Ex-LDH-Based Catalysts for CO2 Conversion to Methanol and Dimethyl Ether

Catalysts

Elisabetta Rombi¹  MariaGiorgia Cutrufello¹  Luciano Atzori¹  Alberto Pettinau²  Mauro Mureddu²  Sarah Lai²  Francesca Ferrara² 

[1] Department of Chemical and Geological Sciences, University of Cagliari, 09042 Monserrato, Italy;Sotacarbo S.p.A.—Grande Miniera di Serbariu, SS 126, 09013 Carbonia, Italy;

关键词: CO₂ hydrogenation;    methanol synthesis;    DME synthesis;    ex-LDH;    bifunctional catalysts;   

DOI  :  10.3390/catal11050615

来源: DOAJ

【 摘 要 】

CO₂-derived methanol and dimethyl ether can play a very important role as fuels, energy carriers, and bulk chemicals. Methanol production from CO₂ and renewable hydrogen is considered to be one of the most promising pathways to alleviate global warming. In turn, methanol could be subsequently dehydrated into DME; alternatively, one-step CO₂ conversion to DME can be obtained by hydrogenation on bifunctional catalysts. In this light, four oxide catalysts with the same Cu and Zn content (Cu/Zn molar ratio = 2) were synthesized by calcining the corresponding CuZnAl LDH systems modified with Zr and/or Ce. The fresh ex-LDH catalysts were characterized in terms of composition, texture, structure, surface acidity and basicity, and reducibility. Structural and acid–base properties were also studied on H₂-treated samples, on which specific metal surface area and dispersion of metallic Cu were determined as well. After in situ H₂ treatment, the ex-LDH systems were tested as catalysts for the hydrogenation of CO₂ to methanol at 250 °C and 3.0 MPa. In the same experimental conditions, CO₂ conversion into dimethyl ether was studied on bifunctional catalysts obtained by physically mixing the ex-LDH hydrogenation catalysts with acid ferrierite or ZSM-5 zeolites. For both processes, the effect of the Al/Zr/Ce ratio on the products distribution was investigated.

【 授权许可】

Unknown