The invention provides a method for
continuous production of polyformaldehyde
dimethyl ether. The method is characterized by comprising the following steps: a) feeding
dimethoxymethane and hot-melted
paraformaldehyde into a
fixed bed reactor and adopting an acidic resin catalyst, so as to prepare polyformaldehyde
dimethyl ether (DMM3-8), wherein the
reaction temperature is 120-180 DEG C and the pressure is 0.1-10 MPa; b) cooling the
reaction product, and then performing adsorptive separation through a dehydrating
tower, so as to obtain polyformaldehyde
dimethyl ether of which most water,
cytidine glycol and
hemiacetal are desorbed; c) feeding the polyformaldehyde dimethyl
ether subjected to
desorption into a
distillation tower for separation, wherein most of a low-boiling component (
dimethoxymethane (DMM)), poly-di-
formaldehyde dimethyl
ether (DMM2), a by-product (
methanol) and triformol are extracted first, and then the materials in a
tower kettle are fed into a rectifying tower in the next step, so as to extract the rest of the DMM2 and the triformol; and d) returning the low-boiling component (
dimethoxymethane (DMM)), the
methanol, the DMM2 and the triformol, which are evaporated out by the
distillation tower and the rectifying tower in the last step, into the
fixed bed reactor to continue to react to prepare polyformaldehyde dimethyl
ether.