关键词: 沙柳, 乙酰丙酸, 阴离子交换树脂, 正交实验, 分离提纯

Abstract: Preparation of levulinic acid from hydrolysis of Salix psammophila catalyzed by sulfuric acid as catalyst was studied in this paper. The effects of catalyst concentration，reaction time，reaction temperature，liquid-solid ratio on the yield of levulinic acid were investigated. By orthogonal tests，the optimum hydrolysis reaction conditions were as follows：reaction temperature 200℃，reaction time 90 min，catalyst concentration 9%，liquid-solid ratio(mL∶g) 15∶1，the highest yield of levulinic acid was 18.80%，the order of the factors was obtained according to the degree to which they could affect hydrolysis reaction as follows：reaction time > catalytic concentration > reaction temperature > liquid-solid ratio. 335 weak basic anion-exchange resin was used for separation and purification of hydrolysis mixed solution，under the static conditions of adsorption temperature 35 ℃，amount of resin 15 g，eluent concentration (HCl) 0.5 mol/L，recovery of levulinic acid was 95.35%.

Key words: Salix psammophila, levulinic acid, anion-exchange resin, orthogonal tests, separation and purification