Handling Solids in Microreactors for Continuous-Flow Synthetic Chemistry

Microchemical systems catalyze discovery and development of synthetic routes while realizing a more basic understanding of chemistry. Enhanced heat and mass transfer characteristics, safer synthesis of dangerous compounds, isolation of air- and moisture-sensitive chemistries, reduction of hazardous waste, optimized reaction conditions, and rapid experimentation add value to the technology by shortening product development life cycles. Multiphase synthetic chemistry often involves the use of solids, which take the form of products, by-products, reagents, and catalysts. Chemical syntheses forming inorganic salts are difficult to carry out because these solids can clog microchannels. Chemistry and engineering strategies for handling solids must therefore be developed in order to realize complex microchemical synthesis.

We investigate several strategies for handling solids in microchemical systems and apply basic principles to a model coupling chemistry that is widely employed in industry. Microreactor surface modification, reactor design fundamentals, and acoustic forces comprise approaches to overcome this challenge and enable continuous-flow synthesis. These and other results will be presented and discussed.