RECOVERY OF METHYL METHACRYLATE

摘要

PURPOSE:To efficiently recover the objective compound from the bottom residue mentioned below using simple operations by bringing the bottom residue obtained in purification process of an esterification product into contact with a zeolite catalyst in gas phase in production of the subject compound using acetone cyanhydrin method. CONSTITUTION:In production of methyl methacrylate by reacting acetone cyanhydrin with sulfuric acid and methanol, the bottom residue obtained in purification of crude methyl methacrylate produced in esterification process is brought into contact with a zeolite catalyst preferably having 2-20 SiO2/Al2O3 molar ratio and -5.6-+4.8 pKa acid strength in gas phase after distillation of the bottom residue or without distillation, thus efficiently recovering the objective compound from a high boiling composition mainly composed of methyl 2-hydroxyisobutyrate and methyl 3-methoxyisobutyrate in the above-mentioned bottom residue in a high yield in a short time and stably for long hours without requirement of a large quantity of catalyst or solvent.