Selective hydrogenation catalyst obtained from molten salts and an organic additive

Patent metadata

Field	Value
Publication number	US-2023047217-A1
Application number	US-202017784205-A
Country	US
Kind code	A1
Filing date	Dec 4, 2020
Priority date	Dec 17, 2019
Publication date	Feb 16, 2023
Grant date	—

Abstract

A selective hydrogenation catalyst that can be obtained by the process comprising at least the following steps:
a) the alumina support is brought into contact with at least one organic additive; b) the alumina support is brought into contact with at least one nickel metal salt, the melting point of said metal salt of which is between 20° C. and 150° C.; c) the solid mixture obtained on conclusion of steps a) and b) is heated with stirring; d) the catalyst precursor on conclusion of step c) is dried; e) a step of heat treatment of the dried catalyst precursor obtained on conclusion of step d) is carried out.

First claim

1 . A selective hydrogenation catalyst comprising a nickel-based active phase and an alumina support, said active phase not comprising a metal from Group VIB, said catalyst comprising a content of elemental nickel of greater than or equal to 1% by weight and less than 20% by weight relative to the total weight of the catalyst, the size of the nickel particles in the catalyst, measured in oxide form, is less than 18 nm, said catalyst being capable of being obtained by the process comprising at least the following steps:
a) the alumina support is brought into contact with at least one organic additive comprising oxygen and/or nitrogen, the molar ratio of the organic additive to the nickel being greater than 0.05 mol/mol; b) the alumina support is brought into contact with at least one nickel metal salt, at a temperature of less than the melting point of said nickel metal salt, in order to form a solid mixture, the ratio by weight of said metal salt to the alumina support being between 0.1 and 2.3,
steps a) and b) being carried out either successively in this order, or simultaneously;
c) the solid mixture obtained on conclusion of steps a) and b) is heated with stirring to a temperature between the melting point of said metal salt and 200° C., in order to obtain a catalyst precursor; d) the catalyst precursor on conclusion of step c) is dried at a temperature of less than 250° C. in order to obtain a dried catalyst precursor; e) a step of heat treatment of the dried catalyst precursor obtained on conclusion of step d) is carried out at a temperature of between 250 and 1000° C.

2 . The catalyst as claimed in claim 1 , characterized in that the size of the nickel particles 2 PET-3558 in the catalyst, measured in oxide form, is between 0.5 and 12 nm.

3 . The catalyst as claimed in claim 1 , characterized in that the size of the nickel particles in the catalyst, measured in oxide form, is between 1 and 5 nm.

4 . A process for preparing a selective hydrogenation catalyst comprising a nickel-based active phase and an alumina support, said active phase not comprising a metal from Group VIB, said catalyst comprising a content of elemental nickel of greater than or equal to 1% by weight and less than 20% by weight relative to the total weight of the catalyst, the nickel particle size in the catalyst, measured in oxide form, is less than 18 nm, said process comprising the following steps:
a) the alumina support is brought into contact with at least one organic additive comprising oxygen and/or nitrogen, the molar ratio of the organic additive to the nickel being greater than 0.05 mol/mol; b) the alumina support is brought into contact with at least one nickel metal salt, at a temperature of less than the melting point of said nickel metal salt, in order to form a solid mixture, the ratio by weight of said metal salt and the alumina support being between 0.1 and 2.3, steps a) and b) being carried out successively in this order, or simultaneously; c) the solid mixture obtained on conclusion of stages a) and b) is heated with stirring to a temperature between the melting point of said metal salt and 200° C., in order to obtain a catalyst precursor; d) the catalyst precursor on conclusion of step c) is dried at a temperature of less than 250° C. in order to obtain a dried catalyst precursor; e) a step of heat treatment of the dried catalyst precursor obtained on conclusion of step d) is carried out at a temperature of between 250 and 1000° C.

5 . The process as claimed in claim 4 , wherein the melting point of said metal salt is between 20° C. and 150° C.

6 . The process as claimed in claim 4 , wherein the molar ratio of said organic additive introduced in step a) to the element nickel introduced in step b) is between 0.1 and 5.0 mol/mol.

7 . The process as claimed in claim 4 , wherein steps a) and b) are carried out simultaneously.

8 . The process as claimed in claim 4 , wherein the organic additive is chosen from aldehydes including from 1 to 14 carbon atoms per molecule, ketones or polyketones including from 3 to 18 carbon atoms per molecule, ethers and esters including from 2 to 14 carbon atoms per molecule, alcohols or polyalcohols including from 1 to 14 carbon atoms per molecule and carboxylic acids or polycarboxylic acids including from 1 to 14 carbon atoms per molecule, or a combination of the various functional groups above.

9 . The process as claimed in claim 4 , wherein said organic additive of step a) is chosen from formic acid, formaldehyde, acetic acid, citric acid, oxalic acid, glycolic acid, malonic acid, levulinic acid, ethanol, methanol, ethyl formate, methyl formate, paraldehyde, acetaldehyde, γ-valerolactone, glucose and sorbitol.

10 . The process as claimed in claim 9 , wherein the organic additive is chosen from citric acid, formic acid, glycolic acid, levulinic acid and oxalic acid.

11 . The process as claimed in claim 4 , wherein step c) is carried out by means of a pan operating at a speed of between 4 and 70 revolutions per minute.

12 . The process as claimed in claim 4 , wherein, in step b), the ratio by weight of said metal salt to the alumina support is between 0.2 and 2.

13 . A process for the selective hydrogenation of polyunsaturated compounds containing at least 2 carbon atoms per molecule, contained in a hydrocarbon feedstock having a final boiling point below or equal to 300° C., which process being carried out at a temperature of between 0° C. and 300° C., at a pressure of between 0.1 and 10 MPa, at a hydrogen/(polyunsaturated compounds to be hydrogenated) mole ratio of between 0.1 and 10 and at an hourly space velocity of between 0.1 and 200 h −1 when the process is carried out in the liquid phase, or at a hydrogen/(polyunsaturated compounds to be hydrogenated) mole ratio of between 0.5 and 1000 and at an hourly space velocity of between 100 and 40000 h −1 when the process is carried out in the gas phase, in the presence of a catalyst as claimed in claim 1 .

14 . A process for the selective hydrogenation of polyunsaturated compounds containing at least 2 carbon atoms per molecule, contained in a hydrocarbon feedstock having a final boiling point below or equal to 300° C., which process being carried out at a temperature of between 0° C. and 300° C., at a pressure of between 0.1 and 10 MPa, at a hydrogen/(polyunsaturated compounds to be hydrogenated) mole ratio of between 0.1 and 10 and at an hourly space velocity of between 0.1 and 200 h −1 when the process is carried out in the liquid phase, or at a hydrogen/(polyunsaturated compounds to be hydrogenated) mole ratio of between 0.5 and 1000 and at an hourly space velocity of between 100 and 40000 h −1 when the process is carried out in the gas phase, in the presence of a catalyst obtained by the process as claimed in claim 4 .

Assignees

• Ifp Energies Now

Inventors

• Boualleg Malika
• Jothie Laetitia

Classifications

• B01J2235/00

  Indexing scheme associated with group B01J35/00, related to the analysis techniques used to determine the catalysts form or properties · CPC title

• B01J2235/30

  Scanning electron microscopy; Transmission electron microscopy · CPC title

• B01J35/393

  Metal or metal oxide crystallite size · CPC title

• Y02E60/50

  Fuel cells · CPC title

• C07C2521/04

  Alumina · CPC title