Catalytic chlorofluorination process for producing CHClFCF.sub.3 and CHF.sub.2 CF.sub.3

A process for producing a halohydrocarbon compound of the formula CHF.sub.2 CF.sub.3 characterized by:

• (a) feeding a combination of components comprising (i) at least one halohydrocarbon starting compound selected from CHCl.dbd.CCl.sub.2, (ii) Cl.sub.2, (iii) HF and optionally, (iv) at least one halohydrocarbon recycle compound of the formula CHYClCF.sub.3 where Y is selected from the group consisting of H and Cl to the reaction zone, wherein the molar ratio of Cl.sub.2 to the total moles of CHCl.dbd.CCl.sub.2, CH.sub.2 ClCF.sub.3 and recycled CHCl.sub.2 CF.sub.3 is within the range of from 0.5:1 to 50:1;
• (b) contacting said combination of compounds in said reaction zone with a catalyst comprising chromium oxide at an elevated temperature to produce reaction zone products containing halohydrocarbon reaction products including CHF.sub.2 CF.sub.3 together with halohydrocarbons of the formula CHYClCF.sub.3 ;
• (c) recovering at least a portion of the reaction products from the reaction zone including CHF.sub.2 CF.sub.3 ;
• (d) optionally recycling a portion of the reaction zone products to said reaction zone;
• and
• (e) providing a catalyst contact time and temperature in said reaction zone and an amount of recycle of halohydrocarbons of the formula CHYClCF.sub.3 to said reaction zone sufficient to produce CHF.sub.2 CF.sub.3 in said recovered reaction products as the major component of the halogen-substituted hydrocarbon reaction products in said recovered reaction products.

A process for producing a halohydrocarbon compound of the formula CHF.sub.2 CF.sub.3, characterized by:

• (a) feeding a combination of components comprising (i) at least one halohydrocarbon starting compound selected from CHCl.dbd.CCl.sub.2 and CH.sub.2 ClCF.sub.3, (ii) Cl.sub.2, (iii) HF and (iv) at least one halohydrocarbon recycle compound of the formula CHYClCF.sub.3 where Y is selected from the group consisting of H and Cl to a reaction zone, wherein the molar ratio of Cl.sub.2 to the total moles of CHCl.dbd.CCl.sub.2, CH.sub.2 ClCF.sub.3 and recycled CHCl.sub.2 CF.sub.3 is within the range of 0.5:1 to 50:1;
• (b) contacting said combination of compounds in said reaction zone with a catalyst composition comprising a catalytically effective amount of chromium oxide or HF-activated chromium oxide at a temperature of at least about 200.degree. C. to produce reaction zone products containing halohydrocarbon reaction products including CHF.sub.2 CF.sub.3 together with halohydrocarbons of the formula CHYClCF.sub.3 ;
• (c) recovering at least a portion of the reaction products from the reaction zone including CHF.sub.2 CF.sub.3 ;
• (d) recycling a portion of the reaction zone products including at least one compound of the formula CHYClCF.sub.3 to said reaction zone;
• and
• (e) providing a catalyst contact time and temperature in said reaction zone and an amount of recycle of halohydrocarbons of the formula CHYClCF.sub.3 to said reaction zone sufficient to produce CHF.sub.2 CF.sub.3 in said recovered reaction products as the major component of the halogen-substituted hydrocarbon reaction products in said recovered reaction products.