Reaction engineering for process intensification of supercritical water biomass refining

Abstract Status reports from public and private organizations make a roadmap for achieving a bioeconomy for society. Biobased industries, based on renewable materials and energy, are still in development to supporting a decentralized production that can be an alternative to the well-supported centralized petrochemical production plants. The use of pressurized water has been proposed as an environmentally compatible process to integrate the depolymerization–reaction–separation of the biomass supported processes. Supercritical water is emerging as a solvent and reaction medium capable of providing selective processes while significantly reducing the reaction time, leading to the possibility of developing compact equipment for the use in biomass decentralized production plants. The main ways of biomass upgrading in a hydrothermal medium are reviewed in this work: hydrolysis, fractionation, gasification and reaction. In the last years, a significant progress was achieved in obtaining of added value products from biomass by hydrothermal technologies. However, some challenges must still be overcome before a sustainable and efficient decentralized production is achieved.