1994 Fiscal Year Final Research Report Summary
Development of Direct Synthesis of Alkoxysilanes from Silica by Gas-Solid Reactions
Project/Area Number |
05555216
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Research Category |
Grant-in-Aid for Developmental Scientific Research (B)
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Allocation Type | Single-year Grants |
Research Field |
触媒・化学プロセス
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Research Institution | Tokyo Institute of Technology |
Principal Investigator |
ONO Yoshio Tokyo Institute of Technology, Faculty of Engineering, Professor, 工学部, 教授 (10016397)
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Co-Investigator(Kenkyū-buntansha) |
SUZUKI Eiichi Tokyo Institute of Technology, Faculty of Engineering, Associate professor, 工学部, 助教授 (90183417)
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Project Period (FY) |
1993 – 1994
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Keywords | Silica / Dialkylcarbonates / Alkoxysilanes |
Research Abstract |
In the reaction of silica with dimethyl carbonate to give tetramethoxysilane, the effect of physical properties of silica on the reaction rate of the silica was examined. The silica, which was obtained by drying colloidal silica at 150゚C,Was calcined at various temperatures. The silica sample, on which potassium hydroxide as a catalyst was supported by 5wt.%, was loaded in a fixed-bed flow reactor. After heated at 260゚C for 1 h under a helium stream, the sample was subjected to contact with dimethyl carbonate vapor at 260゚C.For the calcination temperatures of 400-600゚C,the rate was greater at the higher calcination temperatures, while it was smaller for the 700-900゚C calcinations. The reaction rate was not controlled by the pore distribution or surface area of silica sample. Generation of new reactive silica surface with the reaction proceeding was a determining factor of the rate. Silica was found to react also with diethyl carbonate to give tetraethoxysilane. The effect of reaction variables on the rate of silica consumption was examined. Hydrous titanium oxide was found to react with diethyl carbonate to yield tetraethoxytitanium. thus, using potassium hydroxide (5wt.%) as a catalyst, a 93% yield of tetraethoxytitanium was obtained at 230゚C in an autoclave.The effect of reaction temperature and the temperature of calcining the hydrous titanium oxide on the tetraethoxytitanium yield was examined.
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