Chromia based fluorination catalyst

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.