Solvent Effects on Fructose Dehydration to 5-Hydroxymethylfurfural in Biphasic Systems Saturated with Inorganic Salts
Solvent Effects on Fructose Dehydration to 5-Hydroxymethylfurfural in Biphasic Systems Saturated with Inorganic Salts
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DOI：
10.1007/s11244-008-9166-0
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发表时间：
2009-04-01
影响因子：
3.6
通讯作者：
Dumesic, James A.
中科院分区：
文献类型：
--
作者：
Roman-Leshkov, Yuriy;Dumesic, James A.
从碳水化合物的酸催化脱水获得的呋喃衍生物，如5-羟甲基糠醛（HMF），可以用作生产燃料和化学中间体的可再生化学平台。在含有有机萃取相的两相体系中，将无机盐添加到果糖的浓缩水溶液（30重量%果糖，基于无盐）中，通过增加HMF在萃取相中的分配来提高HMF产率，如通过分配系数R测量的，所述分配系数R等于有机相中HMF的浓度，所述有机相中HMF的浓度由水相中的浓度归一化。我们已经研究了溶剂选择对HMF产率的影响，在用NaCl饱和的两相系统中使用C-3-C-6范围内的伯醇和仲醇、酮和环醚作为萃取溶剂。含有C-4溶剂的两相系统在每种溶剂类别内产生最高的HMF产率。四氢呋喃在423 K下表现出高HMF选择性（83%）和高萃取能力（R = 7.1）的最佳组合。NaCl的存在提供了使用在不存在盐的情况下与水完全混溶的溶剂产生两相体系的额外益处。我们还研究了在使用正丁醇作为萃取溶剂的系统中不同盐对HMF产率的影响。Na+和K+显示了所测试的一价和二价氯化物盐的提取能力和HMF选择性的最佳组合。将盐的阴离子从Cl-改变为Br-导致类似于非盐系统的R-值和HMF选择性值，而改变为SO 4（2-）二价物质产生高R-值（8.1），但低HMF选择性值（71%）。
Furan derivatives, such as 5-hydroxymethylfurfural (HMF), obtained from acid-catalyzed dehydration of carbohydrates, can serve as renewable chemical platforms for the production of fuels and chemical intermediates. Addition of an inorganic salt to concentrated aqueous solutions of fructose (30 wt% fructose on salt free basis) in biphasic systems containing an organic extracting phase improves HMF yields by increasing the partitioning of HMF into the extracting phase, as measured by the partition coefficient, R, equal to the concentration of HMF in the organic phase normalized by the concentration in the aqueous phase. We have studied the impact of solvent choice on HMF yield using primary and secondary alcohols, ketones, and cyclic ethers in the C-3-C-6 range as extracting solvents in biphasic systems saturated with NaCl. Biphasic systems containing C-4 solvents generated the highest HMF yields within each solvent class. Tetrahydrofuran demonstrated the best combination of high HMF selectivity (83%) and high extracting power (R = 7.1) at 423 K. The presence of NaCl provided the additional benefit of creating biphasic systems using solvents that are completely miscible with water in the absence of salt. We have also studied the impact of different salts on HMF yield in systems using 1-butanol as the extracting solvent. Na+ and K+ showed the best combination of extracting power and HMF selectivity of the monovalent and divalent chloride salts tested. Changing the anion of the salt from Cl- to Br- resulted in R-values and HMF selectivity values resembling the non-salt system, while changing to the SO4 (2-) divalent species generated a high R-value (8.1), but a low HMF selectivity value (71%).