Catalyst and method for preparing light olefins by direct conversion of syngas

Patent metadata

Field	Value
Publication number	US-11084026-B2
Application number	US-201816618751-A
Country	US
Kind code	B2
Filing date	Aug 2, 2018
Priority date	Jun 2, 2017
Publication date	Aug 10, 2021
Grant date	Aug 10, 2021

Abstract

A process for direct synthesis of light olefins uses syngas as the feed raw material. This catalytic conversion process is conducted in a fixed bed or a moving bed using a composite catalyst containing components A and B (A+B). The active ingredient of catalyst A is metal oxide; and catalyst B is an oxide supported zeolite. A carrier is one or more of Al2O3, SiO2, TiO2, ZrO2, CeO2, MgO and Ga2O3 having hierarchical pores; the zeolite is one or more of CHA and AEI structures. The loading of the zeolite is 4%-45% wt. A weight ratio of the active ingredients in the catalyst A and the catalyst B is within a range of 0.1-20, and preferably 0.3-5. The total selectivity of the light olefins comprising ethylene, propylene and butylene can reach 50-90%, while the selectivity of a methane byproduct is less than 15%.

First claim

The invention claimed is:

1. A catalyst comprising catalyst component A and catalyst component B,
wherein the catalyst component A and the catalyst component B are mechanically mixed, wherein the catalyst component A comprises a metal oxide and the catalyst component B comprises a zeolite supported on a carrier,
wherein the carrier is selected from porous Al 2 O 3 , SiO 2 , TiO 2 , ZrO 2 , CeO 2 , MgO, Ga 2 O 3 , and mixtures thereof, the zeolite is selected from a CHA zeolite, an AEI zeolite, or mixtures thereof, wherein a loading of the zeolite is 4%-45% wt of the component B; and the metal oxide is selected from MnO, MnCr 2 O 4 , MnAl 2 O 4 , MnZrO 4 , ZnCr 2 O 4 , ZnAl 2 O 4 , CoAl 2 O 4 , FeAl 2 O 4 , and mixtures thereof.

2. The catalyst according to claim 1 , wherein the carrier has a specific surface area of 30-250 m 2 /g, a pore volume of 0.25-0.80 ml/g, a mesoporous specific surface area of 30-75% and a macroporous specific surface area of 25-70% of the specific surface area.

3. The catalyst according to claim 1 , wherein component A is selected from MnCr 2 O 4 , MnAl 2 O 4 , MnZrO 4 , ZnAl 2 O 4 , CoAl 2 O 4 , FeAl 2 O 4 , and mixtures thereof.

4. The catalyst according to claim 1 , wherein a weight ratio between the metal oxide in the catalyst component A and the catalyst component B is within a range of 0.1-20.

5. The catalyst according to claim 1 , wherein the metal oxide is in a form of crystals having a size of 5-30 nm, and oxygen vacancies residing within a depth of 0.3 nm from a surface of the crystal, wherein a weight of oxygen atoms in the metal oxide is less than 80% of a weight of a stoichiometric amount of oxygen atoms in the metal oxide.

6. The catalyst according to claim 1 , wherein the catalyst component A further comprises a dispersing agent selected from Al 2 O 3 , SiO 2 , Cr 2 O 3 , ZrO 2 , TiO 2 , and mixtures thereof, and a weight of the dispersing agent is 0.05-90 wt % of the weight of the catalyst component A.

7. A method for synthesis of light olefins directly from syngas, comprising contacting a syngas with the catalyst of claim 1 at a pressure of the syngas of 0.5-10 MPa, a reaction temperature of 300-600° C., a syngas space velocity of 300-10000 h −1 , and wherein a molar ratio of H 2 to CO in the syngas is 0.2-3.5.

8. The catalyst according to claim 4 , wherein the weight ratio is within the range of 0.3-5.

9. The catalyst according to claim 5 , wherein the weight of oxygen atoms in the metal oxide is 10%-80% of the weight of a stoichiometric amount of oxygen atoms in the metal oxide.

10. The catalyst according to claim 5 , wherein a oxygen vacancy is 20-90%, wherein the oxygen vacancy is a percentage of a weight of oxygen atoms in the metal oxide in a weight of the stoichiometric amount of oxygen atoms in the metal oxide.

11. The catalyst according to claim 10 , wherein the oxygen vacancy is 40-90%.

12. The catalyst according to claim 11 , wherein the surface oxygen vacancy is 50-90%.

13. The catalyst according to claim 1 , consisting of the catalyst component A and the catalyst component B.

14. The catalyst according to claim 1 , wherein the mechanical mixing is stirring, ball milling, shaking table mixing, or grinding.

Assignees

• Dalian Inst Chem & Physics Cas

Inventors

• Pan Xiulian
• Jiao Feng
• Bao Xinhe

Classifications

• B01J21/066

  Zirconium or hafnium; Oxides or hydroxides thereof · CPC title

• B01J29/7015

  CHA-type, e.g. Chabazite, LZ-218 · CPC title

• C07C2523/75

  Cobalt · CPC title

• B01J37/04

  Mixing {(B01J37/0009, B01J37/0018 take precedence)} · CPC title

• C07C1/0445

  Preparation; Activation · CPC title