硝酸钾负载介孔炭催化光皮树油酯交换反应研究

KNO_(3)-Loaded Mesoporous Carbon Catalyzed Transesterification Reaction of Cornus wilsoniana Oil

以蔗糖为原料,SBA-15为模板剂,采用硬模板法制备介孔炭CMK-3,CMK-3负载KNO_(3)制得介孔炭基固体碱催化剂KNO_(3)/CMK-3,并将KNO_(3)/CMK-3用于催化光皮树油酯交换反应制备生物柴油。以生物柴油酯交换率为评价指标,通过单因素试验对固体碱催化剂KNO_(3)/CMK-3最佳制备条件进行探索,结果表明:在焙烧温度450℃、焙烧时间2 h、KNO_(3)负载量7.5%,制得的7.5%KNO_(3)/CMK-3催化性能最佳,催化光皮树油(20 g)合成生物柴油酯交换率可达95.95%。使用SEM、TEM、BET、XRD、CO_(2)-TPD等检测手段对催化剂进行表征,7.5%KNO_(3)/CMK-3的碱量0.9211 mmol/g,比表面积93.95 m^(2)/g,总孔容0.1146 cm^(3)/g,孔径4.879 nm,改性前后,介孔炭碱性活性分子负载其上,炭骨架棒状结构保持良好。FT-IR、GC-MS等分析表明:制得的生物柴油产品中亚油酸甲酯和油酸甲酯质量分数最高,分别为45.97%和32.08%。

Using sucrose as the carbon source and SBA-15 as the mesoporous template,the CMK-3 mesoporous carbon was prepared by the hard template method.And then,the mesoporous carbon-based solid base catalyst by loading KNO_(3)that could efficiently catalyze the production of biodiesel from Cornus wilsoniana oil was prepared by the impregnation method.Catalytic experiments were carried out to determine the catalytic activity of KNO_(3)/CMK-3 and explore the best preparation conditions by comparing the transesterification rate of biodiesel.The catalyst was characterized by SEM,TEM,BET,XRD,CO_(2)-TPD,etc..The research results showed that the optimal loading conditions were calcination temperature 450℃,calcination time 2 h,loading amount of KNO_(3)7.5%.Under these conditions,the transesterification rate of biodiesel from C.wilsoniana oil could reach 95.95%.The catalyst 7.5%KNO_(3)/CMK-3 was characterized by SEM,TEM,BET,XRD,CO_(2)-TPD and so on,the results showed that the alkali content of the catalyst 7.5%KNO_(3)/CMK-3 was 0.9211 mmol/g,the surface area was 93.95 m^(2)/g,the total pore volume was 0.1146 cm^(3)/g and the pore size was 4.879 nm.Before and after the modification,the alkaline active molecule was loaded on the meso-carbon and the rodstructure of carbon skeleton remained stable.The FT-IR and GC-MS analysis results showed that the mass fractions of methyl linolenate and methyl oleate in the obtained biodiesel were the highest,and were 45.97%and 32.08%.