开展了以固体酸替代无机酸降解模型物质六元糖的研究。利用小型高压反应釜测定了在130~160℃范围内Amberlyst35W和36W树脂催化下葡萄糖和果糖的降解反应动力学,结果表明35W树脂的加入对葡萄糖异构化成果糖的速率影响较小,但可提高果糖脱水生成中间产物5-羟甲基糠醛以及5羟甲基糠醛脱羧生成乙酰丙酸的速率,从而提高产物乙酰丙酸的收率;在0.2g35W树脂催化下,葡萄糖和果糖的降解反应活化能分别为111、97.0kJ·mol^-1。Amberlyst36W与35W具有相似的催化活性,同时Amberlyst35W和36W在实验条件下可以重复使用。该研究结果证实了用耐水型强酸性树脂替代现有的无机酸催化制备乙酰丙酸的可能性。
The decomposition of model substances-hexose catalyzed by strong acidic resins instead of inorganic acids was studied. With a small high-pressure batch reactor, decomposition kinetics of glucose and fructose catalyzed by Amberlyst 35W and 36W resins were determined. The results showed that although addition of 35W resin had little influence on the isomerization from glucose to fructose, the reactions for dehydration of fructose into 5-hydroxymethylfurfural and hydrolysis of 5-hydromethylfurfural to levulinic acid were greatly sped up, resulting in higher levulinic acid yield. With 0.2 g of the 35W resin amount added, the activation energies estimated were 111 kJ · mol^-1 for glucose decomposition and 97.0 kJ · mol^-1 for fructose decomposition. Also, it was found that Amberlyst 36W showed similar catalytic behavior as 35W and both 35W and 36W can be reused without decrease of activity. The work proved the possibility of substituting inorganic acid with strong acidic resins for levulinic acid preparation from biomass.