固体酸SO42-/TiO2-ZrO2催化制备乙酰丙酸的研究

以蔗糖为原料,固体SO42-/TiO2-ZrO2为催化剂,以水为溶剂制备乙酰丙酸。研究了浸渍用硫酸浓度和催化剂焙烧温度对催化剂活性的影响,并探讨了不同反应条件及催化剂重复使用次数对乙酰丙酸得率的影响。用XRD和NH3-TPD对使用前后的催化剂的结构和酸性进行了表征。实验结果表明,1.0 mol/L硫酸浓度浸渍,550℃焙烧3 h的催化剂活性较强。在催化剂投加量为1.0 g,反应温度为190℃的条件下反应1 h,乙酰丙酸摩尔得率高达50.0%。回收的SO42-/TiO2-ZrO2催化剂焙烧后在多次重复使用过程中仍然表现出较好的催化活性。

Study on Synthesis of Levulinic Acid with Solid Acid SO42-/TiO2-ZrO2 as Catalyst

Levulinic acid was prepared by solid SO42-/TiO2-ZrO2 catalyst from sucrose in water.The influence of impregnation concentration of sulfuric acid and calcinations temperature on catalyst activity was studied.The effect of different reaction conditions and catalyst reuse cycle on levulinic acid yield was investigated.The surfaces structure and acidity changes of the fresh and used catalysts were characterized by XRD and NH3-TPD.Experimental results indicated that the optimal catalyst could be obtained under the following conditions: 1mol/L impregnation concentration of sulfuric acid,550 ℃ of calcination temperature and 3 h of calcinations time.And the yield of levulinic acid was about 50.0%(molar percent) under the optimum conditions: amount of catalyst 1g,reaction temperature 190℃ and reaction time 1h.The recovered SO42-/TiO2-ZrO2 catalyst after calcination was found to remain high catalytic activity after being reused for several times.