화학공학소재연구정보센터
Catalysis Today, Vol.256, 302-314, 2015
Kinetic model of homogeneous lignocellulosic biomass solvolysis in glycerol and imidazolium-based ionic liquids with subsequent heterogeneous hydrodeoxygenation over NiMo/Al2O3 catalyst
Solvolysis of wood, cellulose, hemicellulose and lignin in glycerol was investigated in the presence of homogeneous imidazolium-based ionic liquid (IL) catalysts, where the influence of the IL type, reaction time, temperature and mass transfer limitations on decomposition rate was investigated. The selection of anions (acetate, hydrogen sulphate or chloride/metal halide complex to form a Lewis acid) and cations (butyl-, methyl- or allyl-functionalised imidazolium) importantly influenced conversion, which was as high as 64.4 and 91.5 wt% for the beech wood liquefaction at 150 and 200 degrees C within 60 min. By following the mass of solid particles and their specific surface area (BET method) as a function of time and temperature, a novel kinetic model for the solvolysis of biomass and its components was developed, where reactive surface area is a key parameter that dictates the rate of solid-liquid reaction; kinetic model also considered different depolymerisation reactivity of main three wood components. Liquefied biomass was consequently hydrodeoxygenated at 225-275 degrees C in the presence of commercially available sulphide-form NiMo/gamma-Al2O3 catalyst. Rates and selectivity of hydrogenolysis, decarbonylation, decarboxylation, hydrogenation and ( hydro)cracking were followed and modelled by using previously developed lumped kinetic model, based on the Fourier transformed infrared spectroscopy (FTIR) analysis. The oxygen content of the oil phase of was less than 1.7 wt%. (C) 2015 Elsevier B.V. All rights reserved.