酸洗改性对USY分子筛结构及煤催化热解性能的影响  

Effect of acid-leached modification on the structure of USY zeolite and catalytic pyrolysis performance of coal

作　　者：吴卓卓 杨志远[1,2] 鞠晓茜 李银艳 段欣博 周安宁 WU Zhuozhuo;YANG Zhiyuan;JU Xiaoqian;LI Yinyan;DUAN Xinbo;ZHOU Anning(College of Chemistry and Chemical Engineering,Xi′an University of Science and Technology,Xi′an 710054,China;Key Laboratory of Coal Resources Exploration and Comprehensive Utilization,Ministry of Natural Resources,Xi′an 710021,China)

机构地区：[1]西安科技大学化学与化工学院,陕西西安710054 [2]自然资源部煤炭资源勘查与综合利用重点实验室,陕西西安710021

出　　处：《洁净煤技术》2023年第5期21-27,共7页Clean Coal Technology

基　　金：国家自然科学基金资助项目(41772166);陕西省重点研发计划资助项目(2017ZDCXL-GY-10-01-02,2018GY-076);自然资源部煤炭资源勘查与综合利用重点实验室重大专项资助项目(SMDZ-2019ZD-2)。

摘　　要：煤热解获得轻质芳烃(如苯、甲苯、二甲苯等)对煤化工洁净高效生产具有重要意义。以商业USY分子筛为母体,考察酸种类、酸浓度对USY分子筛结构及煤催化热解性能的影响,通过X射线衍射仪、扫描电子显微镜、氮气吸脱附等表征手段分析改性USY分子筛的织构、形貌,研究了酸处理对USY分子筛结构的影响;利用Py-GC/MS探讨了改性USY分子筛对神府煤催化热解产物的影响。结果表明:USY分子筛的结晶度随酸浓度的增加而降低,在保证USY分子筛晶体结构良好的条件下,盐酸的最大浸渍浓度为0.4 mol/L,硫酸和磷酸浓度为0.2 mol/L。盐酸改性可提高USY分子筛的平均孔径和介孔孔容。酸洗改性USY分子筛有利于煤催化热解轻芳烃的生成,尤其是对萘系生成具有较好的选择性。HCl-USY-0.4催化效果最好,催化热解产物中苯系、甲苯、二甲苯、萘系相对含量分别为11.39%、9.36%、11.68%、31.27%。Light aromatics(such as benzene,toluene,xylene,etc.)obtained from coal pyrolysis have significance for clean and efficient production of coal chemical industry.Based on commercial USY zeolite as the parent,this work investigates the types of acid,acid concentration on the influence of USY zeolite structure and coal catalytic pyrolysis performance.The texture and morphology of the modified zeolites were characterized by X-ray diffraction,scanning electron microscopy and N 2 adsorption-desorption,and the effect of acid treatment on the pore structure of USY zeolite was studied.The catalytic cracking effect of the modified USY zeolite catalysts on the Shenfu coal was studied by Py-GC/MS.The results show that the crystallinity of USY zeolites decreases gradually with the increase of acid concentration.Under the condition of maintaining the skeleton integrity of the USY zeolites,the biggest impregnated HCl concentration is 0.4 mol/L,H 2 SO 4 and H 3 PO 4 is 0.2 mol/L.HCl modification can improve the average pore diameter and mesoporous volume of USY zeolite.The acid-leached USY zeolites are favorable for the formation of light aromatics,especially naphthalenes,in coal pyrolysis.HCl-USY-0.4 has the best catalytic effect,and the relative contents of benzenes,toluene,xylene and naphthalenes are 11.39%,9.36%,11.68%and 31.27%,respectively.

关 键 词：USY分子筛 酸洗 煤 催化热解 轻质芳烃 

分 类 号：TQ426[化学工程] TQ530.2