H-ZSM-5分子筛硅铝比对其催化的甲醇转化丙烯选择性的影响（英文）
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摘要
本研究合成了一系列硅铝比不同(SiO_2/Al_2O_3=50-4000),但晶粒粒径相近的ZSM-5分子筛,并考察了硅铝比对甲醇转化反应丙烯选择性的影响。采用XRD、N_2吸附-脱附、NH_3-TPD和Py-FTIR方法对合成的HZSM-5分子筛进行物化性质表征。实验结果表明,随着硅铝比的增大,初始甲醇转化率降低,其中,硅铝比为50-1600的样品可以实现甲醇的完全转化。在甲醇完全转化的条件下,随着硅铝比的增大,丙烯选择性单调增加,从机理角度出发,揭示了甲醇转化制丙烯反应中,甲基化/裂化循环相较于甲基化/脱烷基化循环进行程度更大。此外,本研究提出了在甲醇完全转化条件下,保证最大丙烯选择性所需要的临界酸密度值([AS]_S),当甲醇进料量为0.162 g/min时,该临界值为0.175μmol/m~2。
A series of H-ZSM-5 zeolites with a silicon to aluminum ratio of 50-4000 but similar crystal size were synthesized and characterized by XRD,N2 sorption,NH3-TPD and Py-FTIR; the intrinsic effect of silicon to aluminum ratio on the selectivity to propene in the conversion of methanol to propene( M TP) was investigated. The results show that a complete conversion of methanol can be initially achieved over H-ZSM-5 with a silicon to aluminum ratio from 50 to 1600 and then the initial conversion of methanol decreases progressively with further increasing the silicon to aluminum ratio. M eanwhile,the selectivity to propene increases monotonically with an increase in the silicon to aluminum ratio of H-ZSM-5 for M TP with a complete methanol conversion,suggesting that a high Si/Al ratio for H-ZSM-5 may enhance the propagation of the alkene-based methylation/cracking cycle relative to the arene-based methylation/dealkylation cycle in M TP. A critical value of acid density,viz.,[AS]S,is required to achieve the maximum propene selectivity for M TP with a complete methanol conversion; this critical [AS]Svalue is 0. 175 μmol/m2 for the H-ZSM-5 zeolite under current reaction conditions.
A series of H-ZSM-5 zeolites with a silicon to aluminum ratio of 50-4000 but similar crystal size were synthesized and characterized by XRD,N2 sorption,NH3-TPD and Py-FTIR; the intrinsic effect of silicon to aluminum ratio on the selectivity to propene in the conversion of methanol to propene( M TP) was investigated. The results show that a complete conversion of methanol can be initially achieved over H-ZSM-5 with a silicon to aluminum ratio from 50 to 1600 and then the initial conversion of methanol decreases progressively with further increasing the silicon to aluminum ratio. M eanwhile,the selectivity to propene increases monotonically with an increase in the silicon to aluminum ratio of H-ZSM-5 for M TP with a complete methanol conversion,suggesting that a high Si/Al ratio for H-ZSM-5 may enhance the propagation of the alkene-based methylation/cracking cycle relative to the arene-based methylation/dealkylation cycle in M TP. A critical value of acid density,viz.,[AS]S,is required to achieve the maximum propene selectivity for M TP with a complete methanol conversion; this critical [AS]Svalue is 0. 175 μmol/m2 for the H-ZSM-5 zeolite under current reaction conditions.
引文
[1]MEI C,WEN P,LIU Z,LIU H,WANG Y,YANG W,XIE Z,HUA W,GAO Z.Selective production of propylene from methanol:M esoporosity development in high silica HZSM-5[J].J Catal,2008,258(1):243-249.
[2]LIU J,ZHANG C,SHEN Z,HUA W,TANG Y,SHEN W,YUE Y,XU H.Methanol to propylene:Effect of phosphorus on a high silica HZSM-5 catalyst[J].Catal Commun,2009,10(11):1506-1509.
[3]HUANG H,MENG X,CHEN C,ZHANG M,MENG Z,LI C,CUI Q.Effect of phosphorus addition on the performance of hierarchical ZSM-11 catalysts in methanol to propene reaction[J].Catal Lett,2016,146(11):2357-2363.
[4]SUN C,DU J,LIU J,YANG Y,REN N,SHEN W,XU H,TANG Y.A facile route to synthesize endurable mesopore containing ZSM-5catalyst for methanol to propylene reaction[J].Chem Commun,2010,46(15):2671-2673.
[5]ZHAO G,TENG J,XIE Z,JIN W,YANG W,CHEN Q,TANG Y.Effect of phosphorus on HZSM-5 catalyst for C4-olefin cracking reactions to produce propylene[J].J Catal,2007,248(1):29-37.
[6]CHEN J Q,BOZZANO A,GLOVER B,FUGLERUD T,KVISLE S.Recent advancements in ethylene and propylene production using the UOP/Hydro M TO process[J].Catal Today,2005,106(1/4):103-107.
[7]HICKMAN D A,SCHMIDT L D.Production of syngas by direct catalytic oxidation of methane[J].Science,1993,259(5093):343-346.
[8]ASADULLAH M,ITO S,KUNIMORI K,YAMADA M,TOMISHIGE K.Biomass gasification to hydrogen and syngas at low temperature:Novel catalytic system using fluidized-bed reactor[J].J Catal,2002,208(2):255-259.
[9]WU W,GUO W,XIAO W,LUO M.Dominant reaction pathway for methanol conversion to propene over high silicon H-ZSM-5[J].Chem Eng Sci,2011,66(20):4722-4732.
[10]CHANG C D,SILVESTRI A J.The conversion of methanol and other O-compounds to hydrocarbons over zeolite catalysts[J].J Catal,1977,47(2):249-259.
[11]YANG Y,SUN C,DU J,YUE Y,HUA W,ZHANG C,SHEN W,XU H.The synthesis of endurable B-Al-ZSM-5 catalysts with tunable acidity for methanol to propylene reaction[J].Catal Commun,2012,24:44-47.
[12]LEE Y J,KIM Y W,VISWANADHAM N,JUN K W,BAE J W.Novel aluminophosphate(AlPO)bound ZSM-5 extrudates with improved catalytic properties for methanol to propylene(M TP)reaction[J].Appl Catal A:Gen,2010,374(1/2):18-25.
[13]ROSTAMIZADEH M,TAEB A.Highly selective Me-ZSM-5 catalyst for methanol to propylene(MTP)[J].J Ind Eng Chem,2015,27:297-306.
[14]OLSBYE U,SVELLE S,BJRGEN M,BEATO P,JANSSENS T V W,JOENSEN F,BORDIGA S,LILLERUD K P.Conversion of methanol to hydrocarbons:How zeolite cavity and pore size controls product selectivity[J].Angew Chem Int Ed,2012,51(24):5810-5831.
[15]MENG X,YU Q,GAO Y,ZHANG Q,LI C,CUI Q.Enhanced propene/ethene selectivity for methanol conversion over pure silica zeolite:Role of hydrogen-bonded silanol groups[J].Catal Commun,2015,61:67-71.
[16]HU S,GONG Y,XU Q,LIU X,ZHANG Q,ZHANG L,DOU T.Highly selective formation of propylene from methanol over high-silica EU-1 zeolite catalyst[J].Catal Commun,2012,28:95-99.
[17]CHANG C D,CHU C T W,SOCHA R F.Methanol conversion to olefins over ZSM-5:I.Effect of temperature and zeolite SiO2Al2O3[J].J Catal,1984,86(2):289-296.
[18]ZHU Q,KONDO J N,SETOYAMA T,YAMAGUCHI M,DOMEN K,TATSUMI T.Activation of hydrocarbons on acidic zeolites:Superior selectivity of methylation of ethene with methanol to propene on weakly acidic catalysts[J].Chem Commun,2008,(41):5164-5166.
[19]ZHU Q,KONDO J N,YOKOI T,SETOYAMA T,YAMAGUCHI M,TAKEWAKI T,DOMEN K,TATSUMI T.The influence of acidities of boron-and aluminium-containing M FI zeolites on co-reaction of methanol and ethene[J].Phys Chem Chem Phys,2011,13(32):14598-14605.
[20]HASSANPOUR S,TAGHIZADEH M,YARIPOUR F.Preparation,characterization,and activity evaluation of H-ZSM-5 catalysts in vaporphase methanol dehydration to dimethyl ether[J].Ind Eng Chem Res,2010,49(9):4063-4069.
[21]FATHI S,SOHRABI M,FALAMAKI C.Improvement of HZSM-5 performance by alkaline treatments:Comparative catalytic study in the M TG reactions[J].Fuel,2014,116:529-537.
[22]WAN Z,WU W,LI G,WANG C,YANG H,ZHANG D.Effect of SiO2/Al2O3ratio on the performance of nanocrystal ZSM-5 zeolite catalysts in methanol to gasoline conversion[J].Appl Catal A:Gen,2016,523:312-320.
[23]MICHELS N L,MITCHELL S,PEREZ-RAMIREZ J.Effects of binders on the performance of shaped hierarchical MFI zeolites in methanolto-hydrocarbons[J].ACS Catal,2014,4(8):2409-2417.
[24]ZHANG C,WU Q,LEI C,PAN S,BIAN C,WANG L,MENG X,XIAO F S.Solvent-free and mesoporogen-free synthesis of mesoporous aluminosilicate ZSM-5 zeolites with superior catalytic properties in the methanol-to-olefins reaction[J].Ind Eng Chem Res,2017,56(6):1450-1460.
[25]WEI R,LI C,YANG C,SHAN H.Effects of ammonium exchange and Si/Al ratio on the conversion of methanol to propylene over a novel and large partical size ZSM-5[J].J Nat Gas Chem,2011,20(3):261-265.
[26]EMEIS C A.Determination of integrated molar extinction coefficients for infrared absorption bands of pyridine adsorbed on solid acid catalysts[J].J Catal,1993,141(2):347-354.
[27]BENITO P L,GAYUBO A G,AGUAYO A T,OLAZAR M,BILBAO J.Effect of Si/Al ratio and of acidity of H-ZSM5 zeolites on the primary products of methanol to gasoline conversion[J].J Chem Technol Biot,1996,66(2):183-191.
[28]PARRY E P.An infrared study of pyridine adsorbed on acidic solids.Characterization of surface acidity[J].J Catal,1963,2(5):371-379.
[29]OTHMAN I,MOHAMED R M,IBRAHIM I A,MOHAMED M M.Synthesis and modification of ZSM-5 with manganese and lanthanum and their effects on decolorization of indigo carmine dye[J].Appl Catal A:Gen,2006,299:95-102.
[30]FIROOZI M,BAGHALHA M,ASADI M.The effect of micro and nano particle sizes of H-ZSM-5 on the selectivity of MTP reaction[J].Catal Commun,2009,10(12):1582-1585.
[31]CAMPBELL S M,BIBBY D M,CODDINGTON J M,HOWE R F.Dealumination of HZSM-5 zeolites:II.Methanol to gasoline conversion[J].J Catal,1996,161(1):350-358.
[32]ST?CKER M.Methanol-to-hydrocarbons:Catalytic materials and their behavior1[J].Microporous Mesoporous Mater,1999,29(1/2):3-48.
[33]BJ?RGEN M,SVELLE S,JOENSEN F,NERLOV J,KOLBOE S,BONINO F,PALUMBOC L,BORDIGAC S,OLSBYE U.Conversion of methanol to hydrocarbons over zeolite H-ZSM-5:On the origin of the olefinic species[J].J Catal,2007,249(2):195-207.
[34]HAW J F,SONG W G,MARCUD D M,NICHOLAS J B.The mechanism of methanol to hydrocarbon catalysis[J].Acc Chem Res,2003,36(5):317-326.
[35]BJ?RGEN M,JOENSEN F,LILLERUD K P,OLSBYE U,SVELLE S.The mechanisms of ethene and propene formation from methanol over high silica H-ZSM-5 and H-beta[J].Catal Today,2009,142(1/2):90-97.
[36]SVELLE S,JOENSEN F,NERLOV J,OLSBYE U,LILLERUD K P,KOLBOE S,BJRGEN M.Conversion of methanol into hydrocarbons over zeolite H-ZSM-5:Ethene formation is mechanistically separated from the formation of higher alkenes[J].J Am Chem Soc,2006,128(46):14770-14771.
[37]SVELLE S,OLSBYE U,JOENSEN F,BJRGEN M.Conversion of methanol to alkenes over medium-and large-pore acidic zeolites:Steric manipulation of the reaction intermediates governs the ethene/propene product selectivity[J].J Phys Chem C,2007,111(49):17981-17984.
[38]SVELLE S,R?NNING P O,KOLBOE S.Kinetic studies of zeolite-catalyzed methylation reactions:1.Coreaction of[12C]ethene and[13C]methanol[J].J Catal,2004,224(1):115-123.
[39]SVELLE S,R?NNING P O,OLSBYE U,KOLBOE S.Kinetic studies of zeolite-catalyzed methylation reactions.Part 2.Co-reaction of[12C]propene or[12C]n-butene and[13C]methanol[J].J Catal,2005,234(2):385-400.
[40]HILL I M,AL HASHIMI S,BHAN A.Kinetics and mechanism of olefin methylation reactions on zeolites[J].J Catal,2012,285(1):115-123.
[41]HILL I M,NG Y S,BHAN A.Kinetics of butene isomer methylation with dimethyl ether over zeolite catalysts[J].ACS Catal,2012,2(8):1742-1748.
[42]SUN X,MULLER S,SHI H,HALLER G L,SANCHEZ-SANCHEZ M,VAN VEEN A C,LERCHER J A.On the impact of co-feeding aromatics and olefins for the methanol-to-olefins reaction on HZSM-5[J].J Catal,2014,314:21-31.
[43]ILIAS S,KHARE R,MALEK A,BHAN A.A descriptor for the relative propagation of the aromatic-and olefin-based cycles in methanol-tohydrocarbons conversion on H-ZSM-5[J].J Catal,2013,303:135-140.
[44]KHARE R,LIU Z,HAN Y,BHAN A.A mechanistic basis for the effect of aluminum content on ethene selectivity in methanol-tohydrocarbons conversion on HZSM-5[J].J Catal,2017,348:300-305.
[2]LIU J,ZHANG C,SHEN Z,HUA W,TANG Y,SHEN W,YUE Y,XU H.Methanol to propylene:Effect of phosphorus on a high silica HZSM-5 catalyst[J].Catal Commun,2009,10(11):1506-1509.
[3]HUANG H,MENG X,CHEN C,ZHANG M,MENG Z,LI C,CUI Q.Effect of phosphorus addition on the performance of hierarchical ZSM-11 catalysts in methanol to propene reaction[J].Catal Lett,2016,146(11):2357-2363.
[4]SUN C,DU J,LIU J,YANG Y,REN N,SHEN W,XU H,TANG Y.A facile route to synthesize endurable mesopore containing ZSM-5catalyst for methanol to propylene reaction[J].Chem Commun,2010,46(15):2671-2673.
[5]ZHAO G,TENG J,XIE Z,JIN W,YANG W,CHEN Q,TANG Y.Effect of phosphorus on HZSM-5 catalyst for C4-olefin cracking reactions to produce propylene[J].J Catal,2007,248(1):29-37.
[6]CHEN J Q,BOZZANO A,GLOVER B,FUGLERUD T,KVISLE S.Recent advancements in ethylene and propylene production using the UOP/Hydro M TO process[J].Catal Today,2005,106(1/4):103-107.
[7]HICKMAN D A,SCHMIDT L D.Production of syngas by direct catalytic oxidation of methane[J].Science,1993,259(5093):343-346.
[8]ASADULLAH M,ITO S,KUNIMORI K,YAMADA M,TOMISHIGE K.Biomass gasification to hydrogen and syngas at low temperature:Novel catalytic system using fluidized-bed reactor[J].J Catal,2002,208(2):255-259.
[9]WU W,GUO W,XIAO W,LUO M.Dominant reaction pathway for methanol conversion to propene over high silicon H-ZSM-5[J].Chem Eng Sci,2011,66(20):4722-4732.
[10]CHANG C D,SILVESTRI A J.The conversion of methanol and other O-compounds to hydrocarbons over zeolite catalysts[J].J Catal,1977,47(2):249-259.
[11]YANG Y,SUN C,DU J,YUE Y,HUA W,ZHANG C,SHEN W,XU H.The synthesis of endurable B-Al-ZSM-5 catalysts with tunable acidity for methanol to propylene reaction[J].Catal Commun,2012,24:44-47.
[12]LEE Y J,KIM Y W,VISWANADHAM N,JUN K W,BAE J W.Novel aluminophosphate(AlPO)bound ZSM-5 extrudates with improved catalytic properties for methanol to propylene(M TP)reaction[J].Appl Catal A:Gen,2010,374(1/2):18-25.
[13]ROSTAMIZADEH M,TAEB A.Highly selective Me-ZSM-5 catalyst for methanol to propylene(MTP)[J].J Ind Eng Chem,2015,27:297-306.
[14]OLSBYE U,SVELLE S,BJRGEN M,BEATO P,JANSSENS T V W,JOENSEN F,BORDIGA S,LILLERUD K P.Conversion of methanol to hydrocarbons:How zeolite cavity and pore size controls product selectivity[J].Angew Chem Int Ed,2012,51(24):5810-5831.
[15]MENG X,YU Q,GAO Y,ZHANG Q,LI C,CUI Q.Enhanced propene/ethene selectivity for methanol conversion over pure silica zeolite:Role of hydrogen-bonded silanol groups[J].Catal Commun,2015,61:67-71.
[16]HU S,GONG Y,XU Q,LIU X,ZHANG Q,ZHANG L,DOU T.Highly selective formation of propylene from methanol over high-silica EU-1 zeolite catalyst[J].Catal Commun,2012,28:95-99.
[17]CHANG C D,CHU C T W,SOCHA R F.Methanol conversion to olefins over ZSM-5:I.Effect of temperature and zeolite SiO2Al2O3[J].J Catal,1984,86(2):289-296.
[18]ZHU Q,KONDO J N,SETOYAMA T,YAMAGUCHI M,DOMEN K,TATSUMI T.Activation of hydrocarbons on acidic zeolites:Superior selectivity of methylation of ethene with methanol to propene on weakly acidic catalysts[J].Chem Commun,2008,(41):5164-5166.
[19]ZHU Q,KONDO J N,YOKOI T,SETOYAMA T,YAMAGUCHI M,TAKEWAKI T,DOMEN K,TATSUMI T.The influence of acidities of boron-and aluminium-containing M FI zeolites on co-reaction of methanol and ethene[J].Phys Chem Chem Phys,2011,13(32):14598-14605.
[20]HASSANPOUR S,TAGHIZADEH M,YARIPOUR F.Preparation,characterization,and activity evaluation of H-ZSM-5 catalysts in vaporphase methanol dehydration to dimethyl ether[J].Ind Eng Chem Res,2010,49(9):4063-4069.
[21]FATHI S,SOHRABI M,FALAMAKI C.Improvement of HZSM-5 performance by alkaline treatments:Comparative catalytic study in the M TG reactions[J].Fuel,2014,116:529-537.
[22]WAN Z,WU W,LI G,WANG C,YANG H,ZHANG D.Effect of SiO2/Al2O3ratio on the performance of nanocrystal ZSM-5 zeolite catalysts in methanol to gasoline conversion[J].Appl Catal A:Gen,2016,523:312-320.
[23]MICHELS N L,MITCHELL S,PEREZ-RAMIREZ J.Effects of binders on the performance of shaped hierarchical MFI zeolites in methanolto-hydrocarbons[J].ACS Catal,2014,4(8):2409-2417.
[24]ZHANG C,WU Q,LEI C,PAN S,BIAN C,WANG L,MENG X,XIAO F S.Solvent-free and mesoporogen-free synthesis of mesoporous aluminosilicate ZSM-5 zeolites with superior catalytic properties in the methanol-to-olefins reaction[J].Ind Eng Chem Res,2017,56(6):1450-1460.
[25]WEI R,LI C,YANG C,SHAN H.Effects of ammonium exchange and Si/Al ratio on the conversion of methanol to propylene over a novel and large partical size ZSM-5[J].J Nat Gas Chem,2011,20(3):261-265.
[26]EMEIS C A.Determination of integrated molar extinction coefficients for infrared absorption bands of pyridine adsorbed on solid acid catalysts[J].J Catal,1993,141(2):347-354.
[27]BENITO P L,GAYUBO A G,AGUAYO A T,OLAZAR M,BILBAO J.Effect of Si/Al ratio and of acidity of H-ZSM5 zeolites on the primary products of methanol to gasoline conversion[J].J Chem Technol Biot,1996,66(2):183-191.
[28]PARRY E P.An infrared study of pyridine adsorbed on acidic solids.Characterization of surface acidity[J].J Catal,1963,2(5):371-379.
[29]OTHMAN I,MOHAMED R M,IBRAHIM I A,MOHAMED M M.Synthesis and modification of ZSM-5 with manganese and lanthanum and their effects on decolorization of indigo carmine dye[J].Appl Catal A:Gen,2006,299:95-102.
[30]FIROOZI M,BAGHALHA M,ASADI M.The effect of micro and nano particle sizes of H-ZSM-5 on the selectivity of MTP reaction[J].Catal Commun,2009,10(12):1582-1585.
[31]CAMPBELL S M,BIBBY D M,CODDINGTON J M,HOWE R F.Dealumination of HZSM-5 zeolites:II.Methanol to gasoline conversion[J].J Catal,1996,161(1):350-358.
[32]ST?CKER M.Methanol-to-hydrocarbons:Catalytic materials and their behavior1[J].Microporous Mesoporous Mater,1999,29(1/2):3-48.
[33]BJ?RGEN M,SVELLE S,JOENSEN F,NERLOV J,KOLBOE S,BONINO F,PALUMBOC L,BORDIGAC S,OLSBYE U.Conversion of methanol to hydrocarbons over zeolite H-ZSM-5:On the origin of the olefinic species[J].J Catal,2007,249(2):195-207.
[34]HAW J F,SONG W G,MARCUD D M,NICHOLAS J B.The mechanism of methanol to hydrocarbon catalysis[J].Acc Chem Res,2003,36(5):317-326.
[35]BJ?RGEN M,JOENSEN F,LILLERUD K P,OLSBYE U,SVELLE S.The mechanisms of ethene and propene formation from methanol over high silica H-ZSM-5 and H-beta[J].Catal Today,2009,142(1/2):90-97.
[36]SVELLE S,JOENSEN F,NERLOV J,OLSBYE U,LILLERUD K P,KOLBOE S,BJRGEN M.Conversion of methanol into hydrocarbons over zeolite H-ZSM-5:Ethene formation is mechanistically separated from the formation of higher alkenes[J].J Am Chem Soc,2006,128(46):14770-14771.
[37]SVELLE S,OLSBYE U,JOENSEN F,BJRGEN M.Conversion of methanol to alkenes over medium-and large-pore acidic zeolites:Steric manipulation of the reaction intermediates governs the ethene/propene product selectivity[J].J Phys Chem C,2007,111(49):17981-17984.
[38]SVELLE S,R?NNING P O,KOLBOE S.Kinetic studies of zeolite-catalyzed methylation reactions:1.Coreaction of[12C]ethene and[13C]methanol[J].J Catal,2004,224(1):115-123.
[39]SVELLE S,R?NNING P O,OLSBYE U,KOLBOE S.Kinetic studies of zeolite-catalyzed methylation reactions.Part 2.Co-reaction of[12C]propene or[12C]n-butene and[13C]methanol[J].J Catal,2005,234(2):385-400.
[40]HILL I M,AL HASHIMI S,BHAN A.Kinetics and mechanism of olefin methylation reactions on zeolites[J].J Catal,2012,285(1):115-123.
[41]HILL I M,NG Y S,BHAN A.Kinetics of butene isomer methylation with dimethyl ether over zeolite catalysts[J].ACS Catal,2012,2(8):1742-1748.
[42]SUN X,MULLER S,SHI H,HALLER G L,SANCHEZ-SANCHEZ M,VAN VEEN A C,LERCHER J A.On the impact of co-feeding aromatics and olefins for the methanol-to-olefins reaction on HZSM-5[J].J Catal,2014,314:21-31.
[43]ILIAS S,KHARE R,MALEK A,BHAN A.A descriptor for the relative propagation of the aromatic-and olefin-based cycles in methanol-tohydrocarbons conversion on H-ZSM-5[J].J Catal,2013,303:135-140.
[44]KHARE R,LIU Z,HAN Y,BHAN A.A mechanistic basis for the effect of aluminum content on ethene selectivity in methanol-tohydrocarbons conversion on HZSM-5[J].J Catal,2017,348:300-305.