Chromia based fluorination catalyst

Patent metadata

Field	Value
Publication number	US-2018022671-A1
Application number	US-201715703217-A
Country	US
Kind code	A1
Filing date	Sep 13, 2017
Priority date	Apr 8, 2005
Publication date	Jan 25, 2018
Grant date	—

Abstract

A chromia-based fluorination catalyst comprising at least one additional metal selected from zinc, nickel, aluminium 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

1 . A chromia-based fluorination catalyst consisting of:
amorphous chromia; zinc oxide in a total amount of zinc of from 0.5 to 25% by weight of the catalyst; and crystalline chromium oxide in a total amount of from 0.1 to 2.5% by weight of the catalyst; which catalyst is supported or unsupported.

2 . A catalyst according to claim 1 having a surface area of at least 50 m2/g.

3 . A catalyst according to claim 2 having a surface area of from 70 to 250 m2/g.

4 . A catalyst according to claim 1 having a sulphate content of less than 10% w/w.

5 . 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 300 to 600° C. for a period of from 1 to 12 hours in an atmosphere of nitrogen or an atmosphere having an oxygen level of from 0.1 to 10% v/v in nitrogen.

6 . A method for prefluorinating a catalyst according to claim 1 , which method comprises heat treating the catalyst at a temperature of from 250 to 500° C. for a period of from 1 to 16 hours at atmospheric or superatmospheric pressure in the presence of hydrogen fluoride.

7 . 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 .

8 . A process for producing a fluorinated hydrocarbon, which process comprises reacting a halogenated hydrocarbon with hydrogen fluoride in the presence of a catalyst produced according to the method of claim 6 .

9 . A process according to claim 7 that is carried out at elevated temperature in the vapour phase.

10 . A process according to claim 7 for the production of 1,1,1,2-tetrafluoroethane or penta-fluoroethane.

Assignees

• Mexichem Amanco Holding Sa

Inventors

• Sharratt Andrew P
• Scott John D

Classifications

• C07C17/21

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

• C07C17/206 Primary

  the other compound being HX · CPC title

• B01J23/26 Primary

  Chromium · CPC title

• C07C19/08

  containing fluorine · CPC title

• B01J23/652

  Chromium, molybdenum or tungsten · CPC title