Process for reducing the fluorine content of halocarbons
AssigneeE. I. Du Pont de Nemours and Company
InventorsV. N. Mallikarjuna Rao, Steven H. Swearingen
Life of this patent
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Abstract
The fluorine content of an acyclic saturated compound of the formula C.sub.n F.sub.a X.sub.b having at least one carbon with at least two fluorine substituents (wherein each X is independently selected from Cl and Br, and wherein n is 1 to 4, a is 2 to 10, b is 0 to 8, and a+b equals 2n+2) is reduced by reacting the acyclic saturated compound with HCl in the vapor phase at an elevated temperature in the presence of a catalyst, the mole ratio of HCl to the acyclic saturated compound being at least about 2:1.
Claims20
A method for reducing the fluorine content of an acyclic saturated compound of the formula C.sub.n F.sub.a X.sub.b wherein each X is independently selected from the group consisting of chlorine and bromine, wherein n is 1 to 4, a is 2 to 10, b is 0 to 8, and a+b equals 2n+2, and wherein the acyclic saturated compound has at least one carbon with at least two fluorine substituents, comprising the step of:
- reacting said acyclic saturated compound with HCl in the vapor phase at a temperature in the range of from about 250.degree. C. to 550.degree. C. in the presence of a catalyst, the mole ratio of HCl to said acyclic saturated compound being at least about 2:1.
A process for reducing the fluorine content of a chlorofluoroethane consisting of carbon, chlorine and fluorine and having at least one carbon with at least two fluorine substituents, comprising the steps of:
- reacting said chlorofluoroethane with a fluorine-reducing reagent consisting essentially of HCl in the vapor phase at a temperature in the range of from about 300.degree. C. to 450.degree. C. in the presence of a catalyst comprising aluminum fluoride to produce Cl.sub.2 C.dbd.CCl.sub.2, the mole ratio of HCl to said chlorofluoroethane being at least about 5:1.
A process for reducing the fluorine content of an acyclic saturated compound of the formula C.sub.n F.sub.a wherein n is 1 to 4, and a equals 2n+2 comprising the step of:
- reacting said acyclic saturated compound with HCl in the vapor phase at a temperature in the range of from about 250.degree. to 550.degree. C. in the presence of a chromium oxide catalyst, the mole ratio of HCl to said acyclic saturated compound being at least about 5:1.
Dependencies are inferred from the claim text.