Progress in high carbon efficiencysynthesis gas to long chain α-olefin

Recently, a new modified ruthenium-basedFischer-Tropsch (FTO) catalyst has been prepared by the research team ofLiangshu Zhong and Yuhan Sun at the Shanghai Institute of Advanced Studies ofthe Chinese Academy of Sciences (SIAS) to achieve high carbon efficiency directconversion of syngas to long-chain α-olefins.

The team developed an alkali metal modifiedruthenium-based catalyst and applied it to the direct conversion of synthesisgas to olefins by the FTO route, and the modified ruthenium-based catalystexhibited excellent catalytic performance. The modified ruthenium-basedcatalysts exhibited the lowest C₁ byproduct selectivity, thehighest total olefin selectivity and yield, and the olefin yield exceeded 50%compared with the catalytic systems studied so far for olefin production fromsyngas.

The experimental results show that theolefin selectivity can be as high as 80.1% at 45.8% CO conversion, of which74.5% olefins belong to C₅+ long-chain α-olefins, while the totalmethane and CO2 selectivity is less than 5%, reflecting the extremely highcarbon efficiency. It is worth mentioning that the catalyst is applicable toalmost all syngas obtained from carbon-containing sources.

Moreover, with this catalyst, the C₁ by-product selectivity is still less than 5% under close toindustrial reaction conditions. At the same time, the catalyst is stable andhas excellent prospects for industrial applications. This study shows that thetargeted regulation of product selectivity can be achieved through the precisemodulation of the chemical environment at the catalyst surface interface,providing a new solution to the key scientific problem of product selectivityregulation in syngas conversion.

Olefins include low carbon olefins and longchain α-olefins. Significant breakthroughs have been made in recent years inthe direct synthesis of olefins from syngas. However, in the catalytic systemsstudied so far, the selectivity of C₁ by-products in the productsis high, which reduces the carbon utilization efficiency and olefin yield ofthe reaction process. Under the background of "double carbon", it isurgent to develop new high carbon efficiency catalysts for direct synthesis gasto olefin conversion, which can significantly reduce C₁by-product selectivity, achieve high activity and high selectivity to obtainlong chain α-olefins, and achieve the purpose of energy saving, emissionreduction and efficiency increase.