Journal of Research in Applied Chemistry

Authors: Depanker Kulkarni, Radhe Shyam Pandey, Farhan Iqbal

Abstract: Solvents play a central role in chemical synthesis, separation, and processing, yet they account for a major fraction of waste and environmental burden generated by the chemical and pharmaceutical industries. Conventional organic solvents are often volatile, toxic, flammable, and derived from non-renewable petrochemical resources. In recent years, the concept of sustainable solvents and green reaction media has gained significant attention as part of the broader framework of green chemistry. Sustainable solvents aim to reduce environmental impact while maintaining or improving reaction efficiency, selectivity, and safety. This review provides a comprehensive overview of the principles guiding solvent sustainability, classifications of green solvents, and recent developments in alternative reaction media such as water, supercritical fluids, ionic liquids, deep eutectic solvents, and bio-based solvents. The advantages and limitations of each solvent class are critically discussed with selected case studies from organic synthesis, catalysis, and industrial processes. In addition, solvent selection guides, life cycle assessment, and regulatory considerations are examined. The review also highlights current challenges, including cost, scalability, toxicity uncertainties, and recycling issues, along with future perspectives toward truly sustainable solvent systems. Although significant progress has been achieved, the transition from traditional solvents to greener alternatives remains an evolving process that requires interdisciplinary collaboration between chemists, engineers, and policymakers.

Keywords: Green chemistry; sustainable solvents; reaction media; bio-based solvents; ionic liquids; deep eutectic solvents