Preparation method of chloromethyl ether for absorbent resin

The invention discloses a preparation method of chloromethyl ether for absorbent resin and solves the problems that hydrogen chloride gas is needed and waste acid is produced in the prior art. According to the preparation method, an organic hydrogen chloride source is added after methylal and paraformaldehyde are totally dissolved, water is dropwise added to initiate the reaction, and the method belongs to a chloromethylation method; a reaction solution obtained after the reaction is subjected to two stages of distillation, a finished chloromethyl ether product is recovered in the first stageof distillation, residual distillate is distillated in the second stage of distillation, and produced gas is recovered and can be used as a raw material for re-reaction; therefore, recycling of substances is improved, waste of useful substances is avoided, yield of chloromethyl ether is increased to a certain degree, residues obtained after the second stage of distillation are neutralized until pHis 7, and the waste acid