Methanol is an important basic raw material for the chemical industry and it has many applications in organic synthesis, dyes, medicines, pesticides, etc. Methanol, which is chemically mass-produced from coal gasification and natural gas, is a feed ingredient of C1 chemical industry and organic chemical industry.
Low-pressure methanol synthesis using copper-based catalysts is widely used worldwide in the production of methanol by coal gasification. Since the methanol obtained from this process contains water and a mixture of various organic substances, it must be purified for the usage as a raw material for the organic synthesis industry. Distillation is the most matured separation process, which is widely used for the purification of methanol.
Ro Jin Hyok, a researcher at the Faculty of Chemical Engineering, has simulated a methanol distillation process for obtaining high-purity methanol from crude methanol produced from coal gasification, and investigated the influence of some factors on its purity.
The factors include the rate of extracted water in the pre-distillation column, and the reflux ratio, the amount of distillate and the temperature of feed in the main distillation column.
The results show that the optimum conditions for the process operation are as follows. The rate of extracted water in the pre-distillation column is 3 500kg/h and the reflux ratio, the rate of distillate and the feed temperature are 1.1, 17 000kg/h and 69℃, respectively, in the main distillation column.
Under these conditions, the purity of methanol is 99.93% and the recovery rate is over 98.9%.