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Recent developments in catalytic reduction with H2 of glycerol, which is a by-product of biodiesel manufacture, and the involved chemistry are summarized and reviewed. There are more than ten potential C3 products of glycerol reduction. Among them, 1,2-propanediol can be obtained in very high yield and the production from glycerol is now commercialized. Production of 1,3-propanediol, allyl alcohol and propylene are now possible in > 60%, > 90% and > 80% yield, respectively. Key reaction steps are metal-catalyzed dehydrogenation/hydrogenation, acid-catalyzed dehydration, carbonyl-induced dehydration, metal-catalyzed direct hydrogenolysis and deoxydehydration. The 2-Propanol and small-ring compounds (oxetane, propylene oxide) cannot be produced from glycerol by combinations of these key reaction steps, and no catalytic system is known at present, although the conversion reactions have minus ∆G°. [ABSTRACT FROM AUTHOR]

New materials based on electric arc furnace (EAF) dust have been produced via temperature-programmed reduction using hydrogen gas at different temperatures. Scanning electron microscopy, thermal analysis, X-ray diffraction, and Mössbauer spectroscopy suggested that the EAF dust is reduced by hydrogen at 600 and 700 °C producing reduced iron, e.g., iron (II) and iron metallic, magnetics and more active catalytic phases. The new materials show magnetic behavior as well as EAF starting material. Electron paramagnetic resonance studies using N-t-butyl-α-phenylnitrone as a trapped radical agent were performed showing characteristic signals related to paramagnetic species produced exclusively by the interaction of catalysts with hydrogen peroxide (H2O2). The new magnetic materials were successfully used for pollutant removal by adsorption followed by oxidation of model dyes such as methylene blue and indigo carmine. In addition, the great advantage of these materials is that they may be easily recovered magnetically and reused. [ABSTRACT FROM AUTHOR]

Vanadium-containing H6+xP2Mo18-xVxO62 (x = 0–3) Wells–Dawson heteropolyacid (HPA) catalysts were prepared. The successful formation of the Wells–Dawson HPAs was confirmed by FT-IR and ICP–AES analyses. The reduction potential of the H6+xP2Mo18–xVxO62 (x = 0–3) catalysts was determined by temperature-programmed reduction measurements. The Wells–Dawson HPA catalysts were applied to the vapor-phase oxidation of methacrolein and benzyl alcohol. The reduction potential, conversion of methacrolein, and conversion of benzyl alcohol showed volcano-shaped curves with respect to vanadium substitution, and decreased in the order of H8P2Mo16V2O62 > H7P2Mo17V1O62 > H9P2Mo15V3O62 > H6P2Mo18O62. A correlation between reduction potential and catalytic activity clearly showed that the conversion was monotonically increased with increasing reduction potential of the HPA catalyst in both oxidation reactions. [ABSTRACT FROM AUTHOR]