摘要:采用热重分析法考察小球藻粉的热解特性,以HZSM-5、HY分子筛为催化剂,对小球藻粉直接热解和催化热解后生物油的化学组成进行对比分析,研究2种分子筛催化剂对催化热解的影响。结果表明,小球藻粉的热解温度为160~600℃;小球藻粉加入HZSM-5分子筛催化剂催化热解后,十六酸及含氮化合物的含量大幅降低,烃类物质的含量提高,含有较多甲苯、二甲苯等芳香烃;经HY分子筛催化热解后,十六酸含量降低,含氮化合物的含量大幅提高,形成大量的萘等多环芳烃;HZSM-5分子筛具有较好的催化脱氧、择形芳构化功能,HY分子筛择形性较差,导致多环芳烃及含氮化合物的含量提高。
关键词:热解;生物油;小球藻;分子筛
Abstract:The pyrolysis characteristics of chlorella vulgaris powders were investigated by thermogravimetry technology.Using HZSM-5 zeolite and HY zeolite as catalysts,a comparison on chemical composition of bio-oil from chlorella vulgaris powders by direct and catalytic pyrolysis approaches was presented.The influence of the two kinds of catalysts on catalytic pyrolysis was explored.The results show that the pyrolysis temperature of chlorella vulgaris powders ranges from 160 to 600 ℃.The contents of hexadecanoic acid and nitrogenous compounds are greatly decreased by catalytic pyrolysis of chlorella vulgaris powders with HZSM-5 zeolite.The amount of hydrocarbons is increased,including plentiful aromatic hydrocarbons such as toluene and xylenes.The content of hexadecanoic acid is reduced by catalytic pyrolysis of chlorella vulgaris powders with HY zeolite,but the content of nitrogenous compounds is greatly increased.The bio-oil contains abundant polycyclic aromatic hydrocarbon,especially naphthalene.HZSM-5 zeolite is highly active in deoxygenation and aromatization.Due to the poor shape-selectivity of HY zeolite,the contents of polycyclic aromatic hydrocarbon and nitrogenous compounds are increased.
Keywords:pyrolysis;bio-oil;chlorella vulgaris;molecular sieve