Flash Hydropyrolysis and Methanolysis of Biomass with Hydrogen and Methane.

摘要

The process chemistry of the flash pyrolysis of biomass (wood) with the reactive gases, H sub 2 and CH sub 4 and with the non-reactive gases He and N sub 2 is being determined in a 1 in. downflow tubular reactor at pressures from 20 to 1000 psi and temperatures from 600 to 1000 exp 0 C. With hydrogen, flash hydropyrolysis leads to high yields of methane and CO which can be used for SNG and methanol fuel production. With methane, flash methanolysis leads to high yields of ethylene, benzene and CO which can be used for the production of valuable chemical feedstocks and methanol transportation fuel. At reactor conditions of 50 psi and 1000 exp 0 C and approximately 1 sec residence time, the yields based on pine wood carbon conversion are up to 30% for ethylene, 25% for benzene, and 45% for CO, indicating that over 90% of the carbon in pine is converted to valuable products. Pine wood produces higher yields of hydrocarbon products than Douglas fir wood; the yield of ethylene is 2.3 times higher with methane than with helium or nitrogen, and for pine, the ratio is 7.5 times higher. The mechanism appears to be a free radical reaction between CH sub 4 and the pyrolyzed wood. There appears to be no net production or consumption of methane. A preliminary process design and analysis indicates an economically competitive system for the production of ethylene, benzene and methanol based on the methanolysis of wood. 8 refs., 18 figs., 1 tab. (ERA citation 10:030063)