CARBON-CATALYZED GASIFICATION OF ORGANIC FEEDSTOCKS IN SUPERCRITICAL WATER

Spruce wood charcoal, macadamia shell charcoal, coal activated carbon, and coconut shell activated carbon catalyze the gasification of organ ic compounds in supercritical water. Feedstocks studied in this paper include glycerol, glucose, cellobiose, whole biomass feedstocks (depit hed bagasse liquid extract and sewage sludge), and representative Depa rtment of Defense (DoD) wastes (methanol, methyl ethyl ketone, ethylen e glycol, acetic acid, and phenol). The effects of temperature, pressu re, reactant concentration, weight hourly space velocity, and the type of catalyst on the gasification of glucose are reported. Complete con version of glucose (22% by weight in water) to a hydrogen-rich synthes is gas was realized at a weight hourly space velocity (WHSV) of 22.2 h (-1) in supercritical water at 600 degrees C, 34.5 MPa. Complete conve rsions of the whole biomass feeds were also achieved at the same tempe rature and pressure. The destruction efficiencies for the representati ve DoD wastes were also high. Deactivation of the carbon catalyst was observed after 4 h of operation without swirl in the entrance region o f the reactor, but the carbon gasification efficiency remained near 10 0% for more than 6 h when a swirl generator was employed in the entran ce of the reactor.