New Catalysts Studies On The Catalytic Decomposition And Disproportionation Reactions And Mechanism Of Organosilicon High-boiling Residue

The paper is concerned with treating and reusing the high-boiling residue, which formed in the direct process for synthesis of methylchlorosilanes. High-boiling residue amount employ 5ï¼…in the amount of methylchlorosilanes. As they are difficult to be converted into commercially valuable methylchlorosilanes by simple methods, high-boiling residue used to be impossible of utilization very good because long-term storage was dangerous and they were easier eroding to tank. They were merely dumped into the sea that making the environment pollution. As the methylchlorosilanes produce scale enlarging, high-boiling residue utilization problems are seriously so that exploring a validly industrialization method is urgent.This paper based on the high-boiling residue cracking mechanism, employed ionic liquids and mesoporous molecular sieve MCM-41 immobilizing AlCl₃ as the high-boiling catalytic decomposition catalyst, adopted CHCl₃ as terminal reagent, and investigated its catalytic reactions under low pressure (≤0.3MPa). We primary studied employing hydrothermal method to synthesize MCM-41, grafting anhydrous AlCl₃ onto MCM-41, characterizing samples by XRD, FT-IR, TEM, SEM, ICP, N₂ adsorption/desorption, and TG technologies, and evaluating the catalytic activity for high-boiling residue decomposition. Amount of catalyst, reaction time, volume ratio of CHCl₃ with high-boiling residue, and amount of AlCl₃ loading on MCM-41 were investigated to find out the optimal reaction conditions. Results indicated that under the optimal reaction conditions, conversion of high-boiling residue and total yield of methylchloromonosilanes reaches 75ï¼…and 65ï¼…, respectively.The catalytic decomposition reaction of high-boiling residue was also studied using [trEtHAm] Cl-XAlCl₃ ionic liquid as catalyst. Effect of activated component, reaction time, and amount of catalyst on catalytic activity were investigated. When the mole ratio of CHCl₃: High-boiling residue:ILs is 1.5:1:1, X is 0.67, the catalytic decomposition reahed the best effect. The conversion of high-boiling residue and total yield of methylchloromonosilanes reaches 59.6ï¼…and 40.8ï¼…, respectively.In-situ FT-IR characterization technology was employed to study the catalytic cleavage of the Si-Si bonds mechanism. It may benefit for finding optimal methods and ways to utilize the high-boiling residue and make good economic, social and ecological benefits.