Chromia based fluorination catalyst

Patent metadata

Field	Value
Publication number	US-9771309-B2
Application number	US-88797206-A
Country	US
Kind code	B2
Filing date	Apr 10, 2006
Priority date	Apr 8, 2005
Publication date	Sep 26, 2017
Grant date	Sep 26, 2017

Abstract

A chromia-based fluorination catalyst comprising at least one additional metal selected from zinc, nickel, aluminum and magnesium in which from 0.1 to 8.0% by weight of the catalyst is in the form of one or more crystalline compounds of chromium and/or one or more crystalline compounds of the at least one additional metal. The catalyst can be used in processes for producing a fluorinated hydrocarbon.

First claim

The invention claimed is:

1. A chromia-based fluorination catalyst comprising from 6% to 25% by weight of at least one additional metal selected Iron zinc, nickel, aluminium and magnesium in which from 0.5 to 2.5% by weight of the catalyst is in the form of one or more crystalline compounds of chromium.

2. A catalyst according to claim 1 , wherein the additional metal is zinc.

3. A catalyst according to claim 1 having a surface area of at least 50 m 2 /g.

4. A catalyst according to claim 3 having a surface area of from 70 to 250 m 2 /g.

5. A canal according to claim 1 having a sulphate content of less 10% w/w.

6. A method for producing a catalyst as defined claim 1 , which method comprises heat treating an amorphous catalyst precursor at a temperature of from about 300 to about 600° C. for a period of from about 1 to about 12 hours in an atmosphere of nitrogen or an atmosphere having an oxygen level of from about 0.1 to about 10% v/v in nitrogen.

7. A method for producing a catalyst as defined in claim 1 , which method comprises heat treating an amorphous catalyst precursor at a temperature of from about 250 to about 500° C. for a period of from about 1 to about 16 hours at atmospheric or superatmospheric pressure in the presence of hydrogen fluoride.

8. A process for producing a fluorinated hydrocarbon, which process comprises reacting a halogenated hydrocarbon with hydrogen fluoride in the presence of a catalyst as defined in claim 1 .

9. A process according to claim 8 that is carried out at elevated temperature in the vapour phase.

10. A process according to claim 9 for the production of 1,1,1,2-tetrafluoroethane or pentafluoroethane.

Assignees

• Sharratt Andrew P
• Scott John D
• Mexichem Amanco Holding Sa

Inventors

• Sharratt Andrew P
• Scott John D

Classifications

• C07C17/206 Primary

  the other compound being HX · CPC title

• B01J23/26 Primary

  Chromium · CPC title

• C07C17/21

  with simultaneous increase of the number of halogen atoms · CPC title

• C07C19/08

  containing fluorine · CPC title

• B01J23/652

  Chromium, molybdenum or tungsten · CPC title