Review of Sustainable Production of Biomass-Based Amines Using Advanced Heterogeneous Nanocatalysis: Recent Trends and Future Perspectives

Abstract

Abstract Biomass-based amines are renewable precursors with versatile applications in pharma, agrochemical, food additive, lubricant, and polymer industries. Metal-based heterogeneous nanocatalysts have gained paramount importance for the synthesis of renewable amines due to their unique surface nanochemistry, tunable morphology, and cost-effectiveness, as well as their inherent acid-redox synergistic sites. The catalyst’s acid sites play a crucial role in C–N bond formation to generate reactive intermediates, whereas the redox sites accelerate the dissociative adsorption of hydrogen and the subsequent hydrogenation of intermediates to the targeted amines. This review focuses on the synthesis of renewable amines from nonedible lignocellulose-derived platform molecules, such as furfural (FAL)/its alcohol, 5-hydroxymethylfurfural (5-HMF), levulinic acid (LA)/its esters, and vanillin, using various metal-based heterogeneous nanocatalysts. It provides a comprehensive discussion on the fundamental aspects of reagents’ activation, nanosize-dependent active-site design, structure–activity correlations, and mechanistic insights into the desirable functional renewable amines. Particular emphasis is placed on catalytic reductive amination and tandem C–N coupling strategies, with a critical evaluation of hydrogen adsorption/activation/spillover on the catalyst surfaces. Finally, it concludes with future perspectives for engineering next-generation heterogeneous catalysts for biomass valorization, while highlighting the catalytic production of novel bio-amines for the sustainable pharmaceutical industry, without relying on fossil-derived chemicals.