| Biomass, lignocellulose in particular, is a potentially inexhaustible feedstock to produce environmentally safe fuels. It first can be hydrolyzed to simple sugars, which are further processed by fermentation. Another route to biomass utilization is to produce volatile fatty acid salts in an anaerobic environment. The fatty acid salts can be converted to a mixture of C3-C7 ketones by prolysis. The final step is to hydrogenate the mixed ketones to their corresponding alcohols for use as fuels.;Using AFEX-treated wheat straw as substrate for hydrolysis, the HCH-1 model has been proven superior to other competitive models in a previous study. Here we show that it also accurately describes initial rate data for untreated wheat straw. By comparing the three parameters in the HCH-1 model at ;Among the initial rate models for ketone hydrogenation, Model 6, which follows the Langmuir mechanism with the assumption of surface reaction as the rate controlling step, best represents the data. Model 6 is a first-order reaction with respect to hydrogen rather than the half-order reported by other authors. In addition, data at three different temperatures indicate that Model 6 follows the Arrhenius/Van't Hoff law. For the long-term reaction data at a total pressure of 7.80 atm, a revised Model 6 with new additional parameters accurately fit the data for pure-component hydrogenation. The discrepancy between predicted and experimental conversions for mixed ketones hydrogenation indicates that further study is needed. |
