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Abstract: The transesterification of dimethyl carbonate (DMC) with glycerol to produce glycerol carbonate was investigated in the presence of CaO under various reaction conditions. CaO was completely dissolved in the reaction mixture of glycerol and DMC in 5min at 75°C and at the molar ratio of glycerol/DMC/CaO of 1/2/0.01. The isolation and the characterization of the dissolved Ca species by means of TOF-SIMS, elemental analysis, and FT-IR revealed that an active species, Ca(C3H7O3)(OCO2CH3) is generated from the interaction of CaO with glycerol and DMC. The mechanistic pathways to the formations of Ca(C3H7O3)(OCO2CH3) and glycerol carbonate are discussed on the basis of experimental and spectroscopic results. [Copyright &y& Elsevier]

Abstract: Decarboxylation of glycerol carbonate (GLC) to produce 2,3-epoxy-1-propanol (glycidol) was conducted using various kinds of ionic liquids (ILs) as catalysts. ILs bearing an anion with medium hydrogen-bond basicity such as and I− exhibited the higher glycidol yields than those having an anion with low or strong hydrogen-bond. FT-IR spectroscopic analysis shows that both GLC and glycidol interact with anions of ILs through their hydroxyl groups. It was possible to improve the yield of glycidol when a zinc salt with a medium Lewis acidity was co-present along with an IL. The yield of glycidol was greatly increased up to 98% when the decarboxylation was conducted in the presence of a high-boiling aprotic solvent. Computational calculations on the mechanism using 1-butyl-3-methylimidazolium nitrate as a catalyst revealed that the first step is the -assisted ring-opening of GLC followed by the ring closure, resulting in the formation of a 3-membered ring intermediate species. [Copyright &y& Elsevier]

Abstract: An iso-octane fuel processor system with three different reaction stages, autothermal reforming (ATR) reaction of iso-octane, high temperature shift (HTS) and low temperature shift (LTS) reactions, was developed for applications in a fuel cell system. Catalytic properties of the prepared Ni/Fe/MgO/Al2O3 and Pt–Ni/CeO2 or molybdenum carbide catalysts were compared to those of commercial NiO/CaO/Al2O3 and Cu/Zn/Al2O3 catalysts for ATR and LTS reaction, respectively. It was found that the prepared catalysts formulations in the fuel processor system were more active than those of the commercial catalysts. As the exit gas of iso-octane ATR over the Ni/Fe/MgO/Al2O3 catalyst was passed through Fe3O4–Cr2O3 catalyst for HTS and Mo2C or Pt–Ni/CeO2 catalyst for LTS reaction, the concentration of CO in hydrogen-rich stream was reduced to less than 2400ppm. The results suggest that the iso-octane fuel processor system with prepared catalysts can be applied to PEMFC system when a preferential partial oxidation reaction is added to KIST iso-octane reformer system. [Copyright &y& Elsevier]