Producing alkyl halide(s) from cellulose etherification by prods. - by reaction of alcohol and/or di:alkyl ether by products with hydrogen chloride gas, etc.

摘要

In prepn. of alkyl halides by reacting alcohols and/or dialkyl ethers with HCl gas in a ZnCl2 melt (a) the reaction temp. is 100-450 deg.C; (b) a complexing ligand for the ZnCl2 is present in the melt; (c) the max. amts. of HCl used are 1.2 mols per mol of alcohol and 0.5 mols per mol of dialkyl ether; and (d) a bubble column- or loop-reactor is used. USE/ADVANTAGE - Alcohol and/or dialkyl ether by-prods. from e.g. the etherification of cellulose by alkyl halides can be worked up to give recyclable alkyl halide etherification agents, avoiding the pollution problems associated with disposal of by-prods. The alkyl halide prodn. can be effected efficiently without the need for a molar excess of HCl and any by prods. can be removed in such a way that they do not de-activate the catalyst.