Preparation of Ionic Liquids in Flow Chemistry: Advances and Perspectives

Recently, ionic liquids (ILs) have found use across a broad spectrum of applications, including explosives, propellant fuels, solvents, catalysts, pharmaceutics, and energy, leading to a growing demand that exceeds the capacity of conventional batch or semibatch processes. Flow chemistry, which employs channels or tubing to perform reactions continuously, has been demonstrated as a safe and effective method for synthesizing ILs. This paper offers a comprehensive overview of the preparation of ILs in flow chemistry. It begins with summarizing preparation strategies of ILs in flow chemistry and discussing the associated challenges. The subsequent section provides a detailed discussion of mass transfer and heat management within flow chemistry setups. Kinetic studies of alkylation reactions for the synthesis of representative ILs are summarized and analyzed. In addition, the quality characteristics of ILs produced using flow chemistry are emphasized.