The chlorosilane disproportionation method was developed by U.S. Union Carbide Corporation (UCC Corporation of the United States).

This process is mainly for the preparation method of silane, which uses silicon tetrachloride to hydrogenate to form trichlorosilane. Then, trichlorosilane is disproportionated to form dichlorodihydrosilane, and dichlorodihydrosilane is disproportionated to form silane. . The reaction equation is:

The main features of the process:

1. Disproportionation reaction is carried out in a tower reactor, which is very suitable for large-scale production, high production efficiency, low power consumption and low cost.
2. The whole system is closed loop, with few discharges, which is environmentally friendly and has high material utilization rate;
3. The reaction product and silane are easily separated, and high purity silane (9-11N) can be obtained.
4. The remaining silicon hydride remaining in the silane rectification can be returned to the disproportionation tower for re-reaction;
5. The reaction conditions are mild, the energy consumption is low, and the operation and control are easy;
6. It can produce a variety of silicon source materials such as silane, silicon tetrachloride, dichlorodihydrosilane, etc., and can easily match the proportion of products.

This method has the highest purity of silane, and pyrolysis can obtain polycrystalline silicon with a purity of up to 9-11N. This method has achieved a production level of 1,000 tons. The world's largest silane manufacturer, REC (formerly Asimi), used this method to prepare silane gas.