Miao Zuo,Xinyu Wang,Wenlong Jia,Yanzhong Zhu,Xianhai Zeng,Lu Lin
As one of the essential building blocks for bio-chemicals and bio-fuels, the 5-Hydroxymethylfurfural (HMF) production is still challenging in a green and cheap way. This work developed a bio-derived aqueous-natural deep eutectic solvent (A-NADES) to synthesize HMF using α-Al 2 O 3 or Al(OH) 3 as robust catalysts, obtaining high yields of 67.1% and 63.6% HMF from glucose under mild reaction reactions, respectively. Different kinds of starches and starchy food waste also exhibited high conversion efficiency in the A-NADES system. The mechanistic study indicated that the in-situ formed Al (III) site of α-Al 2 O 3 during the reaction was critical for converting glucose-based carbohydrates. A-NADES could be effectively reused six times with a more convenient direct reuse method without significant activity loss. This study suggested a novel A-NADES reaction media in the synergistic reaction with robust aluminum-based catalysts for HMF synthesis, and proposed a novel process of food waste utilization in green solvents.
Hongcai Su,Ekkachai Kanchanatip,Defeng Wang,Haidan Zhang,Antoni,Ishrat Mubeen,Zhicheng Huang,Mi Yan
Ni/Al 2 O 3 catalyst is the one of promising catalysts for enhancing H 2 production from supercritical water gasification (SCWG) of biomass. However, due to carbon deposition , the deactivation of Ni/Al 2 O 3 catalyst is still a serious issue. In this work, the effects of lanthanum (La) as promoter on the properties and catalytic performance of Ni/Al 2 O 3 in SCWG of food waste were investigated. La promoted Ni/Al 2 O 3 catalysts with different La loading content (3–15 wt%) were prepared via impregnation method. The catalysts were characterized using XRD , SEM, BET techniques. The SCWG experiments were carried out in a Hastelloy batch reactor in the operating temperature range of 420–480 °C, and evaluated based on H 2 production. The stability of the catalysts was assessed by the amount of carbon deposition on catalyst surface and their catalytic activity after reuse cycles. The results showed that 9 wt% La promoter is the optimal loading as Ni/9La–Al 2 O 3 catalyst performed best performance with the highest H 2 yield of 8.03 mol/kg, and H 2 mole fraction of 42.46% at 480 °C. La promoted Ni/Al 2 O 3 catalysts have better anti-carbon deposition properties than bare Ni/Al 2 O 3 catalyst, resulting in better gasification efficiency after reuse cycles. Ni/9La–Al 2 O 3 catalyst showed high catalytic activity in SCWG of food waste and had good stability as it was still active for enhancing H 2 production when used in SCWG for the third time, which indicated that La promoted Ni/Al 2 O 3 catalysts are potential additive to improve the SCWG of food waste.