Construction of a highly active and water-resistant Ni-based catalyst for the HDO reaction of phenol†
Abstract
Aqueous-phase hydrodeoxygenation (HDO) of biomass-derived phenolic compounds is considered as one of the most promising ways to convert biomass into fuels and value-added chemicals. The aim of this study is to develop highly active and water-resistant catalysts with a low price. For this purpose, with cheap transition Ni as the active phase, supported Ni@C/MxOy(x) and Ni@C/Al2O3(5)-glucose catalysts (MxOy stands for ZrO2, CeO2, TiO2 or Al2O3 and x represents Ni loading) were prepared from Ni-MOF-74/MxOy (x). The prepared catalysts were characterized by TG, H2-TPR, XRD, BET, HRTEM, XPS and NH3-TPD. The effect of the support, Ni loading and glucose incorporation on the HDO performance of phenol was investigated. The results showed that the Ni@C/Al2O3(5) catalyst with Al2O3 as the support and a low Ni loading of 5% exhibited the best HDO activity. The superior performance with such a low Ni loading greatly reduced the cost of the catalysts. Furthermore, the total yield of the deoxygenated product over Ni@C/Al2O3(5) was increased by 22.3% after the incorporation of glucose when the molar ratio of phenol/water was 1 : 1.25. In addition, the fixed-bed reactor experiment revealed that the HDO performance of Ni@C/Al2O3(5)-glucose almost remained stable during 48 h on-stream operation, indicating its excellent stability.