Abstract:
A series of Zn
xCe
2-yZr
yO
4 metal oxides were synthesized by sol gel method, hydrothermal method and co-precipitation method respectively and characterized by XRD, BET, HRTEM, CO-TPD, Raman and XPS. The effects of the synthesis method on the morphology, grain size and oxygen vacancy concentration and the catalytic performance in syngas to low-carbon olefin reaction of the Zn
xCe
2-yZr
yO
4 catalysts were investigated. The results show that the shape, exposed crystal surface, grain size and surface oxygen vacancy concentration of Zn
xCe
2-yZr
yO
4 solid solution are strongly dependent on the synthesis method. Under the reaction conditions of 300 ℃ and 1.0 MPa, the dual-functional catalysts of Zn
xCe
2-yZr
yO
4/SAPO-34 prepared by sol-gel method have the highest low-carbon olefin (C
2-4=) selectivity (79.5%), while the selectivities of methane and CO
2 are only 5.5% and 10.7%, respectively. Here the direct conversion of syngas to low-carbon olefins are realized at low temperature and pressure and the formation of methane and CO
2 is greatly reduced.