Vanadium-based catalyst and preparation method therefor

Patent metadata

Field	Value
Publication number	US-10940462-B2
Application number	US-201716622448-A
Country	US
Kind code	B2
Filing date	Jun 13, 2017
Priority date	Jun 13, 2017
Publication date	Mar 9, 2021
Grant date	Mar 9, 2021

Abstract

A vanadium-based catalyst comprises an active phase carried on a carrier. The active phase comprises vanadium oxide, potassium sulfate, sodium sulfate, and assistants. The carrier comprises ultra-large-pore silicon dioxide and diatomite, the average pore size of the ultra-large-pore silicon dioxide ranges from 100 nm to 500 nm, and the diatomite is a refined diatomite having a silicon dioxide content of higher than 85% after refinement. The preparation method for the vanadium-based catalyst comprises: 1) mixing potassium vanadium and potassium hydroxide, and allowing a prepared mixed solution and sulfuric acid to carry out a neutralization reaction; and 2) mixing a neutralization reaction product in step 1) with the carrier and sodium sulfate, and carrying out rolling, band extrusion, drying and roasting to prepare the vanadium-based catalyst, assistant compounds being added in step 1) and/or step 2).

First claim

The invention claimed is:

1. A vanadium-based catalyst, comprising: an active phase loaded on a carrier, wherein the active phase comprises vanadium oxide, potassium sulfate, sodium sulfate, and an auxiliary agent, and the carrier comprises an ultra-large-pore silica and a diatomite, wherein the ultra-large-pore silica has an average pore diameter ranging from 100 to 500 nm, and the diatomite is a purified diatomite having a silica content of more than 85%.

2. The vanadium-based catalyst according to claim 1 , wherein the ultra-large-pore silica has an average pore diameter ranging from 150 to 400 nm.

3. The vanadium-based catalyst according to claim 1 , wherein the active phase is present in an amount ranging from 30% to 40% by weight, and the carrier is present in an amount ranging from 60% to 70% by weight.

4. The vanadium-based catalyst according to claim 1 , wherein based on a total weight of the vanadium-based catalyst, vanadium oxide is present in an amount ranging from 6.5% to 8.5% by weight; a molar ratio of potassium element to vanadium element is (2.5-4.0):1; the auxiliary agent is present in an amount ranging from 0.5% to 2.0% by weight; and sodium sulfate is present in an amount ranging from 3.0% to 6.0% by weight.

5. The vanadium-based catalyst according to claim 1 , wherein based on a total weight of the vanadium-based catalyst, the ultra-large-pore silica is present in an amount ranging from 8.0% to 20.0% by weight.

6. A method for preparing a vanadium-based catalyst according to claim 1 , comprising steps of:
1) mixing potassium vanadate and potassium hydroxide to form a mixed solution, and subjecting the mixed solution and sulfuric acid to a neutralization reaction; and
2) mixing a product of the neutralization reaction in step 1) with a carrier and sodium sulfate to form a mixture, and subjecting the mixture to grinding, pressing, extruding, drying, and roasting to prepare a vanadium-based catalyst, the carrier comprising an ultra-large-pore silica and a diatomite,
wherein the ultra-large-pore silica has an average pore diameter ranging from 100 to 500 nm, and the diatomite is purified diatomite having a silica content of more than 85%; and
wherein an auxiliary compound is added in step 1) and/or step 2).

7. The method according to claim 6 , wherein in step 1), potassium sulfite is added in preparing the mixed solution.

8. The method according to claim 7 , wherein the molar ratio of potassium sulfite to potassium vanadate is in a range of 1:(0.9-1).

9. The method according to claim 6 , wherein in the carrier, the weight ratio of the ultra-large-pore silica to the diatomite is in a range of (6-20):(40-55).

10. The method according to claim 9 , wherein in the carrier, the weight ratio of the ultra-large-pore silica to the diatomite is in a range of (8-18):(40-52).

11. The method according to claim 6 , wherein preparation of the ultra-large-pore silica comprises a step of using colloidal microspheres of polystyrene having a particle diameter ranging from 120 to 550 nm in a silica sol.

12. The method according to any claim 6 , wherein the auxiliary compound is at least one selected from a group consisting of a phosphorus-containing compound and a cesium-containing compound.

13. The method according to claim 12 , wherein the auxiliary compound is at least one selected from a group consisting of phosphoric acid, cesium hydroxide, and cesium sulfate.

14. A method for preparing SO 3 by oxidizing SO 2 , comprising: contacting a gas stream containing SO 2 with a catalyst according to claim 1 , to obtain a gaseous product containing SO 3 .

15. A method for preparing SO 3 by oxidizing SO 2 , comprising: contacting a gas stream containing SO 2 with a catalyst prepared according to the method of claim 6 , to obtain a gaseous product containing SO 3 .

Assignees

• China Petroleum & Chem Corp
• Sinopec Nanjing Res Institute Of Chemical Industry Co Ltd

Inventors

• Tian Xianguo
• Wei Shixin
• Dong Tianlei
• Yin Huiqin
• Xie Tianming
• He Jian

Classifications

• B01J27/055

  with alkali metals, copper, gold or silver · CPC title

• B01J23/22 Primary

  Vanadium · CPC title

• B01J21/16

  Clays or other mineral silicates · CPC title

• B01J21/08

  Silica · CPC title

• B01J37/088

  Decomposition of a metal salt · CPC title