Temperature controlled phase inversion separation method of silicon tetrachloride and trichlorosilane in ionic liquid

The invention discloses a method for realizing high-efficiency quick separation of silicon tetrachloride and trichlorosilane by virtue of an ionic liquid in a temperature controlled phase inversion way. The method comprises the following steps: adding mixed chlorosilanes in different mass ratios to the ionic liquid at a lower temperature according to the difference of the solubilities of the ionic liquids to silicon tetrachloride and trichlorosilane at different temperatures, so that the chlorosilanes are thoroughly dissolved and distributed in the ionic liquid, and standing to form upper and lower two layers; separating the two layers of liquid phases from each other, and then evaporating and condensing the two liquid phase layers at different temperatures, respectively, to separate and recover single-component high-purity chlorosilanes. The method provided by the invention is capable of effectively solving the technical problem of silicon tetrachloride-trichlorosilane separation of a polycrystalline silicon enterprise; the method is simple and easy to implement; and the method has the advantages of mild operational conditions, closed-loop circulation, no pollution, low investment and low cost.