Chapter 2: Role of Microwaves in Heterogeneous Catalysis

This chapter discusses solid-state catalytic reactions using the microwave heterogeneous microscopic thermal effect (MHMTE), and its positive effects in terms of chemical reactions examined from our research experience. In addition, the distribution of heat in solid catalysts during the generation of MHMTE is also explained using a coupled analysis of electromagnetic fields and heat transfer in computer simulations. On the other hand, it should be noted that there are ineffective chemical reactions despite the generation of MHMTE. The principle of the generation of hotspots (electric discharges and plasmas) in microwave chemistry will be described, as hotspot formation poses a peculiar problem for solid catalyst reactions when microwaves are used; the methods to suppress the occurrence of hotspots shall be discoursed.