【摘要】 采用低分子量的有机溶剂和无机盐组成的盐析萃取体系,从模拟液和木糖渣催化反应液中萃取回收乙酰丙酸。考察了乙酰丙酸在不同盐析萃取体系中的分配行为,筛选出（NH₄）₂SO₄/丙酮为最佳体系,并探讨了该体系中（NH₄）₂SO₄、丙酮的量以及pH和温度对乙酰丙酸回收性能的影响。在最优条件下,采用25 wt%（NH₄）₂SO₄-25 wt%丙酮体系,乙酰丙酸的回收率和分配系数分别为87.3%和10.4。萃取后,丙酮可通过蒸发回收循环利用;通过稀释结晶,（NH₄）₂SO₄的回收率约95.5%。将丙酮/（NH₄）₂SO₄盐析萃取体系进一步应用于木糖渣反应液,其中乙酰丙酸的回收率可达80%。更多还原

【Abstract】 In present work,a salting-out extraction system consisting of low molecular weight organic solvents and inorganic salts was developed for the recovery of levulinic acid from simulated solution and the mixture directly derived from corncob residue.The distribution behavior of levulinic acid in different salting-out extraction systems was investigated.Ammonium sulfate/acetone was selected as the best salting-out extraction system.The effects of the mass fraction of（NH₄）₂SO₄,the amount of acetone,pH and temperature of the system on the recovery process of levulinic acid were discussed.Under optimal conditions,the recovery rate and distribution coefficient of levulinic acid were 87.3% and 10.4 respectively,by using 25 wt%（NH₄）₂SO₄-25 wt%acetone salting-out extraction system.After extraction,acetone could be recycled by evaporation,and the recovery of（NH₄）₂SO₄ was about 95.5%by dilution crystallization.Furthermore,the acetone/（NH₄）₂SO₄ salting-out extraction system was used in corncob residue reaction solution and also showed excellent recovery rate（80%） for levulinic acid.更多还原