Heterogeneous Catalysis of C–O Bond Cleavage for Cellulose Deconstruction: A Potential Pathway for Ethanol Production

Due to difficulty deconstructing the linkages between lignin, hemicellulose and cellulose during the conversion of cellulose to sugar, the commercial production of cellulosic ethanol is limited. This can be overcome by using a high surface-area metal catalyst. In this study, high surface-area metal NPs were synthesized using 20 mM of chloroplatinic acid and cobalt chloride prepared in THF with 0.1 mM of generation four poly(amido)amine (PAMAM) terminated dendrimer (G4-NH2) prepared in methanol and stirred for 2 hours under nitrogen. Subsequently, Pt+2 and Co+2 ions were reduced to metal zero via introduction of sodium borohydride and centrifuged for complete separation. The resulting product was heated for 2.5 hours at ~200°C. After cooling, 2.0 grams of crushed peanut shells was added to 40？mL of distilled tert-butyl methyl ether along with the separated metal nanocatalyst and refluxed on condenser at 20% for 24 hours. UV-Vis and XRD analyses show the formation of Pt and Co nanoparticles using dendrimer templating methodology. Both TLC and HPLC show that, upon introduction of the metal catalyst into the suspension of “cellulose” in TBME, separation of the cellulose into small molecules is evident. That is, release of sugar molecules via C–O bond cleavage is facilitated by the formed nanocatalysts. 1. Introduction The anticipated decline in oil production, increased demand on energy usage, and depletion of worldwide petroleum oil reserves have renewed interests in developing alternative energy sources, in particular biofuels. Currently in the United States, 97% of nonrenewable petroleum is used as a source of fuel for vehicles and other gas burning systems [1]. According to the 2012 Consumer Energy Report, the USA imports about 58% of its petroleum, crude and refined, from the western hemisphere, and consumed 20.7 million barrels of petroleum products in 2007 [2]. One logical solution to this growing energy pandemonium is the development of a sustainable energy alternative, biofuels, that eliminates the United States (and other countries) from the dependency on foreign petroleum imports and the negative impact of anthropogenic CO2 on the environment. In essence, biofuels use less fossil fuel and, thus, eliminate the fuels formed by natural resources such as anaerobic decomposition of buried dead organisms: coal, petroleum, and natural gases with high percentages of carbon. Since the 1970s, there have been many types of biomass explored, ranging from agricultural wastes (straw, olive pits, sweet potato roots, and nut shells) to energy crops (Miscanthus