Hydrotreating and/or hydrocracking catalyst of hydrocarbons and preparation thereof

1. A hydrocarbon hydroconversion catalyst, comprising a medium with a base of at least one refractory oxide selected from the group consisting of alumina, silica and silica-alumina, wherein the at least one refractory oxide contains 0.1 to 10% by weight of at least one metal of group VIII, and 1 to 20% by weight of at least one metal of group VIB by weight on the Period Table of the Elements; and at least one organic compound with at least two oxime groups of the formula:

>C═NOR 1   (I)

where R 1 is chosen from among a hydrogen atom, alkyl, allyl, aryl, alkenyl or cycloaliphatic groups, and combinations thereof, and one or more of said groups can be substituted by at least one electron donor group.

2. The catalyst described in claim 1 , wherein the organic compound is the result of the reaction of an amine of formula (II) below

in which R 1 is chosen from among a hydrogen atom, alkyl, allyl, aryl, alkenyl or cycloaliphatic groups, and combinations thereof, and one or more of said groups can be substituted by an electron donor group, with a carbonyl compound of formula (III) below

where R 3 and R 4 , which are either identical to or different from one another, are chosen from among hydrogen, for only one of them, linear, ramified or cyclic alkyl, aryl, allyl or alkenyl groups, and combinations thereof, which themselves can be substituted by electron donor groups.

3. The catalyst described in claim 2 , wherein the amine of formula (II) is hydroxylamine.

4. The catalyst described in claim 2 , wherein the carbonyl compound of formula (III) is chosen from among carbonyl compounds that are naturally present in a hydrocarbon charge that is the result of the distillation of crude oil, or ketones and aldehydes.

5. The catalyst described in claim 1 , wherein said organic compound has a principal carbonaceous chain of 1 to 40 carbon atoms that is linear, ramified or partially or completely cyclic, that can be interrupted by heteroatoms chosen from among sulfur, nitrogen or oxygen, and the carbon atoms can be substituted by a hydrogen atom, alkyl or aryl groups, at least one oxime group, at least one hydroxyl, sulfide or polysulfide group, a thiol, thioacid, thioether or thioester group, sulfone or sulfoxide groups, amine, amide or imine groups, carboxyl, ether or ester groups, ketone or aldehyde groups, nitrate groups, phosphines or any other group with a free electron pair.

6. The catalyst described in claim 1 , wherein said organic compound is chosen from among dioximes and polyoximes comprising one or more alkyl, aryl, alkylaryl and arylalkyl groups.

7. The catalyst described in claim 6 , wherein said organic compound is chosen from among glyoxime, monoalkylglyoximes, dialkyloximes and polyoximes with carbonaceous chains including 1 to 10 carbon atoms that tolerate hydrogen and alkyl, aryl, alkylaryl and arylalkyl groups.

8. The catalyst described in claim 7 , wherein said compound is dimethylglyoxime.

9. The catalyst described in claim 1 , comprising at least 0.001 mole of said organic compound per mole of metal from groups VIB and VIII.

10. The catalyst described in claim 9 , comprising from 0.001 to 10 moles of said organic compound.

11. A process for preparing the catalyst described in claim 1 , comprising contacting a catalyst in a medium of a base of at least one refractory oxide, at least one metal of group VIII and at least one metal of group VIB with the organic compound of claim 1 , as a gas, diluted in a solvent, and/or in a hydrocarbon charge, to form the catalyst of claim 1 .

12. The process described in claim 11 , wherein said organic compound is a synthesized compound, obtained by reacting a carbonyl compound of formula (III), which may or may not be contained in the hydrocarbon charge being processed, with an amine of formula (II), by maintaining the mixture at a temperature between room temperature and 100° C., under pressure that is at least equal to atmospheric pressure.

13. The process described in claim 11 , wherein said organic compound is prepared in situ in a hydroconversion reactor, in the hydrocarbon charge being processed.

14. The process described in claim 11 , wherein the organic compound is prepared ex situ, and then deposited or impregnated on the catalyst.

15. A hydrocarbon hydrotreatment and/or hydrocracking process, after in situ or ex situ sulfidation of a catalyst of claim 1 without said organic compound, using at least one sulfide compound chosen from among hydrogen sulfide, sulfur, CS 2 , mercaptans, sulfides and/or polysulfides or hydrocarbon fractions with a boiling point of less than 400° C. containing sulfur compounds, or other compounds with a sulfidizing effect, comprising

contacting said catalyst with the organic compound of claim 1 in the form of a gas or in diluted form in a solvent, and

passing a hydrocarbon charge to be hydrotreated and/or hydrocracked over said catalyst,

wherein the organic compound can be provided as an additive of the hydrocarbon charge being converted, in addition to or in lieu of contacting the catalyst with compound in the form of a gas or in diluted form in a solvent.