Phosphotungstic acid (PTA) immobilized onto imidazole functionalized fumed silica and was used as an efficient catalyst for epoxidation of a variety of olefins using aqueous H 2 O 2 as an oxidant. Negligible leaching of PTA under the reaction conditions employed indicates a strong interaction between PTA and imidazole. The immobilized catalysts could be separated and reused after the catalytic cycle. Evidence for the heterogenization of PTA on the imidazole functionalized fumed silica has been inferred from different spectroscopic techniques like IR, UV-vis, and NMR. Importantly, the nature of binding of PTA on the support has been studied in detail by solid state NMR spectroscopy using 15 N labeled imidazole support. It is clear from the NMR studies that the effective heterogenization of PTA is mainly due to imidazolium ion formation on the support by the acidic protons of PTA and the resultant ion pair.

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In early studies addressing national energy/environmental (EE) problems we concluded that co-utilization of domestic fuels can significantly reduce national reliance on imported fuels, mitigate NOx, SOx, CO2 and other undesirable emissions and provide valuable waste disposal services. Co-firing of coal and biomass for steam turbine power generation is a near-term co-utilization approach that can make use of existing facilities with relatively minor modifications. However, co-gasification by providing fuel for more efficient combustion turbines and fuel cells and co-liquification to produce transportation fuels have greater long-term EE potential. The development of optimum thermo-chemical co-conversion systems can be fostered by developing a common systematics for the pyrolysis of biomass and coal. Towards this goal we have used the large data bases from ASTM standard ultimate and proximate analyses for all fuels along natures coalification path from biomass to peat, lignite, bituminous and anthracite coal. With this composite data we find systematics in the weight percentages of carbon, hydrogen, total volatiles, fixed carbon and feedstock HHVs vs the weight percentage of oxygen. To meet the need for knowledge of the volatile constituents we have used sparsely available slow pyrolysis data in the literature and our own data to further develop a plausible semi-empirical model (SEM) that relates feedstock and product compositions. We here extend these analytic correlations to lower temperatures with the help of CCTL measurements of yields from the pyrolysis of rice hulls. We have recently applied this SEM to exam the systematic yields of a short list (SL) of products (five gases and five liquids) vs [O], the weight percentage of oxygen in the feedstock. Here anchored to the rice hull data we use our analytical relationships to estimate the yields of a long list (LL) of products including many organic compounds that are known to be slow pyrolysis products of coals and biomass. These relations are put forth as a heuristic challenge to ourselves and to specialists in biomass and coal pyrolysis to obtain more and better data and to seek improved engineering formulas that are needed to advanced co-utilization technology. Then energy debtor nations could utilize all of their available domestic fuels, including opportunity fuels, to mitigate their national EE problems. These preliminary results point to a path towards the development of a co-utilization science and technology for optimizing feedstock blends in many co-firing, co-gasifying or co-liquifying applications.

Background Major cost of bioethanol is attributed to enzymes employed in biomass hydrolysis. Biomass hydrolyzing enzymes are predominantly produced from the hyper-cellulolytic mutant filamentous fungus Trichoderma reesei RUT-C30. Several decades of research have failed to provide an industrial grade organism other than T. reesei, capable of producing higher titers of an effective synergistic biomass hydrolyzing enzyme cocktail. Penicillium janthinellum NCIM1366 was reported as a cellulase hyper producer and a potential alternative to T. reesei, but a comparison of their hydrolytic performance was seldom attempted. Results Hydrolysis of acid or alkali-pretreated rice straw using cellulase enzyme preparations from P. janthinellum and T. reesei indicated 37 and 43% higher glucose release, respectively, with P. janthinellum enzymes. A comparison of these fungi with respect to their secreted enzymes indicated that the crude enzyme preparation from P. janthinellum showed 28% higher overall cellulase activity. It also had an exceptional tenfold higher beta-glucosidase activity compared to that of T. reesei, leading to a lower cellobiose accumulation and thus alleviating the feedback inhibition. P. janthinellum secreted more number of proteins to the extracellular medium whose total concentration was 1.8-fold higher than T. reesei. Secretome analyses of the two fungi revealed higher number of CAZymes and a higher relative abundance of cellulases upon cellulose induction in the fungus. Conclusions The results revealed the ability of P. janthinellum for efficient biomass degradation through hyper cellulase production, and it outperformed the established industrial cellulase producer T. reesei in the hydrolysis experiments. A higher level of induction, larger number of secreted CAZymes and a high relative proportion of BGL to cellulases indicate the possible reasons for its performance advantage in biomass hydrolysis.

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Hemicellulolytic obligate anaerobes capable of converting a range of agricultural substrates and monomeric sugars of hemicellulose to solvents and acids were isolated from cow rumen fluid. The strains were identified as 5 strains of C. beijerinckii (3 different genotypes), 3 strains of C. acetobutylicum (2 different genotypes), 1 strain of C. butyricum and 3 strains of C. bifermentans (2 different genotypes). All of them produced cellulase-free xylanase activity. C. acetobutylicum LU1 produced solvent, a high of 5.1 gl(-1) and C.bifermentans LU1 produced xylanase activity a high of 4.2 IU ml(-1).

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