Fe、Co、Cu改性HZSM-5催化热解制备生物油试验

摘要

The Fe,Co and Cu modified HZSM-5 zeolites were prepared via impregnation method and the modified catalysts were characterized by XRD,Py-IR and BET methods.Then online catalytic upgrading of rape straw pyrolysis vapors was performed over the modified catalysts to investigate their catalytic upgrading performance and anti coking performance.The results showed that loadings of Fe,Co and Cu were well-distributed,the acid distributions on the HZSM-5 were influenced differently by Fe,Co and Cu,and the channels were modified with the decrease of pore volume.The bio-oil yields were decreased with the increase of physicochemical properties after upgrading by employing the modified HZSM-5.The yield,oxygen content,pH value,dynamic viscosity and high heating value (HHV) of bio-oil obtained by using Fe,Co and Cu/HZSM-5 were 18.37％ ～ 19.03％,15.13％ ～ 17.23％,5.05 ～ 5.12,5.16 ～ 5.22 mm2/s and 34.56 ～ 36.01 MJ/kg,respectively.The refined bio-oil was composed of a variety of organic compounds which was indicated by many kinds of chemical functional groups,the content of hydrocarbons in refined bio-oil was increased significantly.Aromatization performances of Fe/HZSM-5,Co/HZSM-5 and Zn/HZSM-5 were improved and contents of the polycyclic aromatic hydrocarbons (PAHs) were obviously increased.And after catalytic upgrading by Fe/HZSM-5 and Co/HZSM-5,the contents of the monocyclic aromatic hydrocarbons (MAHs) were relatively high.Resistance performances of Fe/HZSM-5 and Co/HZSM-5 for amorphous coke were relatively strong,while that of Co/HZSM-5 for graphite coke was enhanced obviously.%采用浸渍法对HZSM-5分别进行了Fe、Co、Cu改性;通过XRD、Py-IR和BET法对改性HZSM-5进行了表征;在两段式固定床反应器上进行了生物质热解气的在线提质试验;分析了改性HZSM-5的催化提质和抗结焦性能.结果表明,Fe、Co、Cu改性负载物分布较为均匀,没有团聚成大颗粒晶体,对HZSM-5的酸性分布产生了不同的影响,同时修饰了分子筛孔道,减小了分子筛孔容;经Fe、Co、Cu改性HZSM-5催化所得精制生物油的产率为18.37％ ～ 19.03％,O质量分数为15.13％～17.23％,pH值为5.05 ～5.12,运动黏度为5.16～5.22 mm2/s,高位热值为34.56 ～ 36.01 MJ/kg;精制生物油中含有多种官能团,有机物种类较多,烃类物质总含量有明显升高,尤其是PAHs的含量显著升高,芳构化性能显著增强,其中,经Fe/HZSM-5和Co/HZSM-5催化提质,生物油中MAHs含量相对较高;Fe/HZSM-5和Cu/HZSM-5抗无定型焦炭的性能较强,Co/HZSM-5抗石墨型焦炭的能力大幅增强.