Lignin is a macro polymer with aromatic structure and is a highly promising renewable carbon source for valuable chemicals and energy. It is available in huge quantities as a by-product from the paper & pulp industry and 2G ethanol industry. Valorization of lignin into useful chemicals can play a vital role in overcoming the demand of diverse chemicals being produced from petroleum feedstock. In the present study, we have examined the oxidative conversion of prot lignin in the presence of Cu/γ-Al₂O₃, Mn/γ-Al₂O₃, and Cu-Mn/γ-Al₂O₃ in water and ethanol-water co-solvent mixture. In water, maximum bio-oil yield of 24.0 wt.% was noticed with Cu/γ-Al₂O₃. In the case of ethanol-water (50/50) (wt/wt) co-solvent mixture, the maximum bio-oil yield of 74.3 wt.% was obtained with Cu/γ-Al₂O₃, catalyst. The bio-oil was analysed by GC-MS, ¹H-NMR, and FT-IR analyses. The GC-MS compounds were grouped as phenolic (G-, H-, and S-type), heterocyclic, acidic, and other type compounds. Among all the catalysts, Cu/γ-Al₂O₃ showed the maximum amount of phenolics (84.2%) using 25/75 (wt/wt) ethanol-water solvent. In the case of water as reaction medium, the non-catalytic and catalytic oxidation of lignin showed the maximum selectivity towards acetosyringone with area percentage as 42.0% and 34.4% respectively. In addition, the formation of vanillin (20.7%) was observed in the presence of Cu/γ-Al₂O₃ using water.

木质素是具有芳族结构的大分子聚合物，是极有价值的可再生碳源，可用于有价值的化学物质和能源。它是造纸和纸浆工业以及2G乙醇工业的副产品，有大量供应。将木质素转化为有用的化学物质可在克服由石油原料生产的多种化学物质的需求方面发挥至关重要的作用。在本研究中，我们已在Cu的存在检查PROT氧化转化木质素/γ-Al系₂ ö ₃，锰/γ-Al系₂ ö ₃，和铜锰/γ-Al系₂ ö ₃在水中，并乙醇-水共溶剂混合物。在水中，最大的24.0重量％的生物油产量随铜/γ-Al系注意到₂ ö₃。在乙醇-水（50/50）（重量/重量）助溶剂混合物中，74.3％（重量）的最大生物油产率的情况下，用铜/γ-Al系获得的₂ ö ₃，催化剂。通过GC-MS，¹ H-NMR和FT-IR分析来分析生物油。GC-MS化合物分为酚类（G型，H型和S型），杂环，酸性和其他类型的化合物。在所有的催化剂，铜/γ-Al系₂ ö ₃使用25/75（wt / wt）乙醇-水溶剂显示最大酚含量（84.2％）。在水作为反应介质的情况下，木质素的非催化和催化氧化显示出对乙酰丁香酮的最大选择性，面积百分比分别为42.0％和34.4％。另外，在铜/γ-Al的存在下观察到香草醛（20.7％）的形成₂ ö ₃使用水。