Patent ID: 8535488

Claim:
A method for a purification of trichlorosilane, the method comprising: performing a pretreatment for separating a chlorosilane mixture including trichlorosilane and tetrachlorosilane as a main ingredient from reaction products of a trichlorosilane production reaction by distillation; performing a first purification for separating the chlorosilane mixture separated by the pretreatment into a first top stream including a mixture of trace impurities and trichlorosilane, and a first bottom stream including tetrachlorosilane as a main ingredient; performing a second purification for separating the first top stream into a second top stream including a mixture of trace impurities having a low boiling point and trichlorosilane, and a second bottom stream including a mixture of trace impurities having a high boiling point and trichlorosilane; and performing a third purification for separating the second bottom stream into a third top stream including trichlorosilane as a main ingredient, and a third bottom stream including a mixture of trace impurities having a high boiling point and trichlorosilane, wherein the performing of the third purification is carried out under pressure conditions higher than those of the performing of the second purification, and a heat exchange is generated between the second bottom stream and the third top stream, and wherein the second bottom stream has a temperature of 40 to 120° C., and the third top stream has a temperature of 60 to 250° C.