Effects of individual promoters on the Direct Synthesis of methylchlorosilanes
Effects of individual promoters on the Direct Synthesis of methylchlorosilanes
复制标题
DOI：
10.1016/j.jcat.2009.06.026
复制
发表时间：
2009-09
影响因子：
7.3
通讯作者：
Alexander D. Gordon;B. Hinch;D. Strongin
中科院分区：
文献类型：
--
作者：
Alexander D. Gordon;B. Hinch;D. Strongin
工业上相关的直接合成涉及甲基氯与硅在铜催化剂(用锌、锡和磷促进)的存在下反应，称为接触质量，生成甲基氯硅烷。采用原位衰减全反射傅里叶变换红外光谱(ATR-FTIR)与流动反应研究相结合的方法，研究了在300℃下反应(1bar CH3Cl)过程中工作催化剂表面组成与产物选择性之间的关系。与P促进和铜-硅(非促进)接触质量相比，锡和锌促进的铜-硅接触质量提高了二甲基二氯硅烷的反应选择性。结果表明，与锡促进的接触质量有关的硅转化率高于与锌和未促进的接触质量有关的硅转化率。ATR-FTIR结果表明，锡的促进导致了表面甲基物种的稳定和较高的浓度。与锡或锌的促进相反，磷的促进导致了接触体表面明显的甲基碎裂，这与其对二甲基二氯硅烷的选择性较低是一致的。
The industrially relevant Direct Synthesis involves the reaction of methyl chloride with silicon in the presence of a copper catalyst (promoted with Zn, Sn, and P), termed the contact mass, to form methylchlorosilanes. In situ attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) coupled with flow reactor studies was used to help understand the relationship between the composition of the working catalytic surface and product selectivity during reaction (1bar CH3Cl at 300°C). Promotion of copper–silicon contact masses with Sn and Zn increased the selectivity of the reaction for dimethyldichlorosilane compared to P-promoted and copper–silicon (unpromoted) contact masses. Results showed that the rate of Si conversion associated with the Sn-promoted contact mass was higher than the Si conversion rate associated with the Zn and unpromoted contact masses. ATR-FTIR results suggested that Sn promotion led to a stabilization and relatively high concentration of surface methyl species. In contrast to Sn or Zn promotion, P promotion led to significant methyl fragmentation on the contact mass surface, consistent with its relatively low selectivity toward dimethyldichlorosilane.