• Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Selective hydrogenation over pre-reduced 8% Cu/SiO2 catalysts has been carried out on a series of non-food oils methylesters. The catalyst shows a very high diene:monoene selectivity, thus allowing one to reduce not only the linolenic component, but also the linoleic one in this way enriching the oil in oleic acid and avoiding a contemporary increase in stearic acid concentration. This treatment improves the oxidation stability of the oil while keeping acceptable viscosity and cold properties and can be used to standardize a wide variety of different available feedstock.Practical applications: Vegetable oils from different sources can be used as primary, secondary (when they are residues of other processes), or tertiary (post-consumer wastes) feedstock for the chemical industry. Their composition can be very different as far as unsaturated components are concerned. This variability is an issue because it can lead to multiple products and moreover the unsaturation level, that is the iodine value, is strongly related to oxidation unstability. The process we propose here allows one to standardize the oil composition improving the oxidation stability and keeping acceptable fluidity. The very mild experimental conditions, 4–6 atm of H2 and 160–180°C, the use of a non-toxic and cheap metal, make this process sustainable and easily viable, e.g., in hardening plants.
    European Journal of Lipid Science and Technology 01/2012; · 2.27 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Soybean oil was partially hydrogenated using Pt supported in microporous zeolite ZSM-5 and on mesoporous alumina at various IV. Their fatty acid and triacylglycerol composition were determined with GC and HPLC, respectively, and their physical characteristics were monitored by the slip melting point, solid fat content, melting and crystallization thermograms, polymorphism behavior, and the crystal and solid fat network formation. Both the chemical and physical properties were compared with commercial fat samples. Usage of Pt instead of Ni results in a significant reduction in trans fatty acids in the hardened fat. Moreover, the catalyst support of Pt, viz. zeolite ZSM-5 versus γ-alumina, markedly affects the TAG composition. Pt/alumina fats contain large amounts of SSS and polyunsaturates (PUFA), making them unsuitable for shortening application. Because of the (regio)selective hydrogenation property of Pt/ZSM-5, sn-2 unsaturates are hydrogenated faster, yielding an enrichment of intermediately reduced TAG. In addition, this unique fat composition shows a high nutritional added-value (high content of oleate, very low content of trans fatty acids, and low content of cholesterol-raising palmitate and myristate) and high thermal stability (very low in linolenate). Moreover, their melting characteristics perfectly match those of commercial shortenings. Pt/zeolite hardened soybean oil contains spherulitic crystals with orthorhombic β′ molecular packing, arranged in an open, flexible solid network, in accordance with their high plasticity.
    Journal of Oil & Fat Industries 01/2011; · 1.59 Impact Factor

Full-text (2 Sources)

Available from
Jun 4, 2014