| abstract |
Disclosed is a process for production of acrolein from glycerin, which shows a reduced over-time decrease in the acrolein yield. The process comprises dehydrating glycerin in the presence of a catalyst having a metal phosphate, wherein the process uses one or more metal phosphates selected from an aluminum salt, a zirconium salt, a manganese salt, an alkali metal salt [provided that the alkali metal is sodium, potassium or cesium and the ratio between the molar number (M) of the alkali metal and the molar number (P) of phosphoric acid (i.e., M/P ratio) in the metal phosphate is 2.0 or less], an alkali earth metal salt [provided that the ratio between the molar number (M) of the alkali earth metal and the molar number (P) of phosphoric acid (i.e., M/P ratio) in the metal phospahte is 1.0 or less], and the like. |