A one-pot system used for the chemical/catalytic conversion of cellulosic biomass, and the product extraction was developed. The latter phase was carried out by a distillation technique that combines a temperatureprogrammed heating with a vacuum level-programmed evacuation (technique of mild vacuum-assisted distillation, MVAD). No environmentally harmful solvent was used: only a high boiling paraffin (n-dodecane) was used to help distil the heavy products. The obtained liquid fractions (light and heavy fractions) could be used, after drying and removal of unused alcohol, for blending into gasoline or diesel/biodiesel. Two different conversion procedures were used: ethanolysis (direct acid-catalyzed conversion in ethanol medium) and a sequential procedure, the latter consisting of the ''acid hydrolysis followed by the esterification of resulting acids with ethanol''. By using wood residues as raw material, the yields in ethyl levulinate and other by-products-with the only exception of diethyl ether (DEE), were quite similar for both procedures. The incorporation of some H-USY zeolite could significantly decrease the yield of DEE in the ethanolysis procedure. Reported results obtained with some other biomass feedstocks (particularly, switch grass) showed a good relationship between the product levulinate yield and the cellulose content of the raw material.

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The supported Ni co-catalyst surface of the thermocatalytic cracking (TCC) hybrid catalyst produces very active hydrogen species. Such species, once transferred (spilt-over) onto the surface of the main catalyst component (cracking sites), interact with the adsorbed reaction intermediates, resulting in a decreased formation of coke precursors (polynuclear aromatics) and the dearomatization/ring-opening of some heavy compounds of the feed. Simultaneously, there is a significant increase in the product yields of light olefins, particularly ethylene and propylene. Analysis of reaction products after 10 h of continuous reaction shows the very significant effects of these co-catalysts on heavy feedstocks such as vacuum gas oils, although the amounts of these (spilt-over) hydrogen species are very small, in comparison to the molecular hydrogen produced by the cracking reactions.

The thermocatalytic cracking (TCC) process, which can selectively produce light olefins (mostly, ethylene and propylene for the petrochemical industry) and transportation fuels (gasoline and diesel fuel), combines the effects of thermal and catalytic cracking reactions. The TCC catalysts consist mainly of mixed metal oxides supported on a high-surface area -thermally stabilized alumina. The best TCC catalyst formulation includes a co-catalyst, which provides the main catalyst component with active hydrogen species formed from hydrogen and other hydrocarbons, particularly methane, produced mainly by thermal cracking. The interparticular interactions of these hydrogen spilt-over species can occur because these species can be easily transferred from one particle to the other through the newly formed pore connections