由于能源需求的增加,环境问题和化石燃料的枯竭,以植物油作为原料制备的生物燃油将在未来的运输燃料中扮演重要角色.以C_(18)脂肪酸(OAs)为植物油的模型化合物,在固定床反应器中研究了传统加氢裂化催化剂Ni W/SiO_2-Al_2O_3催化OAs加氢脱氧制备生物燃油的过程,考察了OAs的浓度和不同链长溶剂对OAs加氢脱氧(HDO)、脱羰/脱羧(DCO/DCO_2)以及α/β-C的断裂和异构等反应历程的影响.OAs的浓度对其转化率和产物收率,尤其是十八烷(C_(18))的收率有很大影响.C_(18)的收率随脂肪酸浓度的升高而降低,在转化充分的情况下,十七烷(C_(17))的收率随浓度的升高而增大.链长越短的溶剂越有利于提高OAs的转化率和产物收率.
C_(18)fatty acids( OAs) was taken as the model of plant-derived oils. Hydrotreating of OAs for biofuel production was investigated in a fixed bed reactor. For all experiments the same commercial Ni-W supported on modified SiO_2-Al_2O_3 by NTY zeolite catalyst was used. The effects of different OAs concentrations and different solvents on the oxygen removal reactions pathways of hydrodeoxygenation( HDO),decarbonylation / decarboxylation( DCO / DCO_2) as well as α/β-C scission and isomerizaiton reactions to form the C_(15)~ C_(18) hydrocarbons were systemically evaluated. The concentration of OAs in dodecane has a significant effect on the conversion of OAs and octadecane( C_(18)) yield( HDO reaction),which decreases with the concentration of OAs. But the heptadecane( C_(17)) yield( DCO/DCO_2reactions) increases with the concentration of OAs. Shorter chain solvent has positive effect on the conversion and product yields.