Safely scaling hazardous chemistry through continuous flow technology

Highly reactive compounds in chemical production are both a blessing and a curse, as they allow fast and efficient conversions, but in the same time severely challenge reaction control, safety and equipment, to the point that some of these reactions cannot be conducted via conventional processing methods. Slowly but steadily, continuous flow technology is earning its place in the chemical industry as a technique for process intensification due to its superior reaction control. More and more, these advantages are applied to conduct hazardous chemistry, with its hazards well contained and controlled within a closed microreactor system. The possibility for on-site and on-demand synthesis of reactive intermediates coupled to direct conversion to stable end products avoids storage of and exposure to these harmful compounds. The focus on safety does however not imply that selectivity and throughput are secondary criteria. On the contrary, a shift to more ambitious territory is visible, where integration of hazardous chemistry and scalability via continuous flow technology is becoming industrial practice. The modularity of continuous flow systems enables a straightforward and rapid upscaling with guaranteed safety and without the need for time-consuming re-optimisation. Recent publications on continuous flow possibilities of hazardous chemistry on scale will be discussed, followed by an experimental study for the generation and consumption of labile acid chlorides in situ