A [(C(18)H(37))(2)N(+)(CH(3))(2)](3)[PW(12)O(40)] catalyst, assembled in an emulsion in diesel, can selectively oxidize the sulfur-containing molecules present in diesel into their corresponding sulfones by using H(2)O(2) as the oxidant under mild conditions. The sulfones can be readily separated from the diesel using an extractant, and the sulfur level of the desulfurized diesel can be lowered from about 500 ppm to 0.1 ppm without changing the properties of the diesel. The catalyst demonstrates high performance (>/=96 % efficiency of H(2)O(2), is easily recycled, and approximately 100 % selectivity to sulfones). Metastable emulsion droplets (water in oil) act like a homogeneous catalyst and are formed when the catalyst (as the surfactant) and H(2)O(2) (30 %) are mixed in the diesel. However, the catalyst can be separated from the diesel after demulsification.

By thermal treatment in vacuum, graphite oxide prepared from Hummers' method was exfoliated and partially reduced. This procedure imparts the graphene oxide (GO) the high reactivity with 2,2,6,6-tetramethyl-piperidin-1-oxyl (TEMPO) as co-catalyst for selective oxidation of 5-hydroxymethylfrufural (HMF) to 2, 5-diformylfuran (DFF) under certain conditions (100% HMF conversion with HMF selectivity 99.6% at 80 wt.% GO loading, 1 atm air pressure). This study found that GO could function as an oxidant for anaerobic oxidation of HMF during which carboxyl groups in GO were reduced. Importantly, the partially reduced GO material could continue activate molecular oxygen during aerobic oxidation. Further study showed that oxygen functionalities in GO material had a crucial effect on the catalytic oxidation of HMF.By control experiments and molecular analogues tests, a plausible mechanism was proposed in which the high reactivity was attributed to the synergistic effect of the carboxylic acid groups and unpaired electrons at GO edge defects, with TEMPO as the co-catalyst and oxygen as the terminal oxidant.

A novel hydrodeoxygenation catalytic system, Ni2P/SBA-15, has been synthesized by temperature-programmed reduction of a nickel phosphate precursor impregnated in the mesostructured silica support. The formation of this active phase was verified by X-ray diffraction, whereas the study by transmission electron microscopy revealed that the catalyst is mainly constituted of nickel phosphide particles of relatively uniform size dispersed within the SBA-15 channels. Both Ni2P/SBA-15 and a reference Ni/SBA-15 catalyst were tested for the hydrodeoxygenation of methyl oleate (C17H33–COO–CH3) in a fixed-bed continuous flow reactor. This compound was used as a convenient surrogate of triglyceride molecules present in vegetable oils that following catalytic hydrotreating yields n-alkanes as the main products. In the whole range of pressure studied (3–40 bar) and for temperatures higher than 290 °C, both systems achieve more than 80% ester conversion at 20 h–1 WHSV, although the Ni/SBA-15 catalyst presents a slightly higher activity. Overall, higher pressure and lower temperature and space velocity favors the formation of C18 hydrocarbon, which is the preferred product in terms of carbon atom economy. Nevertheless, under all the assayed conditions, the n-C18/n-C17 ratio was remarkably higher for Ni2P/SBA-15 than for Ni/SBA-15 catalysts. On the basis of these results, it can be concluded that both deoxygenation and decarboxylation occur simultaneously over the Ni2P catalyst, whereas decarboxylation and cracking are the prevailing processes over the Ni catalyst. Owing to these high yields of long-chain paraffins, Ni2P/SBA-15 can be considered as a very promising catalyst for the production of green diesel.

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An efficient strategy is developed for chemical recycling of cured epoxy resin (CEP) from its carbon fiber reinforced polymer composites (CFREP) using AlCl3/CH3COOH as the degradation system. Acetic acid swells the dense structures of CEP, facilitating the penetration of the aluminum ion catalyst into the polymer matrix. The weakly coordinating aluminum ions in CH3COOH solution selectively cleave the C–N bond while leaving the C–C, C–O (aryl alkyl ether) bonds intact. This process recovers valuable oligomers and carbon fibers from CFREP.