Industrial wastes and natural mixed oxide materials were evaluated as inexpensive heterogeneous catalysts for catalytic hydrothermal liquefaction (HTL) of food wastes. Base MgO and ZSM-5 and mixture of MgO + ZSM-5 achieved bio-oil yields of 31.2, 35.5, and 40.6 wt% with higher heating values (HHVs) of 32.5–34.8 MJ kg^-1, respectively, which were much greater than those without the catalyst. Bio-oil characterization revealed that similar families of molecules were formed in the presence and absence of catalysts, implying that the main role of the catalyst is to promote rates of thermal reactions, leading to Bio-oil production. The improved catalytic HTL performance of the mixed metal oxides compared with single-metal oxides was attributed to the synergistic effects of base and acid sites present on catalyst surfaces. Maximum yield of aromatic hydrocarbon compounds (49%) observed in case of HTL with MgO + ZSM-5 mixture catalyst. The percent of energy recovered as bio-oil was strongly correlated with the base-to-acid site density ratio, providing an important performance predictor for catalyst HTL conversion of food waste to bioenergy.

工业废料和天然混合氧化物材料被评估为廉价的用于食物废料的催化水热液化（HTL）的非均相催化剂。基本的MgO和ZSM-5以及MgO + ZSM-5的混合物实现了31.2、35.5和40.6 wt％的生物油产率，较高的热值（HHV）为32.5–34.8 MJ kg ^-1分别比没有催化剂的大得多。生物油的表征表明，在有和没有催化剂的情况下，会形成相似的分子家族，这意味着催化剂的主要作用是促进热反应速率，从而导致生物油的产生。与单金属氧化物相比，混合金属氧化物的催化HTL性能有所提高，这归因于催化剂表面上存在的碱位和酸位的协同效应。在使用MgO + ZSM-5混合催化剂进行HTL的情况下，观察到芳烃化合物的最大收率（49％）。作为生物油回收的能量百分比与碱酸位点密度比密切相关，为将食物垃圾转化为生物能进行催化剂HTL转化提供了重要的性能指标。