Continuous manufacturing offers an interesting toolbox for process intensification of API manufacturing processes. Flow Chemistry offers a wide range of interesting processing options beside the “classics” of micro reaction technology/flow chemistry, like fast exothermic reactions and hazardous chemistry. An optimization of mass and heat transfer can reduce the necessary processing times by a factor of up to 10. By addressing the specific needs of a chemical reaction by means of specific reactors, by-product formation can be significantly reduced.
The consequence of a reduced by-product formation leads to reduced work-up effort. Blocks of three to four synthesis steps can be often executed without separation and work–up. Shorter processing times, by a factor of up to 10, have been demonstrated. In one project the number of unit operations has been reduced from 18 to 9. The number of solvents for four key steps has been reduced from 14 kg solvent per kg of product, 2 of them chlorinated, to 7 kg solvent per kg of product, using only chlorine-free solvents. Sometimes these efficiency-increasing projects pay for themselves by the sheer reduction of working capital, since the number of materials in process can be dramatically reduced. Continuous Manufacturing enables a reduced variability of batches. Quality costs can be reduced by the use of PAT tools. Safety is increased by much smaller reactor volumes and a much better process control can be achieved. Hazardous reagents can be generated in situ and do not need to be stored. Microinnova offers the development of new process concepts by keeping the synthesis route.