Halogenated hydrocarbons are removed from hydrocarbon solvents for reuse in a butyl rubber process by contacting the halide containing hydrocarbon solvent with alumina at a temperature of at least 20°C. In particular 2-methyl-3-chloro- propene-1, 2-methyl-1,2-dibromo-3-chloropropane and tribromo isobutane or mixtures thereof can be removed from a hydrocarbon solvent by the process of this invention. The halide removal is preferably carried out at a temperature of at least 40°C, e.g., 60°C to 100°C.