS), hydrodenitrogenation (HDN) and the hydrogenation of aromatics (HDA).

Detailed description of the invention

Catalyst

The invention relates to a catalyst comprising a support based on alumina or silica or silica-alumina, at least one element from group VIII, at least one element from group VIB and at least one organic compound of formula (I) such as described below.

The catalyst according to the invention can be a fresh catalyst, that is to say a catalyst which has not been used as a catalyst before in a catalytic unit and in particular in hydrotreating and/or hydrocracking.

The catalyst according to the invention can also be a rejuvenated catalyst. A rejuvenated catalyst is understood to mean a catalyst which has been used as a catalyst in a catalytic unit and in particular in hydrotreating and/or hydrocracking and which has been subjected to at least one stage of partial or total elimination of the coke, for example by calcination (regeneration). This regenerated catalyst is then added to at least one compound of formula (I) to obtain the rejuvenated catalyst. This rejuvenated catalyst may contain one or more other organic additive(s) which may be added before, after or at the same time as the compound of formula (I).

The hydrogenating function of said catalyst, also called active phase, is ensured by at least one element from group VIB and by at least one element from group VIII.

Preferred Group VIB elements are molybdenum and tungsten. Preferred group VIII elements are non-noble elements and in particular cobalt and nickel. Advantageously, the hydrogenating function is chosen from the group formed by combinations of the elements cobalt-molybdenum, nickel-molybdenum, nickel-tungsten or nickel-cobalt-molybdenum, or nickel-molybdenum-tungsten.

In the case where a significant activity in hydrodesulphurization, or in hydrodenitrogenation and in hydrogenation of aromatics is desired, the hydrogenating function is advantageously provided by the combination of nickel and molybdenum; a combination of nickel and tungsten in the presence of molybdenum can also be advantageous. In the case of charges of the vacuum distillate or heavier type, combinations of the cobalt-nickel-molybdenum type can be advantageously used.

The total content of group VIB and group VIII elements is advantageously greater than 6% by weight, expressed as oxide relative to the total weight of the catalyst.

The content of group VIB element is between 5 and 40% by weight, preferably between 8 and 39% by weight, and more preferably between 10 and 38% by weight expressed as group VIB metal oxide relative to the total weight of the catalyst.

The content of group VIII element is between 1 and 10% by weight, preferably between 1.5 and 9% by weight, and more preferably between 2 and 8% by weight expressed as group VIII metal oxide relative to the weight total catalyst.

The molar ratio of group VIII element to group VIB element in the catalyst is preferably between 0.1 and 0.8, preferably between 0.15 and 0.6 and even more preferably between 0.2 and 0.5.

The catalyst according to the invention advantageously also comprises phosphorus as dopant. The dopant is an added element which in itself has no catalytic character but which increases the catalytic activity of the active phase.

The phosphorus content in said catalyst is preferably between 0.1 and 20% by weight expressed as P₂O₅ relative to the total weight of the catalyst, preferably between 0.2 and 15% by weight expressed as P₂O₅, and very preferably between 0.3 and 11% by weight expressed as P₂O₅ .

The phosphorus molar ratio to the group VIB element in the catalyst is greater than or equal to 0.05, preferably greater than or equal to 0.07, preferably between 0.08 and 1, preferably between 0.1 and 0.9 and very preferably between 0.15 and 0.8.

The catalyst according to the invention, with or without phosphorus, can advantageously also contain at least one dopant chosen from boron, fluorine and a mixture of boron and fluorine.

When the catalyst contains boron or fluorine or a mixture of boron and fluorine, the content of boron or fluorine or a mixture of the two is preferably between 0.1 and 10% by weight expressed as boron oxide and/or in fluorine relative to the total weight of the catalyst, preferably between 0.2 and 7% by weight, and very preferably between 0.2 and 5% by weight.

The catalyst according to the invention comprises a support based on alumina or silica or silica-alumina.

When the support of said catalyst is based on alumina, it contains more than 50% by weight of alumina relative to the total weight of the support and, in general, it contains only alumina or silica-alumina such as defined below.

Preferably, the support comprises alumina, and preferably extruded alumina. Preferably, the alumina is gamma alumina.

The alumina support advantageously has a total pore volume of between 0.1 and 1.5 cm ³ .g ^-1 , preferably between 0.4 and 1.1 cm ³ .g ^-1 . The total porous volume is measured by mercury porosimetry according to the ASTM D4284 standard with a wetting angle of 140°, as described in the work Rouquerol F.; Rouquerol J.; Singh K. “Adsorption by Powders & Porous Solids: Principle, methodology and applications”, Academic Press, 1999, for example by means of an Autopore III™ model apparatus from the Micromeritics™ brand.

The specific surface of the alumina support is advantageously between 5 and 400 m ² .g ^-1 , preferably between 10 and 350 m ² .g ^-1 , more preferably between 40 and 350 m ² .g ^{-1 .} . The specific surface is determined in the present invention by the BET method according to standard ASTM D3663, method described in the same work cited above.

In another preferred case, the support of said catalyst is a silica-alumina containing at least 50% by weight of alumina relative to the total weight of the support. The silica content in the support is at most 50% by weight relative to the total weight of the support, usually less than or equal to 45% by weight, preferably less than or equal to 40%.

Silicon sources are well known to those skilled in the art. Mention may be made, by way of example, of silicic acid, silica in powder form or in colloidal form (silica sol), tetraethylorthosilicate Si(OEt) ₄ .

When the support of said catalyst is based on silica, it contains more than 50% by weight of silica relative to the total weight of the support and, in general, it contains only silica.

According to a particularly preferred variant, the support consists of alumina, silica or silica-alumina.

The support may also advantageously also contain from 0.1 to 50% weight of zeolite relative to the total weight of the support. In this case, all the sources of zeolite and all the methods of associated preparations known to those skilled in the art can be incorporated. Preferably, the zeolite is chosen from the group FAU, BEA, ISV, IWR, IWW, MEI, UWY and preferably, the zeolite is chosen from the group FAU and BEA, such as Y and/or beta zeolite, and particularly preferably such as USY and/or beta zeolite.

The support may also contain at least a part of metal(s) VIB and VIII, and/or at least a part of dopant(s) including phosphorus and/or at least a part of organic compound(s) containing oxygen (the compound of formula (I) or other) and/or nitrogen and/or sulfur which have been introduced outside the impregnations (introduced for example during substrate preparation).

The support is advantageously in the form of beads, extrudates, pellets or irregular and non-spherical agglomerates, the specific shape of which may result from a crushing step.

The catalyst according to the invention also comprises at least one compound of formula (I)

in which:

- R1 is a hydrocarbon radical comprising from 1 to 12 carbon atoms, saturated or not, linear, branched or cyclic,

- X is chosen from a hydrocarbon radical comprising from 1 to 12 carbon atoms, saturated or not, linear, branched or cyclic, a hydrogen atom and an alcohol function.

Preferably, X is chosen from a hydrogen atom and an alcohol function.

Preferably, the compound of formula (I) is chosen from dimethyl tartrate, diethyl tartrate, diisopropyl tartrate, di-tert-butyl tartrate, dimethyl malate, diethyl malate, diethyl malate, diisopropyl and dibutyl malate.

More preferably, the compound of formula (I) is chosen from dimethyl tartrate, diethyl tartrate and diethyl malate.

The presence of at least one compound of formula (I) on the catalyst makes it possible to observe an increased activity compared to the catalysts without additives and to the known additived dried catalysts. The catalyst may comprise one or more compounds of formula (I), in particular two compounds of formula (I). The content of compound(s) of formula (I) on the catalyst according to the invention is between 1 and 45% by weight, preferably between 2 and 30% by weight, and more preferably between 3 and 25% by weight relative to the total weight of the catalyst. During the preparation of the catalyst requiring a drying step, the drying step(s) consecutive to the introduction of the compound of formula (I) is (are) carried out at a temperature below 200° C. so as to preferably retain at least 30%, preferably at least 50%, and very preferably at least 70% of the quantity of the compound of formula (I) introduced, calculated on the basis of the carbon remaining on the catalyst. The remaining carbon is measured by elemental analysis according to ASTM D5373.

The compound of formula (I) can come from the traditional chemical industry with generally high purities, for example greater than 99%. It can also have a lower purity. In this case, its purity may be between 80 and 99%, preferably between 85 and 95%.

The catalyst according to the invention may comprise, in addition to the compound of formula (I), another organic compound or a group of organic compounds known for their role as additives.

The function of additives is to increase the catalytic activity compared to non-additive catalysts. More particularly, the catalyst according to the invention may also comprise one or more organic compounds containing oxygen other than the compound of formula (I) and/or one or more organic compounds containing nitrogen and/or one or more several organic compounds containing sulfur. Preferably, the catalyst according to the invention may also comprise one or more organic compounds containing oxygen other than the compound of formula (I) and/or one or more organic compounds containing nitrogen. Preferably, the organic compound contains at least 2 carbon atoms and at least one oxygen and/or nitrogen atom.

Generally, the organic compound is chosen from a compound comprising one or more chemical functions chosen from a carboxylic function, alcohol, thiol, thioether, sulphone, sulphoxide, ether, aldehyde, ketone, ester, carbonate, amine, nitrile, imide, oxime, urea and amide or also compounds including a furan ring or alternatively sugars.

The organic compound containing oxygen can be one or more chosen from compounds comprising one or more chemical functions chosen from a carboxylic, alcohol, ether, aldehyde, ketone, ester or carbonate function or else compounds including a furan cycle. or sugars. By way of example, the organic compound containing oxygen can be one or more chosen from the group consisting of ethylene glycol, diethylene glycol, triethylene glycol, a polyethylene glycol (with a molecular weight of between 200 and 1500 g /mol), propylene glycol, 2-butoxyethanol, 2-(2-butoxyethoxy)ethanol, 2-(2-methoxyethoxy)ethanol, triethyleneglycoldimethylether, glycerol, acetophenone, 2,4-pentanedione, pentanone, acetic acid, maleic acid, malic acid, malonic acid, oxalic acid, gluconic acid, tartaric acid, citric acid, γ-ketovaleric acid, a succinate of C1-C4 dialkyl and more particularly dimethyl succinate, methyl acetoacetate, ethyl acetoacetate, 2-methoxyethyl 3-oxobutanoate, 2-methacryloyloxyethyl 3-oxobutanoate, dibenzofuran, a crown ether, orthophthalic acid, glucose, fructose, sucrose, sorbitol, xylitol, γ-valerolactone, 2-acetylbutyrolactone, propylene carbonate, 2-furaldehyde (also known as furfural), 5 -hydroxymethylfurfural (also known as 5-(hydroxymethyl)-2-furaldehyde or 5-HMF), 2-acetylfuran, 5-methyl-2-furaldehyde, methyl 2-furoate, furfuryl alcohol (also known as furfuranol), furfuryl acetate, ascorbic acid, butyl lactate, ethyl lactate, butyl butyryllactate, ethyl 3-hydroxybutanoate, ethyl 3-ethoxypropanoate, methyl 3-methoxypropanoate, 2-ethoxyethyl acetate, 2-butoxyethyl acetate, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 1,5-pentanediol, 3-methyl-1 ,5-pentanediol, 1,5-hexanediol, 3-ethyl-1,5-pentanediol, 2,4-diethyl-1,5-pentanediol, 5-methyl-2(3H)-furanone, glycolate ethyl 4-oxo-pentanoate, diethyl maleate, dimethyl maleate, dimethyl fumarate, diethyl fumarate, dimethyl adipate and dimethyl 3-oxoglutarate.

The organic compound containing nitrogen can be one or more chosen from compounds comprising one or more chemical functions chosen from an amine or nitrile function. By way of example, the organic compound containing nitrogen can be one or more selected from the group consisting of ethylenediamine, diethylenetriamine, hexamethylenediamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, acetonitrile , octylamine, guanidine or a carbazole.

The organic compound containing oxygen and nitrogen can be one or more chosen from compounds comprising one or more chemical functions chosen from a carboxylic acid, alcohol, ether, aldehyde, ketone, ester, carbonate, amine, nitrile, imide, amide, urea or oxime. By way of example, the organic compound containing oxygen and nitrogen can be one or more chosen from the group consisting of 1,2-cyclohexanediaminetetraacetic acid, monoethanolamine (MEA), 1- methyl-2-pyrrolidinone, dimethylformamide, ethylenediaminetetraacetic acid (EDTA), alanine, glycine, nitrilotriacetic acid (NTA), N-(2-hydroxyethyl)ethylenediamine-N,N′,N acid ′-triacetic acid (HEDTA), diethylene-triaminepentaacetic acid (DTPA), tetramethylurea, glutamic acid, dimethylglyoxime, bicine, tricine, 2-methoxyethyl cyanoacetate, 1-ethyl-2-pyrrolidinone, 1-vinyl-2-pyrrolidinone, 1,3-dimethyl-2-imidazolidinone, 1-(2-hydroxyethyl)-2-pyrrolidinone, 1-(2-hydroxyethyl)-2,5-pyrrolidinedione, 1 -methyl-2-piperidinone, 1-acetyl-2-azepanone, 1-vinyl-2-azepanone and 4-aminobutanoic acid.

The organic compound containing sulfur can be one or more chosen from compounds comprising one or more chemical functions chosen from a thiol, thioether, sulphone or sulphoxide function. By way of example, the organic compound containing sulfur can be one or more selected from the group consisting of thioglycolic acid, 2,2'-thiodiethanol, 2-hydroxy-4-methylthiobutanoic acid, a sulfonated derivative of a benzothiophene or a sulfoxide derivative of a benzothiophene, ethyl 2-mercaptopropanoate, methyl 3-(methylthio)propanoate and ethyl 3-(methylthio)propanoate.

Preferably, the organic compound contains oxygen, preferably it is chosen from γ-valerolactone, 2-acetylbutyrolactone, triethylene glycol, diethylene glycol, ethylene glycol, ethylenediaminetetraacetic acid (EDTA), l maleic acid, malonic acid, citric acid, gluconic acid, glucose, fructose, sucrose, sorbitol, xylitol, γ-ketovaleric acid, dimethylformamide, 1-methyl-2 -pyrrolidinone, propylene carbonate, 2-methoxyethyl 3-oxobutanoate, bicine, tricine, 2-furaldehyde (also known as furfural), 5-hydroxymethylfurfural (also known as 5-(hydroxymethyl )-2-furaldehyde or 5-HMF), 2-acetylfuran, 5-methyl-2-furaldehyde, ascorbic acid, butyl lactate, ethyl lactate, butyl butyryllactate, 3-hydroxybutanoate ethyl acetate, ethyl 3-ethoxypropanoate, 2-ethoxyethyl acetate, 2-butoxyethyl acetate, 2-hydroxyethyl acrylate, 1-vinyl-2-pyrrolidinone, 1,3- dimethyl-2-imidazolidinone, 1,5-pentanediol, 1-(2-hydroxyethyl)-2-pyrrolidinone, 1-(2-hydroxyethyl)-2,5-pyrrolidinedione, 5-methyl-2(3H)- furanone, 1-methyl-2-piperidinone, 4-aminobutanoic acid, butyl glycolate, ethyl 2-mercaptopropanoate, ethyl 4-oxopentanoate, diethyl maleate, dimethyl maleate, dimethyl fumarate, diethyl fumarate, dimethyl adipate and dimethyl 3-oxoglutarate.

When they are present, the content of organic compound(s) with additive function(s) containing oxygen (other than the compound of formula (I)) and/or nitrogen and/or sulfur on the catalyst according to the invention is between 1 and 30% by weight, preferably between 1.5 and 25% by weight, and more preferably between 2 and 20% by weight relative to the total weight of the catalyst.

Preparation process

The catalyst according to the invention can be prepared according to any mode of preparation of a supported catalyst to which an organic compound is known to those skilled in the art.

The catalyst according to the invention can be prepared by implementing a step of impregnating said compound of formula (I), advantageously using a solution containing a solvent in which the compound of formula (I) is diluted. According to this variant, the process for preparing said catalyst implements a step of adding said compound of formula (I) via the liquid phase. After impregnation, a drying step is then necessary to eliminate the solvent and/or the excess of the compound of formula (I) and thus release the porosity necessary for the implementation of the catalyst.

The catalyst according to the invention can be prepared according to a preparation process comprising the following steps:

a) at least one compound comprising an element from group VIB, at least one compound comprising an element from group VIII, at least one compound of formula (I) and optionally phosphorus is brought into contact with an alumina-based support or silica or silica-alumina, or a regenerated catalyst containing a support based on alumina or silica or silica-alumina, at least one element from group VIB, at least one element from group VIII and optionally phosphorus, with at least one compound of formula (I), so as to obtain a catalyst precursor,

b) said catalyst precursor resulting from step a) is dried at a temperature below 200° C., without subsequently calcining it.

According to this variant, the process for preparing a fresh catalyst will be described first, then the process for preparing a rejuvenated catalyst.

I) Process for preparing a fresh catalyst

Step a) of bringing into contact comprises several modes of implementation which are distinguished in particular by the moment of introduction of the compound of formula (I) which can be carried out either at the same time as the impregnation of the metals (co -impregnation), either after the impregnation of the metals (post-impregnation), or finally before the impregnation of the metals (pre-impregnation). In addition, the contacting step can combine at least two modes of implementation, for example co-impregnation and post-impregnation. These different modes of implementation will be described below. Each mode, taken alone or in combination, can take place in one or more stages.

It is important to emphasize that the catalyst according to the invention during its preparation process does not undergo calcination after the introduction of the compound of formula (I) or any other organic compound containing oxygen and / or nitrogen and/or sulfur in order to at least partially preserve the compound of formula (I) or any other organic compound in the catalyst. Here, calcination means a heat treatment under a gas containing air or oxygen at a temperature greater than or equal to 200°C.

However, the catalyst precursor can undergo a calcination step before the introduction of the compound of formula (I) or any other organic compound containing oxygen and/or nitrogen and/or sulfur, in particular after the impregnation of the elements of group VIB and VIII (post-impregnation) optionally in the presence of phosphorus and/or of another dopant or during regeneration of a catalyst already used. The hydrogenating function comprising the elements of group VIB and of group VIII of the catalyst according to the invention, also called active phase, is then in an oxide form.

According to another variant, the catalyst precursor does not undergo a calcination step after the impregnation of the elements of group VIB and VIII (post-impregnation), it is simply dried. The hydrogenating function comprising the elements of group VIB and of group VIII of the catalyst according to the invention, also called active phase, is then not in an oxide form.

Whatever the mode of implementation, step a) of bringing into contact generally comprises at least one impregnation step, preferably a dry impregnation step, in which the support is impregnated with a solution of impregnation comprising at least one element from group VIB, at least one element from group VIII, and optionally phosphorus. In the case of the co-impregnation described below in detail, this impregnation solution further comprises at least one compound of formula (I). The elements of group VIB and of group VIII are generally introduced by impregnation, preferably by dry impregnation or by impregnation in excess of solution. Preferably, all of the elements of group VIB and of group VIII are introduced by impregnation, preferably by dry impregnation, regardless of the mode of implementation.

The elements of group VIB and of group VIII can also be introduced in part during the shaping of said support at the time of mixing with at least one alumina gel chosen as matrix, the rest of the hydrogenating elements then being introduced subsequently by impregnation . Preferably, when the elements of group VIB and of group VIII are partly introduced at the time of mixing, the proportion of element of group VIB introduced during this step is less than 5% by weight of the total quantity of element of group VIB introduced on the final catalyst.

Preferably, the element from group VIB is introduced at the same time as the element from group VIII, whatever the mode of introduction.

The molybdenum precursors which can be used are well known to those skilled in the art. For example, among the sources of molybdenum, it is possible to use oxides and hydroxides, molybdic acids and their salts, in particular ammonium salts such as ammonium molybdate, ammonium heptamolybdate, phosphomolybdic acid ( H ₃ PMo ₁₂ O ₄₀ ) and their salts, and optionally silicomolybdic acid (H ₄ SiMo ₁₂ O ₄₀ ) and its salts. The sources of molybdenum can also be heteropolycompounds of Keggin, lacunary Keggin, substituted Keggin, Dawson, Anderson, Strandberg type, for example. Preferably, molybdenum trioxide and heteropolyanions of the Strandberg, Keggin, lacunary Keggin or substituted Keggin type are used.

The tungsten precursors which can be used are also well known to those skilled in the art. For example, among the sources of tungsten, it is possible to use oxides and hydroxides, tungstic acids and their salts, in particular ammonium salts such as ammonium tungstate, ammonium metatungstate, phosphotungstic acid and their salts, and optionally silicotungstic acid (H ₄ SiW ₁₂ O ₄₀ ) and its salts. The sources of tungsten can also be heteropolycompounds of Keggin, lacunary Keggin, substituted Keggin, Dawson type, for example. Preferably, ammonium oxides and salts are used, such as ammonium metatungstate or heteropolyanions of Keggin, lacunary Keggin or substituted Keggin type.

The precursors of the elements of group VIII which can be used are advantageously chosen from oxides, hydroxides, hydroxycarbonates, carbonates and nitrates of the elements of group VIII, for example, nickel hydroxycarbonate, carbonate or hydroxide of cobalt are preferably used.

Phosphorus, when present, can be introduced in whole or in part by impregnation. Preferably, it is introduced by impregnation, preferably dry, using a solution containing the precursors of the elements of group VIB and of group VIII.

Said phosphorus can advantageously be introduced alone or in a mixture with at least one of the elements of group VIB and of group VIII, and this during any of the steps of impregnation of the hydrogenating function if the latter is introduced. several times. Said phosphorus can also be introduced, in whole or in part, during the impregnation of the compound of formula (I) if the latter is introduced separately from the hydrogenating function (case of the post- and pre-impregnation described later) and this in presence or absence of an organic compound other than the compound of formula (I) containing oxygen and/or nitrogen and/or sulphur. It can also be introduced during the synthesis of the support, at any stage of its synthesis. It can thus be introduced before, during or after the mixing of the chosen alumina gel matrix, such as for example and preferably aluminum oxyhydroxide (boehmite) precursor of alumina.

The preferred phosphorus precursor is orthophosphoric acid H ₃ PO ₄ , but its salts and esters such as ammonium phosphates are also suitable. The phosphorus can also be introduced at the same time as the element(s) of group VIB in the form of heteropolyanions of Keggin, lacunary Keggin, substituted Keggin or of the Strandberg type.

The compound(s) of formula (I) is (are) advantageously introduced into an impregnation solution which, depending on the method of preparation, may be the same solution or a different solution from that containing the elements of group VIB and VIII, in an amount corresponding to:

- at a molar ratio of the compound of formula (I) per element(s) of group VIB of the catalyst precursor of between 0.01 and 5 mol/mol, preferably between 0.05 and 3 mol/mol, so preferably between 0.05 and 1.5 mol/mol and very preferably between 0.1 and 1 mol/mol, calculated on the basis of the components introduced into the impregnation solution(s), and

- at a molar ratio of the compound of formula (I) per element(s) of group VIII of the catalyst precursor of between 0.02 and 17 mol/mol, preferably between 0.1 and 10 mol/mol, so preferably between 0.15 and 5 mol/mol and very preferably between 0.6 and 3.5 mol/mol, calculated on the basis of the components introduced into the impregnation solution(s).

When several compounds of formula (I) are present, the different molar ratios apply for each of the compounds of formula (I) present.

Any impregnation solution described in the present invention can comprise any polar solvent known to those skilled in the art. Said polar solvent used is advantageously chosen from the group formed by methanol, ethanol, water, phenol, cyclohexanol, taken alone or as a mixture. Said polar solvent can also advantageously be chosen from the group formed by propylene carbonate, DMSO (dimethylsulfoxide), N-methylpyrrolidone (NMP) or sulfolane, taken alone or as a mixture. Preferably, a polar protic solvent is used. A list of the usual polar solvents as well as their dielectric constant can be found in the book “Solvents and Solvent Effects in Organic Chemistry”, C. Reichardt, Wiley-VCH, 3rd edition, 2003, pages 472-474. Very preferably, the solvent used is water or ethanol, and particularly preferably, the solvent is water. In one possible embodiment, the solvent may be absent in the impregnation solution, in particular during a pre- or post-impregnation preparation.

When the catalyst further comprises a dopant selected from boron, fluorine or a mixture of boron and fluorine, the introduction of this (these) dopant(s) can be done in the same way as the introduction of phosphorus described above at various stages of preparation and in various ways.

The boron precursors can be boric acid, orthoboric acid H ₃ BO ₃ , ammonium biborate or pentaborate, boron oxide, boric esters. The boron can be introduced for example by a solution of boric acid in a water/alcohol mixture or else in a water/ethanolamine mixture. Preferably the boron precursor, if boron is introduced, is orthoboric acid.

The fluorine precursors which can be used are well known to those skilled in the art. For example, the 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 reaction between the organic compound and hydrofluoric acid. The fluorine can be introduced, for example, by impregnation with an aqueous solution of hydrofluoric acid, or of ammonium fluoride or else of ammonium bifluoride.

When the catalyst further comprises an additional additive (in addition to the compound of formula (I)) or a group of additional additives chosen from an organic compound other than the compound of formula (I) containing oxygen and/or nitrogen and/or sulfur, the latter can be introduced into the impregnation solution of step a).

The molar ratio of organic compound(s) containing oxygen and/or nitrogen and/or sulfur per element(s) of group VIB on the catalyst is between 0.05 and 5 mol/ mol, preferably between 0.1 and 4 mol/mol, preferably between 0.2 and 3 mol/mol, calculated on the basis of the components introduced into the impregnation solution(s).

The molar ratio of organic compound(s) containing oxygen and/or nitrogen and/or sulfur per compound of formula (I) is between 0.05 and 5 mol/mol, preferably between 0.1 and 4 mol/mol, preferably between 0.2 and 3 mol/mol, calculated on the basis of the components introduced into the impregnation solution(s).

When several organic compounds containing oxygen and/or nitrogen and/or sulfur are present, the different molar ratios apply for each of the organic compounds present.

Advantageously, after each impregnation step, the impregnated support is allowed to mature. Curing allows the impregnation solution to disperse evenly within the support.

Any maturation step described in the present invention is advantageously carried out at atmospheric pressure, in an atmosphere saturated with water and at a temperature between 17° C. and 50° C., and preferably at room temperature. Generally, a maturation period of between ten minutes and forty-eight hours, and preferably between thirty minutes and five hours, is sufficient. Longer durations are not excluded, but do not necessarily bring improvement.

In accordance with step b) of the preparation process according to the invention, the catalyst precursor obtained in step a), optionally matured, is subjected to a drying step at a temperature below 200° C. without a subsequent calcination step.

Any drying step subsequent to the introduction of the compound of formula (I) described in the present invention is carried out at a lower temperature
at 200°C, preferably between 50 and 180°C, preferably between 70 and 150°C and very preferably between 75 and 130°C.

The drying step is advantageously carried out by any technique known to those skilled in the art. It is advantageously carried out at atmospheric pressure or at reduced pressure, and preferably at atmospheric pressure. It is advantageously carried out in a traversed bed using air or any other hot gas. Preferably, when the drying is carried out in a fixed bed, the gas used is either air or an inert gas such as argon or nitrogen. Very preferably, the drying is carried out in a traversed bed in the presence of nitrogen and/or air. Preferably, the drying step has a short duration of between 5 minutes and 4 hours, preferably between 30 minutes and 4 hours and very preferably between 1 hour and 3 hours. The drying is then carried out so as to preferably retain at least 30% of the compound of formula (I) introduced during an impregnation step, preferably this quantity is greater than 50% and even more preferably, greater than 70 %, calculated on the basis of the carbon remaining on the catalyst. When an organic compound other than the compound of formula (I) containing oxygen and/or nitrogen and/or sulfur is present, the drying step is carried out so as to preferably retain at least 30 %, preferably at least 50%, and very preferably at least 70% of the quantity introduced calculated on the basis of the carbon remaining on the catalyst.

At the end of the drying step b), a dried catalyst is obtained, which is not subjected to any subsequent calcination step.

Co-impregnation

According to a first embodiment of step a) of the process for preparing the catalyst (fresh), said compounds are deposited comprising the elements of group VIB, of group VIII, of the compound of formula (I) and optionally phosphorus on said support, by one or more co-impregnation steps, that is to say that said compounds comprising the elements of group VIB, of group VIII, the compound of formula (I) and optionally phosphorus are introduced simultaneously in said support (“co-impregnation”).

Post-impregnation

According to a second embodiment of step a) of the process for preparing the (fresh) catalyst according to the invention, at least one compound of formula (I) is brought into contact with a dried and optionally calcined impregnated support comprising at least one element from group VIB, at least one element from group VIII and optionally phosphorus, said support being based on alumina or silica or silica-alumina, so as to obtain a catalyst precursor.

This second embodiment is a preparation by "post-impregnation" of the compound of formula (I).

The introduction of the elements of group VIB and of group VIII and optionally phosphorus on the support can be advantageously carried out by one or more impregnations in excess of solution on the support, or preferably by one or more dry impregnations, and, preferably, by a single dry impregnation of said support, using solution(s), preferably aqueous, containing the metal precursor(s) and preferably the phosphorus precursor.

When performing several impregnation steps, each impregnation step is preferably followed by an intermediate drying step at a temperature below 200°C. Each intermediate drying step, prior to the introduction of the compound of formula (I) can be followed by a calcination step. The calcination is generally carried out at a temperature between 200°C and 900°C, preferably between 250°C and 750°C. The calcining time is generally between 0.5 hour and 16 hours, preferably between 1 hour and 5 hours. It is generally carried out under air. Calcination transforms the precursors of group VIB and VIII metals into oxides.

The compound of formula (I) can then advantageously be deposited in one or more stages either by impregnation in excess, or by dry impregnation, or by any other means known to those skilled in the art. Preferably, the compound of formula (I) is introduced by dry impregnation, in the presence or absence of a solvent as described above.

Preferably, the solvent in the impregnation solution is water, which facilitates implementation on an industrial scale.

The catalyst precursor which has been optionally matured is then subjected to a drying step at a temperature below 200° C. without a subsequent calcination step, as described above.

Pre-impregnation

According to a third embodiment of step a) of the process for preparing the (fresh) catalyst according to the invention, at least one compound comprising an element from group VIB is brought into contact, at least one compound comprising an element of group VIII, optionally phosphorus with the support based on alumina or silica or silica-alumina which contains at least one compound of formula (I) so as to obtain a catalyst precursor.

This third embodiment is a preparation by "pre-impregnation" of the compound of formula (I).

The compound of formula (I) can be introduced at any time during the preparation of the support, and preferably during shaping or by impregnation on an already formed support.

If the introduction of the compound of formula (I) is chosen on the previously shaped support, then this can be carried out as indicated for post-impregnation.

If the introduction during shaping is chosen, said shaping is preferably carried out by extrusion kneading, by pelleting, by the drop coagulation method (oil-drop according to the Anglo-Saxon terminology), by granulation on a turntable or by any other method well known to those skilled in the art. Very preferably, said shaping is carried out by extrusion mixing, it being possible for the compound of formula (I) to be introduced at any time during the extrusion mixing. The formed material obtained at the end of the shaping step then advantageously undergoes a heat treatment step at a temperature such that at least part of the compound of formula (I) remains present, preferably at a lower temperature at 200°C.

The introduction of the elements of group VIB and of group VIII and optionally phosphorus can then advantageously be carried out by one or more impregnations.

The three methods described above can be implemented alone as described or combined to give rise to other hybrid preparation methods depending on the technical and practical constraints.

According to another alternative embodiment, the bringing into contact according to step a) combines at least two modes of bringing into contact, for example the co-impregnation of the elements of group VIB and of group VIII and optionally of phosphorus with a compound organic compound, followed by drying at a temperature below 200°C, then by post-impregnation with an organic compound which may be identical to or different from that used for the co-impregnation, given that at least one organic compounds is a compound of formula (I).

II) Process for the preparation of a rejuvenated catalyst

The catalyst according to the invention can be a rejuvenated catalyst. Its preparation process includes the following steps:

a) a regenerated catalyst containing a support based on alumina or silica or silica-alumina, at least one element from group VIB, at least one element from group VIII and optionally phosphorus, is brought into contact with at least one compound of formula (I) so as to obtain a catalyst precursor,

b) said catalyst precursor resulting from step a) is dried at a temperature below 200° C., without subsequently calcining it.

The regenerated catalyst is a catalyst which has been used as a catalyst in a catalytic unit and in particular in hydrotreating and/or hydrocracking and which has been subjected to at least one stage of partial or total elimination of coke, for example by calcination (regeneration ). The regeneration can be carried out by any means known to those skilled in the art. Regeneration is generally carried out by calcination at temperatures between 350 and 550°C, and most often between 400 and 520°C, or between 420 and 520°C, or even between 450 and 520°C, lower temperatures at 500° C. being often advantageous.

The regenerated catalyst contains a support based on alumina or silica or silica-alumina, at least one element from group VIB, at least one element from group VIII and optionally phosphorus in the respective proportions indicated above. Following regeneration, the hydrogenating function comprising the elements of group VIB and of group VIII of the regenerated catalyst is in an oxide form. It may also contain other dopants than phosphorus, as described above.

Preferably, the contacting of step a) is carried out by impregnation of the regenerated catalyst with an impregnation solution comprising at least one compound of formula (I) so as to obtain a catalyst precursor.

The compound of formula (I) can advantageously be deposited in one or more stages either by impregnation in excess, or by dry impregnation, or by any other means known to those skilled in the art in the same way as described above and with the molar ratios per Group VIB or Group VIII element described above.

The operating conditions described above concerning maturation and drying are of course applicable in the context of this latter embodiment.

sulfidation

Before its use for the hydrotreating and/or hydrocracking reaction, it is advantageous to convert the catalyst obtained according to any of the introduction methods described in the present invention into a sulphide catalyst in order to form its active species. This activation or sulfurization step is carried out by methods well known to those skilled in the art, and advantageously under a sulfo-reducing atmosphere in the presence of hydrogen and hydrogen sulfide.

At the end of step b) according to the different preparation methods of the process according to the invention, said catalyst obtained is therefore advantageously subjected to a sulfurization step, without an intermediate calcination step.

Said dried catalyst is advantageously sulfurized ex situ or in situ . Sulfurizing agents are H ₂ S gas, elemental sulphur, CS ₂ , mercaptans, sulphides and/or polysulphides, hydrocarbon cuts with a boiling point below 400°C containing sulfur compounds or any other compound containing sulfur used for the activation of the hydrocarbon charges in order to sulfurize the catalyst. Said compounds containing sulfur are advantageously chosen from alkyl disulphides such as for example dimethyl disulphide (DMDS), alkyl sulphides, such as for example dimethyl sulphide, thiols such as for example n- butyl mercaptan (or 1-butanethiol) and polysulphide compounds of the tertiononylpolysulphide type. The catalyst can also be sulfurized by the sulfur contained in the charge to be desulfurized. Preferably, the catalyst is sulfurized in situ in the presence of a sulfurizing agent and a hydrocarbon charge. Very preferably, the catalyst is sulfurized in situ in the presence of a hydrocarbon feed containing dimethyl disulfide.

Hydrotreating and/or hydrocracking process

Finally, another object of the invention is the use of the catalyst according to the invention or prepared according to the preparation process according to the invention in processes for the hydrotreating and/or hydrocracking of hydrocarbon cuts.

The catalyst according to the invention and having preferably previously undergone a sulfurization step is advantageously used for hydrotreating and/or hydrocracking reactions of hydrocarbon feedstocks such as petroleum cuts, cuts from coal or hydrocarbons produced at from natural gas, optionally in mixtures or also from a hydrocarbon fraction derived from biomass and more particularly for hydrogenation, hydrodenitrogenation, hydrodearomatization, hydrodesulfurization, hydrodeoxygenation, hydrodemetallization reactions or hydroconversion of hydrocarbon feedstocks.

In these uses, the catalyst according to the invention and having preferably previously undergone a sulfurization step has improved activity compared to the catalysts of the prior art. This catalyst can also advantageously be used during the pretreatment of catalytic cracking or hydrocracking feeds, or the hydrodesulfurization of residues or the extensive hydrodesulfurization of gas oils (ULSD Ultra Low Sulfur Diesel according to the Anglo-Saxon terminology).

The feedstocks used in the hydrotreating process are, for example, gasolines, gas oils, vacuum gas oils, atmospheric residues, vacuum residues, atmospheric distillates, vacuum distillates, heavy fuel oils, oils, waxes and paraffins, waste oils, residues or deasphalted crudes, fillers from thermal or catalytic conversion processes, lignocellulosic fillers or more generally fillers from biomass such as vegetable oils, taken alone or in a mixture. The fillers which are treated, and in particular those cited above, generally contain heteroatoms such as sulphur, oxygen and nitrogen and, for heavy fillers, they most often also contain metals.

The operating conditions used in the processes implementing the hydrocarbon feedstock hydrotreating reactions described above are generally as follows: the temperature is advantageously between 180 and 450° C., and preferably between 250 and 440° C., the pressure is advantageously between 0.5 and 30 MPa, and preferably between 1 and 18 MPa, the hourly volume velocity is advantageously between 0.1 and 20 h ^-1 and preferably between 0.2 and 5 h ^-1 , and the hydrogen/feed ratio expressed as volume of hydrogen, measured under normal temperature and pressure conditions, per volume of liquid feed is advantageously between 50 l/l to 5000 l/l and preferably 80 to 2000 l/l.

According to a first mode of use, said hydrotreating process according to the invention is a hydrotreating process, and in particular hydrodesulphurization (HDS) of a diesel fraction carried out in the presence of at least one catalyst according to the invention. . Said hydrotreating process according to the invention aims to eliminate the sulfur compounds present in said gas oil cut so as to achieve the environmental standards in force, namely an authorized sulfur content of up to 10 ppm. It also makes it possible to reduce the aromatic and nitrogen contents of the gas oil cut to be hydrotreated.

Said gas oil cut to be hydrotreated according to the process of the invention contains from 0.02 to 5.0% by weight of sulphur. It is advantageously derived from direct distillation (or straight run gas oil according to Anglo-Saxon terminology), from a coking unit (coking according to Anglo-Saxon terminology), from a visbreaking unit (visbreaking according to Anglo-Saxon terminology). Saxon), a steam cracking unit (steam cracking according to the Anglo-Saxon terminology), a hydrotreating and/or hydrocracking unit for heavier loads and/or a catalytic cracking unit (Fluid Catalytic Cracking according to Anglo-Saxon terminology). Said diesel fraction preferably has at least 90% of the compounds whose boiling point is between 250° C. and 400° C. at atmospheric pressure.

The process for hydrotreating said gas oil cut according to the invention is implemented under the following operating conditions: a temperature of between 200 and 400° C., preferably between 300 and 380° C., a total pressure of between 2 MPa and 10 MPa and more preferably between 3 MPa and 8 MPa with a ratio of volume of hydrogen per volume of hydrocarbon charge, expressed in volume of hydrogen, measured under normal temperature and pressure conditions, per volume of liquid charge, of between 100 and 600 liters per liter and more preferentially between 200 and 400 liters per liter and an hourly volume velocity (VVH) of between 1 and 10 h ^-1 , preferentially between 2 and
8:00 ^a.m. The VVH corresponds to the inverse of the contact time expressed in hours and is defined by the ratio of the volume flow rate of liquid hydrocarbon feedstock to the volume of catalyst loaded into the reaction unit implementing the hydrotreatment process according to the invention. . The reaction unit implementing the process for hydrotreating said diesel fraction according to the invention is preferably operated in a fixed bed, in a moving bed or in an ebullated bed, preferably in a fixed bed.

According to a second mode of use, said hydrotreating and/or hydrocracking process according to the invention is a hydrotreating process (in particular hydrodesulfurization, hydrodeazoation, hydrogenation of aromatics) and/or hydrocracking of a cut of vacuum distillate produced in the presence of at least one catalyst according to the invention. Said hydrotreating and/or hydrocracking process, otherwise called hydrocracking or hydrocracking pretreatment process according to the invention, aims, depending on the case, at eliminating the sulfur, nitrogen or aromatic compounds present in said distillate cut so as to carry out a pretreatment before conversion in catalytic cracking or hydroconversion processes, or to hydrocrack the distillate cut which may have been pretreated beforehand if necessary.

A wide variety of feedstocks can be processed by the vacuum distillate hydrotreating and/or hydrocracking processes described above. Generally they contain at least 20% volume and often at least 80% volume of compounds boiling above 340° C. at atmospheric pressure. The feedstock can be, for example, vacuum distillates as well as feedstocks from aromatics extraction units from lubricating oil bases or from solvent dewaxing of lubricating oil bases, and/or deasphalted oils. , or else the filler can be a deasphalted oil or paraffins resulting from the Fischer-Tropsch process or even any mixture of the aforementioned fillers. In general, the fillers have a boiling point T5 greater than 340°C at atmospheric pressure, and better still greater than 370°C at atmospheric pressure, that is to say that 95% of the compounds present in the filler have a point boiling point higher than 340°C, and better still higher than 370°C. The nitrogen content of the feeds treated in the processes according to the invention is usually greater than 200 ppm by weight, preferably between 500 and 10,000 ppm by weight. The sulfur content of the feeds treated in the processes according to the invention is usually between 0.01 and 5.0% by weight. The filler may optionally contain metals (for example nickel and vanadium). The asphaltene content is generally less than 3000 ppm by weight.

The hydrotreating and/or hydrocracking catalyst is generally brought into contact, in the presence of hydrogen, with the feeds described above, at a temperature above 200° C., often between 250° C. and 480° C., advantageously between 320°C and 450°C, preferably between 330°C and 435°C, under a pressure greater than 1 MPa, often between 2 and 25 MPa, preferably between 3 and 20 MPa, the volumetric speed being between 0 ,1 and 20.0 h ^-1 and preferably 0.1-6.0 h ^-1 , preferably 0.2-3.0 h ^-1 , and the amount of hydrogen introduced is such that the volume ratio liter of hydrogen/liter of hydrocarbon, expressed in volume of hydrogen, measured under normal conditions of temperature and pressure, per volume of liquid charge, i.e. between 80 and 5,000 l/l and most often between 100 and 2000 l/l. These operating conditions used in the processes according to the invention generally make it possible to achieve conversions per pass, into products having boiling points below 340° C. at atmospheric pressure, and better still below 370° C. at atmospheric pressure, above to 15% and even more preferably between 20 and 95%.

The vacuum distillate hydrotreating and/or hydrocracking processes using the catalysts according to the invention cover the pressure and conversion ranges ranging from mild hydrocracking to high pressure hydrocracking. By mild hydrocracking is meant hydrocracking leading to moderate conversions, generally less than 40%, and operating at low pressure, generally between 2 MPa and 6 MPa.

The catalyst according to the invention can be used alone, in a single or several fixed-bed catalytic beds, in one or several reactors, in a so-called one-step hydrocracking scheme, with or without liquid recycling of the unconverted fraction, or alternatively in a so-called two-stage hydrocracking scheme, optionally in combination with a hydrorefining catalyst located upstream of the catalyst of the present invention.

According to a third mode of use, said hydrotreating and/or hydrocracking process according to the invention is advantageously implemented as pretreatment in a fluidized bed catalytic cracking process (or FCC process for Fluid Catalytic Cracking according to the terminology Anglo-Saxon). The pretreatment operating conditions in terms of temperature range, pressure, hydrogen recycling rate, hourly volume rate are generally identical to those described above for the hydrotreatment and/or hydrocracking processes of vacuum distillates. The FCC process can be carried out in a conventional manner known to those skilled in the art under the appropriate cracking conditions in order to produce lower molecular weight hydrocarbon products. For example, a summary description of catalytic cracking can be found in ULLMANS ENCYCLOPEDIA OF INDUSTRIAL CHEMISTRY VOLUME A 18, 1991, pages 61 to 64.

According to a fourth mode of use, said hydrotreating and/or hydrocracking process according to the invention is a process for hydrotreating (in particular hydrodesulfurization) a gasoline cut in the presence of at least one catalyst according to 'invention.

Unlike other hydrotreating processes, the hydrotreating (in particular hydrodesulfurization) of gasolines must make it possible to respond to a double antagonistic constraint: ensuring deep hydrodesulfurization of gasolines and limiting the hydrogenation of the unsaturated compounds present in order to limit the loss of octane number.

The feed is generally a hydrocarbon cut having a distillation range of between 30 and 260°C. Preferably, this hydrocarbon cut is a cut of the gasoline type. Very preferably, the gasoline cut is an olefinic gasoline cut resulting for example from a catalytic cracking unit (Fluid Catalytic Cracking according to the Anglo-Saxon terminology).

The hydrotreating process consists in bringing the hydrocarbon cut into contact with the catalyst according to the invention and hydrogen under the following conditions: at a temperature between 200 and 400° C., preferably between 230 and 330° C, at a total pressure of between 1 and 3 MPa, preferably between 1.5 and 2.5 MPa, at an Hourly Volume Velocity (VVH), defined as being the volume flow rate of charge relative to the volume of catalyst, comprised between 1 a.m. and 10 a.m.^-1, preferably between 2 and 6 hours^-1and at a hydrogen/petrol feedstock ratio of between 100 and 600 Nl/l, preferably between 200 and 400 Nl/l.

The process for the hydrotreatment of gasolines can be carried out in one or more reactors in series of the fixed bed type or of the bubbling bed type. If the method is implemented by means of at least two reactors in series, it is possible to provide a device for removing H ₂ S from the effluent from the first hydrodesulphurization reactor before treating said effluent in the second hydrodesulfurization reactor.

The following examples demonstrate the significant gain in activity on the catalysts prepared according to the process according to the invention compared to the catalysts of the prior art and specify the invention without however limiting its scope.

EXAMPLES

Example 1: Preparation of catalysts CoMoP on alumina without organic compound C1 and C2 (not in accordance with the invention).

On an alumina support having a BET surface of 230 m ² /g, a pore volume measured by mercury porosimetry of 0.78 ml/g and an average pore diameter of 11.5 nm defined as the median volume diameter by mercury porosimetry and which comes in the "extruded" form, cobalt, molybdenum and phosphorus are added. The impregnation solution is prepared by dissolving at 90°C molybdenum oxide (21.1 g) and cobalt hydroxide (5.04 g) in 11.8 g of an aqueous solution of phosphoric acid at 85% weight. After dry impregnation, the extrudates are left to mature in an atmosphere saturated with water for 24 hours at ambient temperature, then they are dried at 90° C. for 16 hours. The dried catalyst precursor thus obtained is denoted C1. Calcination of catalyst precursor C1 at 450° C. for 2 hours leads to calcined catalyst C2. The final metal composition of the precursor of catalyst C1 and of catalyst C2 expressed in the form of oxides and related to the weight of the dry catalyst is then as follows: MoO ₃ = 19.5 ± 0.2% by weight, CoO = 3.8 ±0.1% by weight and P ₂ O ₅ =6.7 ±0.1% by weight.

Example 2: Preparation of catalysts CoMoP on C3 alumina (not in accordance with the invention) and C4 and C5 (in accordance with the invention) by co -impregnation.

Cobalt, molybdenum and phosphorus are added to the alumina support described previously in example 1 and which is in the “extruded” form. The impregnation solution is prepared by dissolving at 90° C. molybdenum oxide (28.28 g) and cobalt hydroxide (6.57 g) in 15.85 g of an aqueous solution of acid 85% phosphoric and water. After homogenization of the preceding mixture, 38 g of citric acid were added before adjusting the volume of solution to the porous volume of the support by adding water. The molar ratio (citric acid)/Mo is equal to 1 mol/mol and that (citric acid)/Co is equal to 2.7 mol/mol. After dry impregnation, the extrudates are left to mature in an atmosphere saturated with water for 24 hours at ambient temperature, then they are dried at 120° C. for 16 hours. The catalyst dried and added with citric acid thus obtained is denoted C3. The final composition of catalyst C3, expressed in the form of oxides and relative to the weight of the dry catalyst, is then as follows: MoO ₃ = 19.7 ± 0.2% by weight, CoO = 3.8 ± 0.1% by weight and P ₂ O ₅ =6.8±0.1% by weight.

Catalyst C4 is prepared analogously to catalyst C3, but after homogenization of the metal solution containing cobalt, molybdenum and phosphorus, diethyl tartrate is added, in a proportion of 0.9 mole per mole of molybdenum or 2 .5 moles per mole of cobalt. Catalyst C4 was left to mature in an atmosphere saturated with water for 12 hours at ambient temperature, then dried at 120° C. for 16 hours. The final composition of catalyst C4, expressed in the form of oxides and related to the mass of dry catalyst is then as follows: MoO ₃ = 19.5 ± 0.2% by weight, CoO = 3.5 ± 0.1% by weight and P ₂ O ₅ = 6.6 ± 0.1% by weight.

Catalyst C5 is prepared analogously to catalyst C3, but after homogenization of the metal solution containing cobalt, molybdenum and phosphorus, diethyl malate is added, in a proportion of 0.9 mole per mole of molybdenum or 2 .5 moles per mole of cobalt. Catalyst C5 was left to mature in an atmosphere saturated with water for 12 hours at ambient temperature, then dried at 120° C. for 16 hours. The final composition of catalyst C5, expressed in the form of oxides and related to the mass of dry catalyst is then as follows: MoO ₃ = 19.6 ± 0.2% by weight, CoO = 3.8 ±0.1% by weight and P ₂ O ₅ = 6.7 ± 0.1% by weight.

Example 3: Preparation of the catalyst CoMoP on C6 alumina (in accordance with the invention) by post-additivation.

18 g of catalyst precursor C1 described above in Example 1 and which is in the "extruded" form are impregnated with an aqueous solution containing 4.1 g of diethyl tartrate and whose volume is equal to the pore volume of the precursor. catalyst C1. The amounts involved are such that the amount of diethyl tartrate is 0.8 mole per mole of molybdenum (corresponding to 2.2 moles per mole of cobalt). The extrudates are left to mature in an atmosphere saturated with water for 16 hours at room temperature. The precursor of catalyst C6 is then dried at 120° C. for 2 hours to give catalyst C6. The final metal composition of the C6 catalyst relative to the weight of the dry catalyst is: MoO ₃ = 19.5 ± 0.2% by weight, CoO = 3.7 ± 0.1% by weight and P ₂ O ₅ =6.8 ± 0.1% by weight.

Example 4: Preparation of the catalyst CoMoP on C7 alumina (in accordance with the invention) by post-additivation.

18 g of catalyst precursor C1 described above in Example 1 and which is in the "extruded" form are impregnated with an aqueous solution containing 3.8 g of diethyl malate and whose volume is equal to the pore volume of the precursor. catalyst C1. The amounts involved are such that the amount of diethyl malate is 0.8 mole per mole of molybdenum (corresponding to 2.2 moles per mole of cobalt). The extrudates are left to mature in an atmosphere saturated with water for 16 hours at room temperature. The precursor of catalyst C7 is then dried at 120° C. for 2 hours to give catalyst C7. The final metal composition of the C7 catalyst relative to the weight of the dry catalyst is: MoO ₃ = 19.7 ± 0.2% by weight, CoO = 3.9 ± 0.1% by weight and P ₂ O ₅ =6.7 ± 0.1% by weight.

Example 5: Evaluation in hydrodesulphurization (HDS) of diesel fuel of catalysts C1, C2 and C3 (not in accordance with the invention) and C4, C5, C6 and C7 (in accordance with the invention).

Catalysts C1, C2 and C3 (not in accordance with the invention) and C4, C5, C6 and C7 (in accordance with the invention) were tested in diesel HDS.

The characteristics of the diesel feedstock used are as follows: density at 15° C.=0.8522 g/cm ³ , sulfur content=1.44% by weight.

∙ Simulated Distillation (ASTM2887):

- IP: 155°C

- 10%: 247°C

- 50%: 315°C

- 90%: 392°C

- MP: 444°C

The test is carried out in an isothermal pilot reactor with a traversed fixed bed, the fluids circulating from bottom to top.

The catalyst precursors are sulphided beforehand in situ at 350° C. in the pressurized reactor by means of the gas oil of the test to which 2% by weight of dimethyl disulphide is added.

The hydrodesulphurization tests were carried out under the following operating conditions: a total pressure of 7 MPa, a catalyst volume of 30 cm ³ , a temperature of 330 to 360° C., with a hydrogen flow rate of 24 l/h and with a charge rate of 60 cm ³ /h.

The catalytic performances of the catalysts tested are given in Table 1. They are expressed in degrees Celsius with respect to catalyst C2 (comparative) chosen as reference: they correspond to the temperature difference to be applied to reach 50 ppm of sulfur in the effluent. A negative value means that the sulfur content target is reached for a lower temperature and that there is therefore a gain in activity. A positive value means that the sulfur content target is reached for a higher temperature and that there is therefore a loss of activity.

Table 1 clearly shows the gain in the catalytic effect provided by the organic compounds according to the invention. In fact, the catalysts C4, C5, C6 and C7 (according to the invention) exhibit a higher activity than those obtained for all the other catalysts evaluated.

The advantage of the catalysts according to the invention is therefore significant whatever their method of introduction, whereas they have a lower proportion of organic compound than catalyst C3, thus with an intrinsic efficiency greater than that of the other compounds of the existing prior art for which it is necessary to introduce a greater proportion of compound to observe a significant catalytic effect.

Catalyst
(comparative or
according to the invention) Compound
organic used and
molar ratio
compound / MB Fashion
introductory
of the compound
organic SDH activity C1 (comp) nil Not applicable Basis + 1.0°C C2 (comp) nil Not applicable Base C3 (comp) Citric acid -
1.0 mol/mol MB Co-impregnation Basis – 2.9°C C4 ( inv ) tartrate diethyl
0.9 mol/mol Mo Co-impregnation Basis -6.7°C C5 ( inv ) malate of diethyl
0.9 mol/mol Mo Co-impregnation Basis -6.1°C C6 ( inv ) tartrate diethyl
0.8 mol/mol Mo Post-additive Basis -5.9°C C7 ( inv ) malate of diethyl
0.8 mol/mol Mo Post-additive Basis -5.4°C

Table 1: Activities relating to iso-volume in diesel hydrodesulfurization of catalysts C1 and C3 (not in accordance with the invention) and C4, C5, C6 and C7 (in accordance with the invention) compared to catalyst C2 (not in accordance with the invention) ).

Claims (12)

Catalyst comprising a support based on alumina or silica or silica-alumina, at least one element from group VIII, at least one element from group VIB, and at least one compound of formula (I)
[Chem 3]

in which:
- R1 is a hydrocarbon radical comprising from 1 to 12 carbon atoms, saturated or not, linear, branched or cyclic,
- X is chosen from a hydrocarbon radical comprising from 1 to 12 carbon atoms, saturated or not, linear, branched or cyclic, a hydrogen atom and an alcohol function. Catalyst according to Claim 1, in which the compound of formula (I) is chosen from dimethyl tartrate, diethyl tartrate, diisopropyl tartrate, di-tert-butyl tartrate, dimethyl malate, diethyl, diisopropyl malate and dibutyl malate. Catalyst according to one of Claims 1 to 2, in which the content of group VIB element is between 5 and 40% by weight, expressed as group VIB metal oxide relative to the total weight of the catalyst and the content of group VIB element VIII is between 1 and 10% by weight expressed as group VIII metal oxide relative to the total weight of the catalyst. Catalyst according to one of Claims 1 to 3, in which the molar ratio of group VIII element to group VIB element in the catalyst is between 0.1 and 0.8. Catalyst according to one of Claims 1 to 4, which additionally contains phosphorus, the phosphorus content being between 0.1 and 20% by weight, expressed as P ₂ O ₅ relative to the total weight of the catalyst and the phosphorus molar ratio on the Group VIB element in the catalyst is greater than or equal to 0.05. Catalyst according to one of Claims 1 to 5, in which the content of compound of formula (I) is between 1 and 45% by weight relative to the total weight of the catalyst. Catalyst according to one of Claims 1 to 6, which additionally contains an organic compound other than the compound of formula (I) containing oxygen and/or nitrogen and/or sulphur. Catalyst according to Claim 7, in which the organic compound is chosen from a compound comprising one or more chemical functions chosen from a carboxylic, alcohol, thiol, thioether, sulphone, sulphoxide, ether, aldehyde, ketone, ester, carbonate, amine, nitrile, imide, oxime, urea, amide or compounds including a furan cycle or sugars. Catalyst according to Claim 8, in which the organic compound other than the compound of formula (I) is chosen from γ-valerolactone, 2-acetylbutyrolactone, triethyleneglycol, diethyleneglycol, ethyleneglycol, ethylenediaminetetra-acetic acid, maleic acid, malonic acid, citric acid, gluconic acid, glucose, fructose, sucrose, sorbitol, xylitol, γ-ketovaleric acid, dimethylformamide, 1-methyl- 2-pyrrolidinone, propylene carbonate, 2-methoxyethyl 3-oxobutanoate, bicine, tricine, 2-furaldehyde, 5-hydroxymethylfurfural, 2-acetylfuran,
5-methyl-2-furaldehyde, ascorbic acid, butyl lactate, ethyl lactate, butyl butyryllactate, ethyl 3-hydroxybutanoate, ethyl 3-ethoxypropanoate, acetate 2-ethoxyethyl, 2-butoxyethyl acetate, 2-hydroxyethyl acrylate, 1-vinyl-2-pyrrolidinone, 1,3-dimethyl-2-imidazolidinone, 1,5-pentanediol, 1- (2-hydroxyethyl)-2-pyrrolidinone, 1-(2-hydroxyethyl)-2,5-pyrrolidinedione, 5-methyl-2(3H)-furanone, 1-methyl-2-piperidinone, acid 4 -aminobutanoic acid, butyl glycolate, ethyl 2-mercaptopropanoate, ethyl 4-oxopentanoate, diethyl maleate, dimethyl maleate, dimethyl fumarate, diethyl fumarate, dimethyl adipate and dimethyl 3-oxoglutarate. Catalyst according to one of Claims 1 to 9, being at least partially sulfurized. Process for the preparation of a catalyst according to one of Claims 1 to 10, comprising the following stages:
a) at least one compound comprising an element from group VIB, at least one compound comprising an element from group VIII, at least one compound of formula (I) and optionally phosphorus is brought into contact with an alumina-based support or silica or silica-alumina, or a regenerated catalyst containing a support based on alumina or silica or silica-alumina, at least one element from group VIB, at least one element from group VIII and optionally phosphorus, with at least one compound of formula (I), so as to obtain a catalyst precursor,
b) said catalyst precursor resulting from step a) is dried at a temperature below 200° C., without subsequently calcining it. Use of the catalyst according to one of Claims 1 to 10 in a process for the hydrotreating and/or hydrocracking of hydrocarbon cuts.