Green Chemistry Concepts and Metrics for Solvent Selection
Green solvents reduce health, safety, and environmental hazards, which in turn contributes to lowering the negative impact of solvent use. A thorough analysis of previous attempts to characterise green solvents has been made, including defining principles and solvent selection guides. Considered aspects cover the production of solvents, their flammability and toxicity, and waste management. Methods of evaluating solvent performance are also important to demonstrate that green solvents are not inferior to more typical solvents. Tools to achieve this are explained, including linear solvation energy relationships. It has become apparent that industry requires new solvents to maintain current levels of performance when forced by regulation to curtail the use of conventional solvent options. Computational design of bespoke solvents is increasingly being practiced with the aim of finding replacements for the most hazardous but vital solvents used in chemistry. Several approaches to computational solvent design are explained in this chapter.