木质素基水热碳负载钌催化乙酰丙酸加氢反应

Hydrogenation of Levulinic Acid Catalyzed by Lignin BasedHydrothermal Carbon Supported Ruthenium

采用木质素磺酸钠为原料制备水热碳负载钌(Ru/LHC-xA)催化乙酰丙酸加氢反应制备γ-戊内酯,使用拉曼、SEM、XPS等手段对催化剂进行了表征。探讨了木质素磺酸钠基水热碳制备时的水-酸比、反应中催化剂的用量及反应温度、压力和水用量对乙酰丙酸加氢反应的影响,并对催化剂循环使用性进行了考察。在以水-酸比0.2制备的水热碳为载体,浸渍负载得到的20 mg Ru/LHC-0.2A(钌质量分数5%)催化剂作用下,10 mmol乙酰丙酸于5 mL水中,1.5 MPa初始氢气压力,80℃反应2 h,可获得99.3%的乙酰丙酸转化率和98.9%的γ-戊内酯选择性。回收后循环使用的催化剂在使用5次后选择性保持稳定,转化率有所下降,但仍高于90%。

The hydrothermal carbon-supported ruthenium(Ru/LHC-xA)was prepared by using sodium lignosulfonate as raw material to catalyze the hydrogenation of levulinic acid to prepareγ-valerolactone.The catalyst was characterized by Raman,SEM,and XPS.The water-acid ratio in the preparation of sodium lignosulfonate-based hydrothermal carbon,the amount of catalyst in the reaction,the reaction temperature,pressure and water amount on the hydrogenation of levulinic acid were discussed,and the recyclability of the catalyst was investigated.Under the action of 20 mg Ru/LHC-0.2A(ruthenium content of 5%)catalyst obtained by impregnation of the hydrothermal carbon prepared by activation with a wateracid ratio of 0.2 as a support,10 mmol levulinic acid in 5 mL water,1.5 MPa initial hydrogen pressure at 80℃for 2 h,99.3%conversion rate of levulinic acid and 98.9%selectivity ofγ-valerolactone can be obtained.The selectivity of the recycled catalyst remained stable after 5 times of use,and the conversion rate decreased,but was still higher than 90%.