Gasification is a technology that combines thermal energy with chemical energy of carbon resources to produce chemical energy as a form of syngas. The major scientific challenge is how to minimize the loss of chemical energy in the gasification, which requires decrease in the temperature of gasification as low as possible. We have developed the low temperature gasification system based on some important concepts; “separation of pyrolysis from gasification and reforming”, “intensification and elimination of volatiles-char interaction(VCI)”, “chemical recuperation of thermal energy”, “potassium catalyst migrating between gas phase and char surface”. The system enables complete gasification of biomass and lignite at temperatures as low as 700-800℃ with nearly complete removal of tar．

Chemical products nowadays are mostly produced from fossil fuels. Depletion fossil fuels in future necessitates a development of chemical industry using only an alternative feedstock, biomass. We study thermochemical methods such as pyrolysis and hydrothermal conversion for converting biomass to valuable chemicals in an environmentally friendly manner. An example is pyrolysis-based conversion of cellulose. Pyrolysis is unique amongst cellulose depolymerization methods since it does not need any solvent and other chemical reagents, and the reaction rate is very high compared to enzymatic saccharification methods. We have succeeded in reforming the pyrolysis volatiles to levoglucosenone in high yields, which is further converted to bulk and fine chemicals. In a study on lignin, we have found that oxidative pretreatment with hydrogen peroxide is very effective for depolymerization of lignin to yield its monomers with hydrogenolysis over nickel catalyst.

Japan has stated reduction of CO₂ emission to a level 80% below the current amount in 2050. Toward this difficult goal, and as a method for realizing sustainable carbon cycle society, we have proposed a process that co-produces power and chemicals from carbon resources (fossil fuels and biomass) while having carbon neutral or negative nature. Researches on the evaluation of process performance in terms of impact on CO₂ mitigation, process simulation, and development of elemental technologies are in progress.