| 摘要 |
PURPOSE:To produce the titled compound from an alkylbenzene, economically in high yield, by using two or more kinds of potassium-containing dehydrogenation catalyst having different potassium contents in an adiabatic fixed-bed reactor, and placing the catalysts from the feeding-side of the raw material gas downward in the order of catalyst having lower potassium content. CONSTITUTION:An alkenylbenzene such as ethylbenzene is produced in an adiabatic fixed-bed reactor at a high temperature in the presence of steam and a potassium-containing dehydrogenation catalyst composed mainly of K2O-Fe2O3. In the above reactor, two or more kinds of the above catalysts having different potassium content are arranged from the feeding-side of the raw material downward in the order of the catalyst having lower potassium content. When the amount of steam is decreased to reduce the production cost, the pulverization of the catalyst tends to occur by the dissipation of potassium. The present process is effective to suppress the pulverization of the catalyst to elongate the catalytic life, and to give the objective compound in high conversion, selectivity and yield. |
