微波协同氧化锆@碳纳米管强化果糖制 5-羟甲基糠醛

Catalytic conversion of saccharides is a promising way for the production of biomass-based fuel and high value-added chemical, and the utilization of microwave energy can make this process more commercially viable. In this paper, the efficient decomposition for fructose to 5-hydroxymethylfurfural (5-HMF) catalyzed over carbon nanotube-supported zirconia [ZrO₂/MWCNTs(C)] as a microwave response catalyst under microwave irradiation was investigated. Firstly, hydrothermal synthesis method was used to synthetize ZrO₂@MWCNTs(C) catalysts with high performance and then, they were characterized. Moreover, the effects of catalyst dosage, fructose concentration, reaction temperature and reaction time for the yield of 5-HMF were further investigated and lastly, by adjusting the participation of each component for composite catalyst during reaction, the microwave strengthening mechanism was revealed. Under a mild MW condition (at 120℃, atmospheric pressure), high 5-HMF yield about 74% after 10min reaction time was achieved which was significantly higher than that obtained under the conventional heating about 31%. With the optimum dosage of ZrO₂60/CNTs (50%), about 98% fructose conversion and about 92% 5-HMF yield could be achieved with microwave irradiation at 140℃ and atmospheric pressure for 10min. By exploring the coupling matching relation between the absorption performance of the supporting and the catalytic performance of the active site, the strengthening mechanism of the microwave synergistic catalytic process was revealed, which may be attributed to the combination of selective heating for carbon supporting and the active site of zirconia.