Theoretical Study For Disproportionation Of Methyltrichlorosilane Catalyzed By Different Cluster Model ZSM-5 Zeolite Catalyst

Organic silicon material is silicone high-performance materials,its mainly inorganic structure chain,with organic groups as side chain,it possesses the advantages of the inorganic and organic compounds and its top priority was to monomer dimethyldichlorosilance(referred to M2).As the necessity of the market of M2 was boosting,the direct synthesis method products by-product,namely,more and more methyltrichlorosilane(referred to M1)and trimethylchlorosilane(referred to M3).So it received much concern to how to make wasteful methyltrichlorosilane and trimethylchlorosilane to dimethyldichlorosilance profitable.As researches show,it is much catalytic effect for disproportionation of methyltrichlorosilane catalyzed by ZSM-5 and AlCl3.The theoretical study about disproportionation of methyltrichlorosilane is seldom domestic and overseas at present.Especially,it is much less about the theoretical study about disproportionation of methyltrichlorosilane catalyzed different cluster model ZSM-5zeolite catalyst.So the research emphasis in this is discussing that the mechanism of the disproportionated reaction of dimethyldichlorosilance catalyzed by cluster model ZSM-5 zeolite catalysts and catalytic activity of different cluster model ZSM-5 zeolite catalysts catalyzing the disporportionated reaction of dimethyldichlorosilane with theoretical calculation methods.This article selects 3T,4T and 6T three different cluster model ZSM-5 zeolite catalysts,with Quantum Chemistry Density Functional Theory Mean,respectively exploring the mechanism of the disproportionated reaction of dimehtydichlorosilane catalyzed by 3T cluster NaAlCl4/ZSM-5?4T cluster NaAlCl4/ZSM-5?6T cluster NaAlCl4/ZSM-5 and modified 4T cluster NaAlCl4/(AlCl2)+-ZSM-5 catalyst.Conclusions are as follows:(1)Disproportionation of dimethyldichlorosilance prepared with methyltrichlorosilane and trimethylchlorosilane catalyzed by 3T cluster NaAlCl4/ZSM-5 catalyst was calculated through B3LYP/6-311G++(3df,2pd)approaches.The rate-determining step is the second step.But it is high that the activation energy is 109.28 kJ·mol-1.The reaction can conduct.(2)Disproportionation of dimethyldichlorosilance prepared with methyltrichlorosilane and trimethylchlorosilane catalyzed by 4T cluster NaAlCl4/ZSM-5 catalyst was calculated through B3LYP/6-311G++(3df,2pd)approaches.The rate-determining step is the second step.The activation energy of the first and second step is 53.98 and 106.89 kJ·mol-1respectively.The reaction is easy to conduct.(3)Disproportionation of dimethyldichlorosilance prepared with methyltrichlorosilane and trimethylchlorosilane catalyzed by 6T cluster NaAlCl4/ZSM-5 catalyst was calculated through B3LYP/6-311G++(3df,2pd)approaches.The rate-determining step is the second step.The reaction can conduct,but the speed is slow.(4)Disproportionation of dimethyldichlorosilance prepared with methyltrichlorosilane and trimethylchlorosilane catalyzed by modified 4T cluster NaAlCl4/(AlCl2)+-ZSM-5 catalyst was calculated through B3LYP/6-311G++(3df,2pd)approaches.The rate-determining step is the second step.Because of the activation energy for 97.89 kJ · mol-1,the reaction is easy to conduct.Indicting that catalytic effect modified by(-AlCl2)is good.The reasons maybe that cloud density from acid site(-AlCl2)of the disproportionated reaction catalyzed by the modified catalyst 4T cluster NaAlCl4/(AlCl2)+-ZSM-5.In summery: these four catalysts of 3T cluster NaAl Cl4/ZSM-5,4T cluster NaAlCl4/ZSM-5,6T cluster NaAlCl4/ZSM-5 and4 T cluster NaAlCl4/(AlCl2)+-ZSM-5 have different catalytic effects for the disproportionated reaction of dimethyldichlorosilance prepared.And the catalytic activity order of these four catalysts is 4T cluster NaAlCl4/(Al Cl2)+-ZSM-5>4T cluster NaAlCl4/ZSM-5>3T cluster NaAl Cl4/ZSM-5>6T cluster NaAlCl4/ZSM-5.The above calculation results can provide theoretical basis data for subsequent nuclear shell and core double shell catalyst research.