Synthesis of methyl methacrylate by vapor phase condensation of formaldehyde with propionate derivatives

摘要

The gas phase condensation of formaldehyde with propionic acid, propionic anhydride, and methyl propionate was studied over a series of V-Si-P catalysts of varying atomic ratios. Propionic anhydride gave the maximum yield of methacrylic acid (56/100, based on formaldehyde fed to the reactor) at 300 deg.C, 2 atm, 290 cc g~1 h~1 and a stoichiometric anhydride/ formaldehyde ration of 2:1. This yield was obtained for the optimum V-Si-P catalyst, which had an atomic ratio of 1:10:2.8. this is the highest yield reported to data for the heterogeneous catalytic condensation of propionic anhydride with formaldehyde.