【摘要】 采用不同硅铝比的HZSM-5作为煤热解挥发物提质催化剂,研究了催化剂酸性特征对挥发物提质后的焦油品质、催化剂积炭的影响。结果表明,随着硅铝比的增加,HZSM-5的强酸和弱酸量均降低;硅铝比从23增大到310时,催化剂积炭量从120.1 mg/g-catalyst降到23.9 mg/g-catalyst。并且,HZSM-5中强酸与弱酸位点的比值越高,焦油中轻质组分的含量越高。随硅铝比的降低,HZSM-5酸性增强,所得焦油中芳烃组分含量逐渐提高,这表明,HZSM-5在催化煤热解过程中促进了挥发物的氢转移、环化、芳构化反应,从而生成了更多的芳烃组分。更多还原

【Abstract】 The effects of SiO₂/Al₂O₃ ratio of HZSM-5 on the tar quality and coke formation during catalytic upgrading of coal pyrolysis volatiles were investigated. The results showed that the carbon deposition amount decreased with the increase of the SiO₂/Al₂O₃ ratio of HZSM-5 due to the decrease of strong and weak acid amount. When the SiO₂/Al₂O₃ ratio increased from 23 to 310,the carbon deposition amount decreased from 120.1 mg/g-catalyst to 23.9 mg/g-catalyst. Moreover,the higher ratio of strong and weak acid amount led to lighter fraction in tar. With the decrease of SiO₂/Al₂O₃ ratio,the acid strength was enhanced so that the aromatics content in the tars decreased,indicating that the stronger acidic sites promoted the dehydrogenation,cyclization and aromatization reactions of volatiles,thus leading to higher yield of aromatics during catalytic coal pyrolysis.更多还原