Direct Conversion of Syngas to Light Olefins over a ZnCrO x + H-SSZ-13 Bifunctional Catalyst

Yuxuan Huang; Hongfang Ma; Zhiqiang Xu; Weixin Qian; Haitao Zhang; Weiyong Ying

doi:10.1021/acsomega.1c00751

Direct Conversion of Syngas to Light Olefins over a ZnCrO _x + H-SSZ-13 Bifunctional Catalyst

ACS Omega. 2021 Apr 19;6(16):10953-10962. doi: 10.1021/acsomega.1c00751. eCollection 2021 Apr 27.

Authors

Yuxuan Huang¹, Hongfang Ma¹, Zhiqiang Xu¹, Weixin Qian¹, Haitao Zhang¹, Weiyong Ying¹

Affiliation

¹ Engineering Research Center of Large Scale Reactor Engineering and Technology, Ministry of Education, State Key Laboratory of Chemical Engineering, School of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China.

Abstract

In recent years, bifunctional catalysts for the syngas-to-olefins (STO) reaction via the oxide-zeolite (OX-ZEO) strategy has been intensively investigated. However, the bifunctional catalyst containing H-SSZ-13 with a 100% H⁺-exchanging degree for the STO reaction has not been developed because of the high selectivity to paraffin. Here, we report a ZnCrO _x + H-SSZ-13 bifunctional catalyst, which contains the submicron H-SSZ-13 with adequate acidic strength. Light olefins in hydrocarbon reached 70.8% at a CO conversion of 20.9% over the ZnCrO _x + H-SSZ-13(23S) bifunctional catalyst at 653 K, 1.0 MPa, and GHSV = 6000 mL·g^-1·h^-1 after 800 min of STO reaction. The effect of CO and H₂ on the C-C coupling was discussed by carrying out the methanol-to-olefins (MTO) reaction under a similar atmosphere as that of the STO reaction. H₂ and CO should play a more dominant role than the conventional hydrogen transfer reaction on the undesired high selectivity of paraffins. These findings provide new insight into the design of the bifunctional catalyst for the STO process via the OX-ZEO strategy.