The role of green chemistry in the transformation of agro-industrial wastes for health and environment: a review

Green chemistry is defined as a set of principles that reduce or prevent the use or generation of hazardous substances during the design, production, and utilization of chemical products. The vision of such a paradigm shift in the chemical sciences is that the concept of being green is directly introduced to the molecular design process and is centered on atom economy and the prevention of waste. This review examines the principles of green chemistry in relation to agro-industrial waste valorization, with specific reference to the ecological and economic conditions of India, where approximately 350 million metric tons of annual agro-residues have become a source of serious environmental management issues, such as greenhouse gas emissions through open burning, leachate waste generation through landfills, and effects on the health of the population through poor disposal practices. The analysis summarizes the latest developments in nanotechnology-based catalytic systems, new solvent platforms (ionic liquids, deep eutectic solvents, and supercritical fluids), and integrated biorefineries, and critically reviews the scalability limitations and commercial feasibility. It also discusses more recent developments, such as systems based on nanotechnology, catalyst transformations (homogeneous, heterogeneous, and biocatalysts), and the creation of alternative solvents, such as ionic liquids, deep eutectic solvents, and supercritical fluids. The virtues of agri-industrial residues and biomass-based feeds are given particular attention in terms of their role in models of the circular economy and the generation of value-added chemicals, fuels, and materials. By illustrating how green chemistry can minimize the environmental footprint of traditional processes and create safer and more economically viable alternatives, this review makes it clear why green chemistry has become a revolution in the field of industrial practice. Lastly, the paper addresses contemporary issues of scalability, economic competitiveness, and regulatory integration and outlines opportunities that will make green chemistry the foundation of sustainable, resource-efficient, and environmentally responsible chemical companies.