Trihalosilane refining method

A trihalosilane refining method, comprising:

• introducing a feed containing a trihalosilane into a divided wall distillation column having a divided wall, which has a length of at least 30% with respect to a total theoretical plate number thereof, installed therein;
• and
• introducing an effluent flowing out from the divided wall distillation column into a first distillation column,
• wherein the divided wall distillation column comprises an upper column region, a preliminary separation region, a main separation region and a lower column region, and has an inlet port installed therein to introduce the feed containing a trihalosilane into the preliminary separation region, a first outlet port, a second outlet port and a third outlet port,
• wherein the effluent flowing out through the second outlet port is introduced into the 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.