Abstract: The present invention pertains to the technical field of energy resource chemical industry, and in particular relates to a continuous reaction device and process for synthesizing polyoxymethylene dimethyl ethers by using paraformaldehyde and methylal as feedstock or using trioxane and methylal as feedstock in the presence of an acidic catalyst. The continuous reaction device comprises multiple slurry bed stirred tank reactors connected in series or in combination of series connection and parallel connection, and also comprises an on-line solid-liquid separation device to perform separation of the reaction mixture from the catalyst. Each of the tank reactors is provided with an axial-flow stirring paddle having 2-6 blades per layer, to ensure sufficient mixing of the reactants with the catalyst.

Abstract: The present invention pertains to the technical field of energy resource chemical industry, and in particular relates to a process for producing polyoxymethylene dimethyl ethers by directly using concentrated formaldehyde aqueous solution as feedstock to catalytically react with methanol and/or methylal in a fixed bed reactor. The method of the present invention uses concentrated formaldehyde aqueous solution with a concentration of over 80% by weight to react with methanol and/or methylal, in the presence of an acidic catalyst, to produce the required polyoxymethylene dimethyl ethers.