Korean Chemical Engineering Research

The Korean Institute of Chemical Engineers (한국화학공학회)
권호 표지
DOI QR코드

DOI QR Code

Reaction Scheme on the Direct Synthesis of Methylchlorosilanes

Methylchlorosilanes의 직접 생산 반응에서 반응기구

  • Received : 2017.11.01
  • Accepted : 2017.12.15
  • Published : 2018.04.01
Download PDF
⟨ Previous Next ⟩

Abstract

Direct synthesis of methylchlorosilanes was developed by Rochow with addition of copper on the silicon surface as a catalyst and many research were followed. Most of research were focused on the increase of reaction activity through addition of promoters and concentrated on the increase of selectivity of DMDC. However, there are very few studies about the reaction mechanism. Although formation of DMDC was explained in literature, formation of other silanes were not mentioned at all. This reseach focused on the explanation about formation of all silanes obtained during direct reaction and TPD. Reaction paths were proposed by means of dissociative adsorption of methyl chloride and spillover of surface Cl and H. Surface silicon sites were considered as $=SlCl_2$ and $=Sl(CH_3)Cl$. The synthesis of all methylchlorosilanes were explained by the adsorption of methyl group on the silicon sites and by the surface diffusion of nearby Cl and H. The proposed reaction mechanism explains the formation of all silanes during the reaction and also during the TPD process.

구리 촉매를 이용하여 실리콘으로부터 기체상태의 methylchlorosilanes을 직접 생성하는 공정이 Rochow에 의해 제시되었고 이 후로 직접 생산 반응에 관하여 많은 연구가 진행되어 오고 있다. 직접 반응 촉매로서의 구리 외에 조촉매들을 첨가함으로서 반응의 활성을 증가시키고, 주 생산물인 DMDC 로의 선택도를 증가시키는 연구도 많이 보고되었다. 하지만 반응 기구에 있어서는 DMDC 의 생성을 설명하는 연구 외에 부산물로 함께 생성되는 여러 종류의 methylchlorosilanes 들의 생성과정을 설명하는 연구는 없는 실정이다. 그래서 본 연구에서는 실리콘 표면에 존재하는 것으로 보여지는 실리콘 활성점인 $=SlCl_2$와 $=Si(CH_3)Cl$의 존재를 제시하고 이 활성점 들에 메틸, 염소 및 수소가 첨가되어 methylchlorosilanes이 생성된다고 간주하였다. Methyl chloride ($CH_3Cl$)의 해리 흡착으로 인한 메틸-실리콘 결합의 생성과 해리 흡착한 후 표면에 존재하여 표면 이동을 하는 것으로 간주되는 Cl와 H을 이용하여 각 silanes 의 생성 경로를 제시하였다. 제시된 각 silanes 들의 생성 경로는 반응 결과 생성된 각 silanes의 종류뿐만 아니라 TPD 과정에서 생성되는 silanes 종류의 생성도 정확하게 설명해 주고 있다.

Keywords

References

  1. Rochow, E. G., "The Direct Synthesis of Organosilicon Compounds," J. Am. Chem. Soc., 67, 963(1945). https://doi.org/10.1021/ja01222a026
  2. Andrianov, K. A., Zhdanov, A. A. and Golubtsov, S. A., "Synthesis of Dimethyldichlorosilanes," Uspekhi Khim., 18, 145(1945).
  3. Wessel, T. J. and Rethwisch, D. G., "Activation of CuSi and CuZn- SnSi Contact Masses fot the Direct Synthesis of Methylchlorosilanes," React. Kinet. Catal. Lett., 58, 7-12(1996). https://doi.org/10.1007/BF02071098
  4. Gordon, A. D., Hinch, B. J. and Strongin, D. R., "Effects of Individual Promoters on the Direct Synthesis of Methylchlorosilanes," J. Catal., 266, 291-298(2009). https://doi.org/10.1016/j.jcat.2009.06.026
  5. Enrich, E., Born, D., Mendau-Richter, D. and Lieske, H., "Interaction of Alkali Salt Promoters and Silicon Impurities in Rochow Contacy Massesss," Appl. Organometallic Chem., 12, 257-264(1998). https://doi.org/10.1002/(SICI)1099-0739(199804)12:4<257::AID-AOC703>3.0.CO;2-5
  6. Gordon, A. D. and Strongin, D. R., "Effect of Individual Promoters on the Direct Synthesis of Methylchlorosilanes," J. Catal., 266, 291(2009). https://doi.org/10.1016/j.jcat.2009.06.026
  7. Kim, J. P. and Rethwisch, D. G., "Reaction Kinetics fot thr Direct Synthesis of Methylchlorosilanes," 134, 168(1992).
  8. Zhang, Y., Li, J., Liu, H., Ji, Y., Zhong, Z. and Su, F., "Promoting Effect of $In_2O_3$ on CuO for the RoChow Reaction: The Formation of P-N junctions at the Hetero-Interfaces," J. Catal., 348, 110-124 (2017). https://doi.org/10.1016/j.jcat.2016.11.039
  9. Zhang, Y,, Li, J., Liu, H., Ji, Y., Zhong, Z. and Su, F., "Hierarchical Zinc-copper Oxide Hollow Microspheres as Active Rochow Reaction Catalysts: The Formation and Effect of Charge Transferable Interfaces," J. Catal., 348, 233-245(2017). https://doi.org/10.1016/j.jcat.2017.02.030
  10. Zu, S., Ji, Y., Li, J., Jin, Z., Jia, L. and Gu, X., "Novel Leaflike Cu-O-Sn Nanosheet as Highly Efficient Catalysts," J. Catal., 337, 1-13(2016). https://doi.org/10.1016/j.jcat.2016.01.009
  11. Bazant, V., "On the Mechanism of the Direct Synthesis of Organohalogensilanes," Pure Appl. Chem., 19, 473(1969). https://doi.org/10.1351/pac196919030473
  12. Voorhoeve, R. J. H., "Organosilanes: Precursors to Silicones," Elsevier, New York(1967).
  13. Kim, J. P., "TPD Study for the Direct Synthesis of Methylchlorosilanes," Korean J. Chem. Eng., 12, 454(1995). https://doi.org/10.1007/BF02705810
  14. Hurd, D. T. and Rochow, E. G., "On the Mechanism of the Reaction between Methyl Chloride and Silicon-Copper," J. Am. Chem. Soc., 67, 1057(1945). https://doi.org/10.1021/ja01223a007