(730b) Ru/CNT Catalyst for Supercritical Water Gasification of Biomass
AIChE Annual Meeting
2024
2024 AIChE Annual Meeting
Sustainable Engineering Forum
Reactor Engineering for Biomass Feedstocks I
Thursday, October 31, 2024 - 4:00pm to 4:25pm
Supercritical water gasification is a promising technology to gasify wet biomass for energy recovery. It has been studied by many researchers and its commercialization is sought. However, due to the high price for the process, it is not easy to commercialize this process. This high price is due to the fact that for complete gasification, high temperature or effective catalyst is needed. When high temperature is employed, the reactor has to endure high pressure under high reaction temperature, and the cost of the reactor is high. When effective catalyst such as ruthenium is employed, the cost of catalyst is very high. To circumvent this problem, our group developed Ru/CNT catalyst, where ruthenium is impregnated onto carbon nanotube. First, stability of carbon nanotube in supercritical water was studied. Carbon nanotube reacted with supercritical water, but its rate was more than one order of magnitude lower than that of activated carbon, which was employed as catalyst for supercritical water gasification by Antalâs group, University of Hawaii. Then, ruthenium was impregnated onto the carbon nanotube, and the catalyst was packed into the reactor. When glucose solution was fed, complete gasification was achieved with small amount of catalyst. The flow rate of the feedstock as well as catalyst amount in the packed bed was changed, and carbon gasification efficiency was determined experimentally. The result was well expressed with the first order reaction model for both homogeneous and heterogeneous reactions. The amount of ruthenium needed is more than one order of magnitude lower than previous study, showing the high possibility of achieving low-cost commercial supercritical water gasification process.