MOF-derived CoCeOx nanocomposite catalyst with enhanced anti-coking property for ethanol reforming with CO2

Abstract

Up to date, to design the efficient catalysts for CO2 reforming with ethanol is of great challenge due to the severe coke deposition. In this work, MOF derived CoCeOx nanocomposite (CoCe-MOF) with outstanding performance for ethanol dry reforming was successfully prepared. Indeed, the experimental results revealed that ethanol conversion was 97% with a H2/CO ratio of ca.1 and negligible acetone formation (0.4 mol%) at 550 °C which was better than that of Co3O4/CeO2 synthesized by impregnation technique. Moreover, no obvious deactivation was observed even after 40 h time-on-stream tests for CoCe-MOF catalyst. Interestingly, ethanol conversion over CoCe-MOF slightly decreased from 99% to 96% while the value over Co3O4/CeO2 sample remarkably declined from 90% to 79% as well as the increase of byproduct formation (acetone from 1.1 mol% to 1.9 mol%). Particularly, the relationship between catalytic performance and morphology structure were investigated in detail by a series of characterization technique such as XRD, H2-TPR, BET, XPS, TEM, Raman etc. The results demonstrated that the uniform aliovalent incorporation of Co into CeO2 framework greatly improved the physicochemical features of the CoCe-MOF catalyst including the generation of more oxygen defects/surface oxygen species (14,5% of Ce3+ species), stronger Co-O-Ce interaction, lower temperature reducibility etc. Hence, these positive factors might explain its high activity and stability. Eventually, this study might provide a simple method to develop the high-performance catalysts for dry reforming process and other heterogeneous catalytic reactions.