Patent ID: 7999140

Claim:
A process for preparing a polyoxymethylene dialkyl ether of the following formula: H 2m+1 C m O(CH 2 O) n C m H 2m+1 wherein n is an integer of from 2 to 10, and each m is independently 1 or 2, and wherein said process comprises: reacting a reaction mixture comprising: a dialkyl ether selected from the group consisting of dimethyl ether, methyl ethyl ether and diethyl ether; trioxane; and an acidic catalyst, wherein said reaction mixture comprises less than 1 wt. % of water, based on a total weight of said reaction mixture, and wherein said reaction mixture does not contain methanol; obtaining by distillation from said reaction mixture a fraction comprising polyoxymethylene dialkyl ether where n='and 4; and recycling dialkyl ether, trioxane and polyoxymethylene dialkyl ether where n<3 and optionally n>4 into the reaction mixture.