关键词: 甲基氯硅烷, 直接合成法, 铜基催化剂, 反应速率, 选择性

Abstract: The copper-based catalyst promoted by a small quantity of zinc, tin and phosphorus was applied in the reaction between silicon powder and methyl chloride to synthesize methylchlorosilanes in a stirred bed. The effects of temperature, pressure and content of catalyst on the reaction rate and product selectivity were investigated. Under the conditions of 320℃ and 0.1 MPa, the reaction rate of 210 g/(kg×h) and the selectivity of 87.7% for dimethyldichlorosilane could be achieved in the steady period. Raising the temperature increased the reaction rate remarkably, while the selectivity began to decline above 330℃. The reaction rate obeyed first-order kinetic model to methyl chloride and the selectivity was hardly affected by the pressure below 0.3 MPa. Increasing the content of catalyst benefitted the reaction rate within limits, yet the steady period was shortened and the utilization efficiency of silicon reduced.

Key words: methylchlorosilane, direct synthesis process, copper-based catalyst, reaction rate, selectivity