MgO改性HMCM-22分子筛催化苯与甲醇烷基化制甲苯
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摘要
采用机械湿混法制备了一系列MgO改性的HMCM-22分子筛催化剂,通过XRD、SEM、N2物理吸/脱附、Py-IR等手段对改性催化剂的晶体结构、表面形貌、孔道变化和酸性酸量等性质进行了表征,发现负载MgO能够有效地调变HMCM-22分子筛的酸性,但对其孔道的调节效果较弱。采用微反装置评价催化剂性能,在进料比为1∶1、常压、温度为400℃、反应时间4h、质量空速WHSV=10h-1的条件下,考察了不同MgO负载量下的MgO/HMCM-22催化性能,研究发现MgO负载量介于3%～6%的MgO/HMCM-22催化剂具有优越的催化性能,苯转化率>50%,甲苯选择性>60%。同时在该反应条件下,对3%MgO/HMCM-22催化剂的稳定性进行了考察,结果表明,反应40h内,苯的转化率始终保持在50%以上;反应至第80h时,苯的转化率仍然可达23%,且甲苯选择性始终保持在65%左右。
A series of HMCM-22 molecular sieve catalysts modified by MgO were prepared by mechanical wet mixing method. The crystal structure, surface morphology, pore channel change and acid content of the modified catalysts were characterized by means of XRD, SEM, N2 physical adsorption and desorption, Py-IR and so on. It was found that the addition of MgO could effectively adjust the acidity of HMCM-22 molecular sieve, but the regulation effect on the pore channel was weak. The catalyst performance was evaluated on a microreactor under the conditions of feed ratio of 1∶1, atmospheric pressure, temperature of 400℃, reaction time of 4 h, and weight hourly space velocity(WHSV=10 h-1). The catalytic performance of MgO/HMCM-22 with different MgO loading was investigated. It was found that all of MgO/HMCM-22 catalysts with MgO loading from 3% to 6% had excellent catalytic performance,the conversion of benzene was more than 50%, and the toluene selectivity was more than 60%. At the same time, the stability of 3% MgO/HMCM-22 catalyst was also investigated under the same condition.The results showed that the conversion of benzene remained above 50% within 40 h, and still up to 23%within 80 h and the selectivity of toluene remained about 65%.
A series of HMCM-22 molecular sieve catalysts modified by MgO were prepared by mechanical wet mixing method. The crystal structure, surface morphology, pore channel change and acid content of the modified catalysts were characterized by means of XRD, SEM, N2 physical adsorption and desorption, Py-IR and so on. It was found that the addition of MgO could effectively adjust the acidity of HMCM-22 molecular sieve, but the regulation effect on the pore channel was weak. The catalyst performance was evaluated on a microreactor under the conditions of feed ratio of 1∶1, atmospheric pressure, temperature of 400℃, reaction time of 4 h, and weight hourly space velocity(WHSV=10 h-1). The catalytic performance of MgO/HMCM-22 with different MgO loading was investigated. It was found that all of MgO/HMCM-22 catalysts with MgO loading from 3% to 6% had excellent catalytic performance,the conversion of benzene was more than 50%, and the toluene selectivity was more than 60%. At the same time, the stability of 3% MgO/HMCM-22 catalyst was also investigated under the same condition.The results showed that the conversion of benzene remained above 50% within 40 h, and still up to 23%within 80 h and the selectivity of toluene remained about 65%.
引文
[1]凡文.中国甲苯市场分析及前景展望[J].中国石油和化工经济分析, 2017(11):52-54.FAN Wen. China toluene market analysis and prospects[J]. China Petroleum and Chemical Economic Analysis, 2017(11):52-54.
[2]李贵贤,杜知松,季东,等. Ce/HZSM-5分子筛催化剂在苯与甲醇制甲苯反应中的催化性能[J].石油学报(石油加工), 2018, 34(2):277-283.LI Guixian, DU Zhisong, JI Dong, et al. Catalytic performance of Ce/HZSM-5 molecular sieve catalyst in the reaction of benzene with methanol toluene[J]. Acta Petrolei Sinica(Petroleum Processing Section), 2018, 34(2):277-283.
[3]田晏.浅谈甲苯特性及市场影响因素[J].中国石油和化工经济分析, 2013(6):54-57.TIAN Yan. Discussion on toluene characteristics and market influencing factors[J]. China Petroleum and Chemical Economic Analysis, 2013(6):54-57.
[4]范宗良,边杰,季东,等.改性纳米ZSM-11分子筛及其催化苯与甲醇烷基化反应的性能[J].分子催化, 2018, 32(2):180-186.FAN Zongliang, BIAN Jie, JI Dong, et al. Modified nano ZSM-11molecular sieve and its catalytic performance for alkylation of benzene with methanol[J]. Journal of Molecular Catalysis(China), 2018, 32(2):180-186.
[5]李贵贤,孙烈东,季东,等.改性beta分子筛催化苯和甲醇制甲苯反应的研究[J].分子催化, 2017, 31(1):74-81.LI Guixian, SUN Liedong, JI Dong, et al. Study on the reaction of benzene and methanol toluene catalyzed by modified beta zeolite[J].Journal of Molecular Catalysis(China), 2017, 31(1):74-81.
[6] LYU Jinghui, HU Hualei, TAIT Carolyn, et al. Benzene alkylation with methanol over phosphate modified hierarchical porous ZSM-5 with tailored acidity[J]. Chinese Journal of Chemical Engineering, 2017, 25(9):1187-1194.
[7] LI Y, WEN Z, WEI Z, et al. Study on catalytic alkylation of benzene with methanol over ZSM-22 and ZSM-35[J]. China Petroleum Processing&Petrochemical Technology, 2017(4):38-46.
[8]季东,杜知松,王东亮,等. Nd/HZSM-5分子筛催化苯与甲醇烷基化的研究[J].分子催化, 2018, 32(1):27-34.JI Dong, DU Zhisong, WANG Dongliang, et al. Studies on alkylation of benzene with methanol catalyzed by Nd/HZSM-5 molecular sieve[J].Journal of Molecular Catalysis(China), 2018, 32(1):27-34.
[9] DONG P, LI Z, JI D, et al. Catalytic benzene mono-alkylation over three catalysts:improving activity and selectivity with M-Y catalyst[J].Journal of Inclusion Phenomena&Macrocyclic Chemistry, 2018, 90(1/2):149-155.
[10] DONG P, LI Z, WANG X, et al. The alkylation reaction of benzene with methanol to produce toluene:YC and Y-CCs catalyst[J]. Green Chemistry Letters and Reviews, 2018, 11(2):158-164.
[11] WANG Q T, HAN W W, HU H L, et al. Influence of the posttreatment of HZSM-5 zeolite on catalytic performance for alkylation of benzene with methanol[J]. Chinese Journal of Chemical Engineering,2017, 25(12):1777-1783.
[12]刘司,闻振浩,杨大强,等. HF改性的Pt/ZSM-5催化剂在苯和甲醇烷基化反应中的应用[J].应用化学, 2016, 33(5):571-576.LIU Si, WEN Zhenhao, YANG Daqiang, et al. Application of HF modified Pt/ZSM-5 catalyst in alkylation of benzene and methanol[J].Applied Chemistry, 2016, 33(5):571-576.
[13]赵博.改性纳米HZSM-5催化剂上苯和甲醇的烷基化[D].大连:大连理工大学, 2013.ZHAO Bo. Alkylation of benzene and methanol on modified nanoHZSM-5 catalyst[D]. Dalian:Dalian University of Technology, 2013.
[14]刘全昌.改性ZSM-5和MCM-49分子筛上苯与甲醇烷基化研究[D].北京:北京化工大学, 2013.LIU Quanchang. Alkylation of benzene with methanol on modified ZSM-5 and MCM-49 molecular sieves[D]. Beijing:Beijing University of Chemical Technology, 2013.
[15] SMIRNIOTTIS P G, RUCKENSTEIN E. Alkylation of benzene or toluene with MeOH or C2H4over ZSM-5 or beta zeolite:effect of the zeolite pore openings and of the hydrocarbons involved on the mechanism of alkylation[J]. Industrial&Engineering Chemistry Research, 1995, 34(5):1517-1528.
[16] ZHU Z, CHEN Q, XIE Z, et al. The roles of acidity and structure of zeolite for catalyzing toluene alkylation with methanol to xylene[J].Microporous&Mesoporous Materials, 2006, 88(1):16-21.
[17] ADEBAJO M O, HOWE R F, LONG M A. Methylation of benzene with methanol over zeolite catalysts in a low pressure flow reactor[J].Catalysis Today, 2000, 63(2):471-478.
[18] HU H, LYU J, CEN J, et al. Promoting effects of MgO and Pd modification on the catalytic performance of hierarchical porous ZSM-5 for catalyzing benzene alkylation with methanol[J]. RSC Advances,2015, 5(77):63044-63049.
[19]丁春华,王祥生,郭新闻.氧化物改性MCM-22上甲苯与甲醇的烷基化性能研究[J].石油学报(石油加工), 2007(5):38-42.DING Chunhua, WANG Xiangsheng, GUO Xinwen. Alkylation performance of toluene and methanol on oxide modified MCM-22[J].Acta Petrolei Sinica(Petroleum Processing), 2007(5):38-42.
[20] XUE B, LI Y, DENG L. Selective synthesis of p-xylene by alkylation of toluene with dimethyl carbonate over MgO-modified MCM-22[J].Catalysis Communications, 2010, 10(12):1609-1614.
[21]柯明,周慧云,周耀文. MCM-22分子筛改性研究进展[J].当代化工, 2015, 44(11):2629-2632, 2634.KE Ming, ZHOU Huiyun, ZHOU Yaowen. Research progress of MCM-22 molecular sieve modification[J]. Contemporary Chemical Industry,2015, 44(11):2629-2632, 2634.
[22] TAN W, LIU M, ZHAO Y, et al. Para-selective methylation of toluene with methanol over nano-sized ZSM-5 catalysts:synergistic effects of surface modifications with SiO2, P2O5, and MgO[J]. Microporous&Mesoporous Materials, 2014, 196:18-30.
[23]薛冰,吴浩,文琳智,等.硼酸改性MCM-22分子筛催化甲苯烷基化合成对二甲苯[J].化工进展, 2017, 36(6):2177-2182.XUE Bing, WU Hao, WEN Linzhi, et al. Boric acid modified MCM-22molecular sieve catalyzed toluene alkylation to synthesize p-xylene[J].Chemical Industry and Engineering Progress, 2017, 36(6):2177-2182.
[2]李贵贤,杜知松,季东,等. Ce/HZSM-5分子筛催化剂在苯与甲醇制甲苯反应中的催化性能[J].石油学报(石油加工), 2018, 34(2):277-283.LI Guixian, DU Zhisong, JI Dong, et al. Catalytic performance of Ce/HZSM-5 molecular sieve catalyst in the reaction of benzene with methanol toluene[J]. Acta Petrolei Sinica(Petroleum Processing Section), 2018, 34(2):277-283.
[3]田晏.浅谈甲苯特性及市场影响因素[J].中国石油和化工经济分析, 2013(6):54-57.TIAN Yan. Discussion on toluene characteristics and market influencing factors[J]. China Petroleum and Chemical Economic Analysis, 2013(6):54-57.
[4]范宗良,边杰,季东,等.改性纳米ZSM-11分子筛及其催化苯与甲醇烷基化反应的性能[J].分子催化, 2018, 32(2):180-186.FAN Zongliang, BIAN Jie, JI Dong, et al. Modified nano ZSM-11molecular sieve and its catalytic performance for alkylation of benzene with methanol[J]. Journal of Molecular Catalysis(China), 2018, 32(2):180-186.
[5]李贵贤,孙烈东,季东,等.改性beta分子筛催化苯和甲醇制甲苯反应的研究[J].分子催化, 2017, 31(1):74-81.LI Guixian, SUN Liedong, JI Dong, et al. Study on the reaction of benzene and methanol toluene catalyzed by modified beta zeolite[J].Journal of Molecular Catalysis(China), 2017, 31(1):74-81.
[6] LYU Jinghui, HU Hualei, TAIT Carolyn, et al. Benzene alkylation with methanol over phosphate modified hierarchical porous ZSM-5 with tailored acidity[J]. Chinese Journal of Chemical Engineering, 2017, 25(9):1187-1194.
[7] LI Y, WEN Z, WEI Z, et al. Study on catalytic alkylation of benzene with methanol over ZSM-22 and ZSM-35[J]. China Petroleum Processing&Petrochemical Technology, 2017(4):38-46.
[8]季东,杜知松,王东亮,等. Nd/HZSM-5分子筛催化苯与甲醇烷基化的研究[J].分子催化, 2018, 32(1):27-34.JI Dong, DU Zhisong, WANG Dongliang, et al. Studies on alkylation of benzene with methanol catalyzed by Nd/HZSM-5 molecular sieve[J].Journal of Molecular Catalysis(China), 2018, 32(1):27-34.
[9] DONG P, LI Z, JI D, et al. Catalytic benzene mono-alkylation over three catalysts:improving activity and selectivity with M-Y catalyst[J].Journal of Inclusion Phenomena&Macrocyclic Chemistry, 2018, 90(1/2):149-155.
[10] DONG P, LI Z, WANG X, et al. The alkylation reaction of benzene with methanol to produce toluene:YC and Y-CCs catalyst[J]. Green Chemistry Letters and Reviews, 2018, 11(2):158-164.
[11] WANG Q T, HAN W W, HU H L, et al. Influence of the posttreatment of HZSM-5 zeolite on catalytic performance for alkylation of benzene with methanol[J]. Chinese Journal of Chemical Engineering,2017, 25(12):1777-1783.
[12]刘司,闻振浩,杨大强,等. HF改性的Pt/ZSM-5催化剂在苯和甲醇烷基化反应中的应用[J].应用化学, 2016, 33(5):571-576.LIU Si, WEN Zhenhao, YANG Daqiang, et al. Application of HF modified Pt/ZSM-5 catalyst in alkylation of benzene and methanol[J].Applied Chemistry, 2016, 33(5):571-576.
[13]赵博.改性纳米HZSM-5催化剂上苯和甲醇的烷基化[D].大连:大连理工大学, 2013.ZHAO Bo. Alkylation of benzene and methanol on modified nanoHZSM-5 catalyst[D]. Dalian:Dalian University of Technology, 2013.
[14]刘全昌.改性ZSM-5和MCM-49分子筛上苯与甲醇烷基化研究[D].北京:北京化工大学, 2013.LIU Quanchang. Alkylation of benzene with methanol on modified ZSM-5 and MCM-49 molecular sieves[D]. Beijing:Beijing University of Chemical Technology, 2013.
[15] SMIRNIOTTIS P G, RUCKENSTEIN E. Alkylation of benzene or toluene with MeOH or C2H4over ZSM-5 or beta zeolite:effect of the zeolite pore openings and of the hydrocarbons involved on the mechanism of alkylation[J]. Industrial&Engineering Chemistry Research, 1995, 34(5):1517-1528.
[16] ZHU Z, CHEN Q, XIE Z, et al. The roles of acidity and structure of zeolite for catalyzing toluene alkylation with methanol to xylene[J].Microporous&Mesoporous Materials, 2006, 88(1):16-21.
[17] ADEBAJO M O, HOWE R F, LONG M A. Methylation of benzene with methanol over zeolite catalysts in a low pressure flow reactor[J].Catalysis Today, 2000, 63(2):471-478.
[18] HU H, LYU J, CEN J, et al. Promoting effects of MgO and Pd modification on the catalytic performance of hierarchical porous ZSM-5 for catalyzing benzene alkylation with methanol[J]. RSC Advances,2015, 5(77):63044-63049.
[19]丁春华,王祥生,郭新闻.氧化物改性MCM-22上甲苯与甲醇的烷基化性能研究[J].石油学报(石油加工), 2007(5):38-42.DING Chunhua, WANG Xiangsheng, GUO Xinwen. Alkylation performance of toluene and methanol on oxide modified MCM-22[J].Acta Petrolei Sinica(Petroleum Processing), 2007(5):38-42.
[20] XUE B, LI Y, DENG L. Selective synthesis of p-xylene by alkylation of toluene with dimethyl carbonate over MgO-modified MCM-22[J].Catalysis Communications, 2010, 10(12):1609-1614.
[21]柯明,周慧云,周耀文. MCM-22分子筛改性研究进展[J].当代化工, 2015, 44(11):2629-2632, 2634.KE Ming, ZHOU Huiyun, ZHOU Yaowen. Research progress of MCM-22 molecular sieve modification[J]. Contemporary Chemical Industry,2015, 44(11):2629-2632, 2634.
[22] TAN W, LIU M, ZHAO Y, et al. Para-selective methylation of toluene with methanol over nano-sized ZSM-5 catalysts:synergistic effects of surface modifications with SiO2, P2O5, and MgO[J]. Microporous&Mesoporous Materials, 2014, 196:18-30.
[23]薛冰,吴浩,文琳智,等.硼酸改性MCM-22分子筛催化甲苯烷基化合成对二甲苯[J].化工进展, 2017, 36(6):2177-2182.XUE Bing, WU Hao, WEN Linzhi, et al. Boric acid modified MCM-22molecular sieve catalyzed toluene alkylation to synthesize p-xylene[J].Chemical Industry and Engineering Progress, 2017, 36(6):2177-2182.