Phosphorus and nickel modified HZSM-5 zeolites(Si/Al=27)were prepared using wetness impregnation method,which were applied to catalytic fast pyrolysis of bamboo pretreated by microwave. The analysis of the catalytic performance was conducted by Py-GC/MS and the physicochemical properties were characterized by NH3-TPD,N2adsorption/desorption and XRD. The influence of the parameters including microwave pretreatment temperature,the content of phosphorus and nickel supported on catalysts was investigated. The results showed that microwave pretreatment was contributed to pyrolytic reaction and improved the distribution of pyrolysis products. Simultaneously,the phosphorus could optimize the anti-coking performance and the selectivity of mononuclear aromatics increased. The aromatization performance of nickel modified 2.5%P-HZSM-5 varied and the relative content of aromatic hydrocarbon increased and then decreased. The relative content of mononuclear aromatics also showed the same tendency and the ketones kept decreasing. The optimum product distribution(i.e.,the maximum aromatic hydrocarbon of 32.38%,the maximum mononuclear aromatics selectivity of 82.13%,the minimum yield acids of 4.61% and ketones of 9.17%)was obtained when microwave pretreatment temperature was 130℃,and the content of supported phosphorus and nickel was 2.5% and 2%,respectively.%首先采用微波对生物质竹木进行了预处理,然后浸渍法制备了P/Ni-HZSM-5二元复合催化剂,在Py-GC/MS上探究其催化微波预处理竹木快速热解性能.采用N2吸附-脱附、NH3-TPD、XRD等表征手段分析P、Ni元素改性对于催化剂的酸性、孔道分布和晶体结构等的影响,同时探究了微波预处理温度、P和Ni两种元素负载量等因素对于热解反应及产物分布的作用.结果表明:微波预处理竹木有助于提高竹木热解转化效率,并优化产物组分分布;适量 P 元素负载能够显著提高催化剂的抗结焦性能以及热解产物芳香烃中单环芳烃的选择性;负载Ni元素能够提高催化剂的芳构化能力从而获得更多的芳香烃产率以及对单环芳烃的选择性,同时降低酮类物质含量.当微波预处理温度为130℃,P负载量为2.5%,Ni负载量为2%时,获得较高芳香烃产率(32.38%)、最高单环芳烃选择性(82.13%)、最低酸含量(4.61%)和最低酮类物质含量(9.17%),而此时催化剂结焦量由未改性的6.21%降至3.77%.
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