The relationship between white carbon black and trichlorosilane
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Hello, guys! I have a question: Can trichlorosilane be used to produce silica fume? What is the relationship between silica and trichlorosilane? Thank you! ! !
Silica is generally produced from silicon tetrachloride, as it is a troublesome by-product in the production of polysilicon
First question: Trichlorosilane cannot be used to produce silica gel; if you are referring to the process of producing trichlorosilane itself, then it is possible. Please look at the second question. The second question is: the relationship between silica and trichlorosilane. During the production of trichlorosilane, a certain amount of silicon tetrachloride is produced as a by-product. Handling this by-product, silicon tetrachloride, has always been a difficult problem; that’s why the method of using gaseous silicon tetrachloride for the production of silica was developed.
At present, in China, the by-product of trichlorosilane production, namely silicon tetrachloride, seems to have no other uses aside from being reduced back to trichlorosilane through hydrogenation or being used to produce fumed silica (of course, this is because I haven’t heard of any other uses). However, the conversion rate of silicon tetrachloride into trichlorosilane via hydrogenation is very low, and as a result, silicon tetrachloride becomes a bottleneck that hinders the large-scale production of trichlorosilane and polysilicon
Evonik (formerly Degussa)’s factory in Germany uses the vapor-phase process to produce silica, which is very expensive; however, this product does not have the same wide range of applications as silica produced by the precipitation method. If all silicon tetrachloride in the country were used to produce silica, there would be an overcapacity.