Scale-up of microwave assisted flow processes for fine chemical synthesis

Monomode microwave heating has been applied in flow processes for the production of fine chemicals. Tubular reactors with diameters in milimeter scale, i.e. milli-reactors have been used to minimize penetration depth limitation of the microwaves. This work demonstrates two numbering-up approaches to improve the productivity of microwave assisted flow processing. Multiplication of microwave cavities in series improved the production rate by 3.5 fold as compared to one single cavity. Multiplication of tubular reactor channels in parallel provided increased troughput (6.6 fold). A near-isothermal operation was achieved in both approaches by cooling with a microwave transparent coolant (toluene)