Method of improving selective hydrogenation of unsaturated hydrocarbon in aromatic fraction through catalyst pretreatment

Patent metadata

Field	Value
Publication number	US-12011709-B2
Application number	US-202217973669-A
Country	US
Kind code	B2
Filing date	Oct 26, 2022
Priority date	Oct 27, 2021
Publication date	Jun 18, 2024
Grant date	Jun 18, 2024

Abstract

Disclosed is a method for providing improved hydrogenation activity by pretreating a catalyst in a three-step manner before selective hydrogenation of unsaturated hydrocarbons in an aromatic fraction in the presence of an oxide-type bimetallic (particularly nickel-molybdenum) supported catalyst.

First claim

The invention claimed is:

1. A method for preparing a selective hydrogenation catalyst for an unsaturated hydrocarbon in an aromatic fraction, which comprises the steps of:
step a) providing a calcined catalyst containing nickel and molybdenum;
step b) sulfiding the calcined catalyst containing nickel and molybdenum to give a sulfided catalyst containing nickel and molybdenum;
step c) carrying out an oxidation treatment of the sulfided catalyst containing nickel and molybdenum at a temperature exceeding 250° C. and below 700° C. to give an oxidized catalyst containing nickel and molybdenum; and
step d) carrying out a reduction treatment of the oxidized catalyst containing nickel and molybdenum to give a reduced catalyst containing nickel and molybdenum.

2. The method of claim 1 , wherein the calcined catalyst containing nickel and molybdenum is a catalyst in which nickel and molybdenum are loaded on an inorganic support, an amount of nickel being 1 to 30 wt % and an amount of molybdenum being 2 to 40 wt %.

3. The method of claim 2 , wherein an atomic ratio of nickel to molybdenum in the calcined catalyst containing nickel and molybdenum is 1:0.1 to 10.

4. The method of claim 2 , wherein the inorganic support is at least one selected from the group consisting of alumina, silica, silica-alumina, aluminum phosphate, zirconia, titania, bentonite, kaolin, clinoptilolite, and montmorillonite.

5. The method of claim 2 , wherein step a) comprises the steps of:
step a1) preparing a catalyst in which one of nickel and molybdenum as active metals is loaded on an inorganic support; and
step a2) preparing a catalyst containing nickel and molybdenum by additionally supporting a remaining one of nickel and molybdenum.

6. The method of claim 2 , wherein the inorganic support has an average pore diameter in a range of 3 to 1000 nm, and a specific surface area (BET) in a range of 10 to 1000 m 2 /g.

7. The method of claim 1 , wherein step c) is performed at a temperature of 300 to 650° C.

8. The method of claim 1 , wherein a weight ratio of metal (nickel and molybdenum)/sulfur in the oxidized catalyst containing nickel and molybdenum in step c) is greater than 1.7 and less than 60.

9. The method of claim 1 , wherein step b) is performed at a temperature ranging from room temperature to 500° C. for 0.2 to 200 hours using, as a sulfiding agent, at least one sulfur compound selected from the group consisting of hydrogen sulfide, hydrogen disulfide, carbon disulfide, and alkyl sulfide.

10. The method of claim 9 , wherein step b) is performed using a sulfidation treatment solution in which the at least one sulfur compound is added to a hydrocarbon-based solvent, a concentration of the at least one sulfur compound in the sulfidation treatment solution being 0.001 to 50 wt %.

11. The method of claim 1 , wherein step c) is performed for 0.2 to 300 hours in an atmosphere of oxygen alone or in an atmosphere of a mixed gas in which oxygen is diluted with an inert gas, a heating rate being adjusted within a range of 0.1 to 20° C./min.

12. The method of claim 1 , wherein step d) is performed at 25 to 650° C. for 0.2 to 200 hours in a reducing atmosphere using hydrogen alone or hydrogen diluted with an inert gas.

13. The method of claim 1 , wherein step a) comprises:
a1) depositing a nickel precursor and a molybdenum precursor on an inorganic support simultaneously or sequentially to give a nickel-molybdenum deposited support; and
a2) firing the nickel-molybdenum deposited support in an oxygen-containing atmosphere to give the calcined catalyst containing nickel and molybdenum.

14. The method of claim 13 , wherein step a1) is carried out by impregnation, ion-exchange, and/or co-precipitation.

15. The method of claim 13 , wherein the nickel precursor is selected from the group consisting of nickel nitrate, nickel sulfate, nickel phosphate, nickel halide, nickel carboxylate, nickel hydroxide, nickel carbonate, acetylacetonate nickel complex, nickel acetate, and hydrate thereof, and
the molybdenum precursor is selected from the group consisting of molybdenum (II) acetate, ammonium (VI) molybdate, diammonium (III) dimolybdate, ammonium (VI) heptamolybdate, ammonium (VI) phosphomolybdate and similar sodium and potassium salts, molybdenum (III) bromide, molybdenum (III)-(V) chloride, molybdenum (VI) fluoride, molybdenum (VI) oxychloride, molybdenum (IV)-(VI) sulfide, molybdic acid and ammonium, sodium, and potassium salts thereof, and molybdenum (II-VI) oxide.

16. The method of claim 1 , wherein the nickel in the sulfided catalyst is converted into NiS and/or Ni 3 S 2 , while the molybdenum in the sulfided catalyst is converted into MoS 3 .

17. The method of claim 16 , wherein the oxidized catalyst has a formula of NiS a O b MoS c O d (0<(a+b) or (c+d)<2).

18. The method of claim 17 , wherein the ratio (on an atomic basis) of the amount of the nickel and molybdenum to the amount of remaining sulfur in the oxidized catalyst is adjusted within a range of 1.7<(Ni+Mo)/S<60.

19. The method of claim 17 , wherein the nickel in the reduced catalyst is in a form of Ni 0 , while the molybdenum in the reduced catalyst is in a form of Mo 4+ .

Assignees

• Sk Innovation Co Ltd
• Sk Geo Centric Co Ltd

Inventors

• Lee Sang Il
• Lee Ji Hoon

Classifications

• B01J35/394

  Metal dispersion value, e.g. percentage or fraction · CPC title

• C07C2523/883

  and nickel · CPC title

• C07C2523/882

  and cobalt · CPC title

• C07C2523/755

  Nickel · CPC title

• C07C2521/04

  Alumina · CPC title