The Research Of Amorphous Catalyst For Catalytic Ethyl Lactate Synthesis Of1,2-Propylene Glycol

As our fossil raw materials are decreasing and the pressure on our environment has been building up, biomass conversion into useful energy and chemicals has been studied widely. Lactic acid, an important biomass-derived platform molecule, has been commercially produced by fermentation of renewable resources. Ethyl lactate (EL) is one of lactic acid derivative and has been commercialized recently. With advances in lactic acid fermentation, and separations and conversion technologies, retail prices of ethyl lactate less than common solvents production costs. Therefore, the production of1,2-PDO from lactate by catalytic hydrogenation is thought to be the most economic route in terms of using renewable resources.1,2-PDO is a bulk commodity chemical that is mainly used for the production of unsaturated polyester resins. It is also used as de-icing fluids, antifreeze, for the production of unsaturated polyester resins, and in the production of drugs, cosmetics, and foods. Currently, the industrial production of1,2-PDO is mainly by the hydration of propylene oxide derived from petrochemical resource, while toxic hypochlorous acid and relative high-cost H2O2are usually used in the production of propylene oxide. By the context of green and sustainable chemistry (GSC), hydrogenation of biomass derived lactic acid or ethyl lactate to1,2-propanediol shows a promising process.In this paper, a series of Co-B catalysts were prepared by changing the precursor concentration of the cobalt acetate solution. Studied the catalytic character of Co-B amorphous alloy catalyst for ethyl lactate hydrogenation to1,2-PDO. The catalyst was indicated to be characteristic of amorphous materials and dispersion uniform particle size by means of XPS, TEM and SAED.The results showed that, the best working concentration of cobalt acetate were0.75mol/L. The mole ratio of cobalt acetate and sodium borohydride was1:3.0.2mol/L sodium hydroxide was the best solvents of sodium borohydride. The optimal stir speed was100rpm with sheltering gas. The resulting Co-B catalysts were identified to be dispersion ultrafine particle amorphous alloys. Studied the catalytic character of Co-B amorphous alloy catalyst for ethyl lactate hydrogenation to1,2-propanediol. The results show that the conversion of ethyl lactate was up to98.53%, the yield of1,2-propanediol was98.32%at mild reaction conditions160℃, H2pressure6MPa for9h.