Cu-SSZ-13的合成与金属改性及催化MTO性能
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摘要
以低廉的铜氨络合物(Cu-TEPA)为模板剂,通过原位水热合成法制备了Cu-SSZ-13。考察了两种铜盐和氢氧化钠用量对Cu-SSZ-13的晶相结构和形貌的影响,测试了两种铜盐制备的Cu-SSZ-13和金属改性的Cu-SSZ-13在甲醇制烯烃(MTO)中的催化性能。用XRF、XRD、SEM、N2等温吸附脱附(BET)和NH3程序升温脱附(NH3-TPD)对催化剂进行了表征。结果表明:碱度对Cu-SSZ-13的结晶度有很大影响,较高或较低的碱度会导致方沸石杂晶的产生,甚至生成纯相方沸石,n(Na2O)∶n(Al2O3)的较佳值为4.7~5;在MTO反应中,硝酸铜制备的CuSSZ-13的氢转移反应剧烈,反应初期丙烷选择性达到40%,远高于硫酸铜制备的Cu-SSZ-13的丙烷选择性(19%),因此,在抑制副反应发生上,Cu-SSZ-13/Cu SO4要优于Cu-SSZ-13/Cu(NO3)2。锰改性的Cu-SSZ-13明显提高了抗积炭失活能力,在反应温度440℃、质量空速(WHSV)5 h-1条件下,催化寿命从未改性的30 min延长到了65 min。
Molecular sieve Cu-SSZ-13 was synthesized by in situ hydrothermal method using a low-cost copper amine complex(Cu-TEPA) as a template. The effects of two copper salts and dosage of sodium hydroxide on the crystal phase and morphological of the obtained Cu-SSZ-13 were studied. Besides,the catalytic performance of Cu-SSZ-13 prepared with two copper salts and metal modified Cu-SSZ-13 for methanol to olefins(MTO) was evaluated. These catalysts were characterized by XRF,XRD,SEM,BET and NH3-TPD techniques. The results showed that alkalinity had a great influence on the crystallinity of Cu-SSZ-13. If the alkalinity was excessively high or low,analcime zeolite as an impurity or pure phase would be produced. During the reaction of MTO,hydrogen transfer reaction of Cu-SSZ-13 prepared with cupric nitrate was intense,and the propane selectivity reached 40% in the early stage of the reaction,far higher than that of Cu-SSZ-13 prepared with cupric sulfate(19%),therefore,Cu-SSZ-13/Cu SO4 was superior to Cu-SSZ-13/Cu(NO3)2on inhibiting side reaction. Cu-SSZ-13 modified with manganese exhibited an obvious inhibition of coking deactivation,its lifetime extended from 30 to 65 min at 440 ℃and WHSV 5 h-1.
Molecular sieve Cu-SSZ-13 was synthesized by in situ hydrothermal method using a low-cost copper amine complex(Cu-TEPA) as a template. The effects of two copper salts and dosage of sodium hydroxide on the crystal phase and morphological of the obtained Cu-SSZ-13 were studied. Besides,the catalytic performance of Cu-SSZ-13 prepared with two copper salts and metal modified Cu-SSZ-13 for methanol to olefins(MTO) was evaluated. These catalysts were characterized by XRF,XRD,SEM,BET and NH3-TPD techniques. The results showed that alkalinity had a great influence on the crystallinity of Cu-SSZ-13. If the alkalinity was excessively high or low,analcime zeolite as an impurity or pure phase would be produced. During the reaction of MTO,hydrogen transfer reaction of Cu-SSZ-13 prepared with cupric nitrate was intense,and the propane selectivity reached 40% in the early stage of the reaction,far higher than that of Cu-SSZ-13 prepared with cupric sulfate(19%),therefore,Cu-SSZ-13/Cu SO4 was superior to Cu-SSZ-13/Cu(NO3)2on inhibiting side reaction. Cu-SSZ-13 modified with manganese exhibited an obvious inhibition of coking deactivation,its lifetime extended from 30 to 65 min at 440 ℃and WHSV 5 h-1.
引文
[1]Nan H M,Wen Y S,Wu X Z,et al.Recent development of methanol to olefins technology[J].Modern Chemical Industry,2014,34(7):41-46.
[2]Wu X Z.Latest progress of coal to light olefins industrial demonstration project[J].Chemical Industry&Engineering Progress,2014,33(4):787-794.
[3]Tian P,Wei Y,Ye M,et al.Methanol to olefins(MTO):from fundamentals to commercialization[J].Acs Catalysis,2015,5(3):1922-1938.
[4]Yang Bo(杨博),Guo Cuili(郭翠梨),Cheng Jingyao(程景耀).Progress in synthesis and application of SSZ-13 zeolite[J].Chemical Engineering Progress(化工进展),2014,33(2):368-373.
[5]Zhu Q J,Kondo J N,Tatsumi T,et al.A comparative study of methanol to olefin over CHA and MTF zeolites[J].The Journal of Physical Chemistry C,2007,111(14):5409-5415.
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[7]Chen B H,Xu R N,Zhang R D,et al.Economical way to synthesize SSZ-13 with abundant ion-exchanged Cu+for an extraordinary performance in selective catalytic reduction(SCR)of NOxby ammonia[J].Environmental Science&Technology,2014,48(23):13909-13916.
[8]Xu R N,Zhang R D,Liu N,et al.Template design and economical strategy for the synthesis of SSZ-13(CHA-type)zeolite as an excellent catalyst for the selective catalytic reduction of NOxby ammonia[J].Chem Cat Chem,2015,7(23):841-852.
[9]Wang X,Wu Q M,Chen C Y,et al.Atom-economical synthesis of a high silica CHA zeolite using a solvent-free route[J].Chemical Communications,2015,51(95):16920-16923.
[10]Ren L M,Zhang Y B,Zeng S J,et al.Design and synthesis of a catalytically active Cu-SSZ-13 zeolite from a copper-amine complex template[J].Chinese Journal of Catalysis,2012,33(1):92-105.
[11]Kwak J H,Tonkyn R G,Kim D H,et al.Excellent activity and selectivity of Cu-SSZ-13 in the selective catalytic reduction of NOxwith NH3[J].Journal of Catalysis,2010,275(2):187-190.
[12]Mc Ewen J S,Anggara T,Schneider W F,et al.Integrated operando X-ray absorption and DFT characterization of Cu-SSZ-13exchange sites during the selective catalytic reduction of NOxwith NH3[J].Catalysis today,2012,184(1):129-144.
[13]Xie L J,Liu F D,Ren L M,et al.Excellent performance of onepot synthesized Cu-SSZ-13 catalyst for the selective catalytic reduction of NOxwith NH3[J].Environmental Science&Technology,2013,48(1):566-572.
[14]Su Yu(苏玉),Li Yuan(李渊),Deng Yunshui(邓云水),et al.Cu-SSZ-13 molecular sieve catalyst for methanol-to-olefins[J].Petrochemical Technology(石油化工),2013,42(10):1075-1079.
[15]Peng Zhaoliang(彭兆亮).The optimization on in situ synthesis conditions of Cu-SSZ-13 denitration catalyst[D].Taiyuan:Taiyuan University of Technology,2015.
[16]Liu Guangyu(刘广宇),Tian Peng(田鹏),Liu Zhongmin(刘中民).Modification of SAPO-34 molecular sieve used for methanol to olefins reaction[J].Progress in Chemistry(化学进展),2010,22(8):1531-1537.
[17]Guan Xinxin(关新新),Liu Kecheng(刘克成),Wu Guangjun(武光军),et al.Nitridation of SAPO-34 molecular sieve and its application in methanol transform into olefins[J].Journal of Molecular Catalysis(分子催化),2006,20(3):270-272.
[18]Bleken F,Bjrgen M,Palumbo L,et al.The effect of acid strength on the conversion of methanol to olefins over acidic microporous catalysts with the CHA topology[J].Topics in Catalysis,2009,52(3):218-228.
[19]Aghaei E,Haghighi M.High temperature synthesis of nanostructured Ce-SAPO-34 catalyst used in conversion of methanol to light olefins:effect of temperature on physicochemical properties and catalytic performance[J].Journal of Porous Materials,2015,22(1):187-200.
[20]Wang Xingwang(王兴旺),Li Shihong(李世洪),Sun Yan(孙岩),et al.Mn modified molecular sieve SAPO-34 and its catalytic performance[J].Modern Chemical Industry(现代化工),2015,35(5):85-87.
[21]Li Hongbin(李红彬),Lv Jinzhao(吕金钊),Wang Yijing(王一婧),et al.Alkaline earth metals-modified SAPO-34 for methanol conversion to light olefins[J].Chinese Journal of Catalysis(催化学报),2009,30(6):509-513.
[22]Zones S I.Zeolite SSZ-13 and its method of preparation:US4544538[P].1985-10-01.
[23]Borade R B,Clearfield A.Synthesis of aluminum rich MCM-41[J].Catalysis Letters,1995,31(2/3):267-272.
[2]Wu X Z.Latest progress of coal to light olefins industrial demonstration project[J].Chemical Industry&Engineering Progress,2014,33(4):787-794.
[3]Tian P,Wei Y,Ye M,et al.Methanol to olefins(MTO):from fundamentals to commercialization[J].Acs Catalysis,2015,5(3):1922-1938.
[4]Yang Bo(杨博),Guo Cuili(郭翠梨),Cheng Jingyao(程景耀).Progress in synthesis and application of SSZ-13 zeolite[J].Chemical Engineering Progress(化工进展),2014,33(2):368-373.
[5]Zhu Q J,Kondo J N,Tatsumi T,et al.A comparative study of methanol to olefin over CHA and MTF zeolites[J].The Journal of Physical Chemistry C,2007,111(14):5409-5415.
[6]Santilli D S,Zones S I.Selective conversion of methanol to low molecular weight olefins over high silica SSZ-13 zeolite:US4496786[P].1985-01-29.
[7]Chen B H,Xu R N,Zhang R D,et al.Economical way to synthesize SSZ-13 with abundant ion-exchanged Cu+for an extraordinary performance in selective catalytic reduction(SCR)of NOxby ammonia[J].Environmental Science&Technology,2014,48(23):13909-13916.
[8]Xu R N,Zhang R D,Liu N,et al.Template design and economical strategy for the synthesis of SSZ-13(CHA-type)zeolite as an excellent catalyst for the selective catalytic reduction of NOxby ammonia[J].Chem Cat Chem,2015,7(23):841-852.
[9]Wang X,Wu Q M,Chen C Y,et al.Atom-economical synthesis of a high silica CHA zeolite using a solvent-free route[J].Chemical Communications,2015,51(95):16920-16923.
[10]Ren L M,Zhang Y B,Zeng S J,et al.Design and synthesis of a catalytically active Cu-SSZ-13 zeolite from a copper-amine complex template[J].Chinese Journal of Catalysis,2012,33(1):92-105.
[11]Kwak J H,Tonkyn R G,Kim D H,et al.Excellent activity and selectivity of Cu-SSZ-13 in the selective catalytic reduction of NOxwith NH3[J].Journal of Catalysis,2010,275(2):187-190.
[12]Mc Ewen J S,Anggara T,Schneider W F,et al.Integrated operando X-ray absorption and DFT characterization of Cu-SSZ-13exchange sites during the selective catalytic reduction of NOxwith NH3[J].Catalysis today,2012,184(1):129-144.
[13]Xie L J,Liu F D,Ren L M,et al.Excellent performance of onepot synthesized Cu-SSZ-13 catalyst for the selective catalytic reduction of NOxwith NH3[J].Environmental Science&Technology,2013,48(1):566-572.
[14]Su Yu(苏玉),Li Yuan(李渊),Deng Yunshui(邓云水),et al.Cu-SSZ-13 molecular sieve catalyst for methanol-to-olefins[J].Petrochemical Technology(石油化工),2013,42(10):1075-1079.
[15]Peng Zhaoliang(彭兆亮).The optimization on in situ synthesis conditions of Cu-SSZ-13 denitration catalyst[D].Taiyuan:Taiyuan University of Technology,2015.
[16]Liu Guangyu(刘广宇),Tian Peng(田鹏),Liu Zhongmin(刘中民).Modification of SAPO-34 molecular sieve used for methanol to olefins reaction[J].Progress in Chemistry(化学进展),2010,22(8):1531-1537.
[17]Guan Xinxin(关新新),Liu Kecheng(刘克成),Wu Guangjun(武光军),et al.Nitridation of SAPO-34 molecular sieve and its application in methanol transform into olefins[J].Journal of Molecular Catalysis(分子催化),2006,20(3):270-272.
[18]Bleken F,Bjrgen M,Palumbo L,et al.The effect of acid strength on the conversion of methanol to olefins over acidic microporous catalysts with the CHA topology[J].Topics in Catalysis,2009,52(3):218-228.
[19]Aghaei E,Haghighi M.High temperature synthesis of nanostructured Ce-SAPO-34 catalyst used in conversion of methanol to light olefins:effect of temperature on physicochemical properties and catalytic performance[J].Journal of Porous Materials,2015,22(1):187-200.
[20]Wang Xingwang(王兴旺),Li Shihong(李世洪),Sun Yan(孙岩),et al.Mn modified molecular sieve SAPO-34 and its catalytic performance[J].Modern Chemical Industry(现代化工),2015,35(5):85-87.
[21]Li Hongbin(李红彬),Lv Jinzhao(吕金钊),Wang Yijing(王一婧),et al.Alkaline earth metals-modified SAPO-34 for methanol conversion to light olefins[J].Chinese Journal of Catalysis(催化学报),2009,30(6):509-513.
[22]Zones S I.Zeolite SSZ-13 and its method of preparation:US4544538[P].1985-10-01.
[23]Borade R B,Clearfield A.Synthesis of aluminum rich MCM-41[J].Catalysis Letters,1995,31(2/3):267-272.