Trihalosilane refining method

A trihalosilane refining method, comprising:

• introducing a feed containing a trihalosilane through an inlet port of a divided wall distillation column, which has an upper column region, a preliminary separation region, a main separation region and a lower column region formed therein and comprises the inlet port installed to introduce the feed containing the trihalosilane into the preliminary separation region, a first outlet port, a second outlet port and a third outlet port;
• and
• introducing an effluent, which flows out through the second outlet port formed at the 1/9 to 8/9 section of the divided wall section of the main separation region, into a first distillation column,
• wherein the second outlet port or the effluent flowing out through the second outlet port is maintained at a temperature of 86.4° C. to 116.4° C., and
• wherein the first distillation column is maintained at an operating pressure of −0.6 Kg/sqcmG to 9.0 Kg/sqcmG and an operating temperature of 37° C. to 145° C.