Low-carbon Alcohols from Syn-gas Developed by CAS Passed Review and Assessment

The CAS Institute of Coal Chemistry (ICC) in collaboration with the Shenhua Coal-to-Oil Chemical Co., Ltd. have implemented the commercial sideline tests of a 10 kt/a unit for synthesis of low-carbon alcohols from coal-based syngas and this fi rst in China unit has passed the 1000-hours-long high duty check tests.

This sideline alcohol synthesis unit is situated at the Shenhua’s Baotou Coal Chemical Company. The test results have revealed that the process regime of this unit is mild with high yield of low-carbon alcohols. Under the relatively moderate reaction conditions covering a reaction temperature of 230—260 ℃ and a reaction pressure of 6.0 MPa, the CO conversion rate can reach over 85%, with the low-carbon alcohol selectivity exceeding 60%. This unit can produce 15 tons of low-carbon alcohols a day, and the raw products can be further separated into the industrial C1—C3chemical alcohols and C4+ alcohols used as the fuel additive. These test results are better than those referred to in the overseas public information.

It is learned that the new technology for synthesis of lowcarbon alcohols adopts the Cu-based catalyst which was independently developed by ICC with such advantages as low price, high activity, high mechanical strength, absence of environmental pollution, low preparation cost, good repeatability of performance, with its cost and manufacture process being comparable with the methanol synthesis catalyst. The technology for separation of raw mixed alcohols adopts the fl ow diagram developed mainly by the Shenhua Group, which consists of “nine columns plus one vessel”, viz.: nine recti fi cation columns and a membrane separation vessel to achieve recti fi cation process in combination with extraction and membrane separation to successfully obtain high-purity methanol, ethanol, propanol, butanol and other chemical products.