Recent developments in microwave-assisted thermal conversion of biomass for fuels and chemicals

Increasing energy demand coupled with greater consumer awareness of sustainability in meeting that demand has made the need to find renewable alternatives to fossil-derived products more pressing today than it has ever been. Biomass has long been identified as the renewable resource best suited for being converted through various processing techniques into products that can supplement and ultimately replace fossil derived fuels and chemicals. The thermal conversion of biomass to renewable fuels and chemicals has been the subject of research for several decades with some commercial success. One of the limitations of current thermal biomass conversion platforms is process efficiency due to the nature of heat transfer. Microwave-assisted thermal conversion of biomass has received significant attention in recent years as it is capable of improving the process efficiency and product quality. The objective of this work was to perform a review of the recent developments in the microwave-assisted thermal conversion of biomass for fuels and chemicals. Specifically, we review the fundamentals of microwave dielectric heating and microwave-matter interactions in light of the factors that influence this interaction; the studies related to the use of microwave dielectric heating in the pyrolysis of biomass, with emphasis on the advances made in recent years; and the challenges that affect the commercial deployment of pyrolysis of microwave assisted biomass and future direction. The available literature shows significant progress has been made in understanding the microwave-assisted thermal conversion of biomass. However, additional efforts and research are still needed to fully translate the technology from research to commercialization.