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

HUANG Hui-wen; ZHU Hui; ZHANG Shan-he; ZHANG Qiang; LI Chun-yi

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

中国石油大学(华东) 重质油国家重点实验室, 山东青岛 266580

基金项目:

the National 973 Program of China 2012CB215006

Research Fund for the Doctoral Programme of Higher Education 14CX06035A

详细信息

中图分类号: TQ536.9
计量
- 文章访问数: 107
- HTML全文浏览量: 52
- PDF下载量: 10
- 被引次数: 0
出版历程
- 收稿日期: 2018-10-09
- 修回日期: 2018-11-14
- 网络出版日期: 2021-01-23
- 刊出日期: 2019-01-10

Effect of silicon to aluminum ratio on the selectivity to propene in methanol conversion over H-ZSM-5 zeolites

State Key Laboratory of Heavy Oil Processing, China University of Petroleum(East China), Qingdao 266580, China

Funds:

the National 973 Program of China 2012CB215006

Research Fund for the Doctoral Programme of Higher Education 14CX06035A

More Information

Corresponding author: LI Chun-yi, E-mail:chuyli@upc.edu.cn

摘要

摘要: 本研究合成了一系列硅铝比不同（SiO₂/Al₂O₃=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、N₂吸附-脱附、NH₃-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0.162g/min时，该临界值为0.175μmol/m²。
- 甲醇 /
- 丙烯 /
- H-ZSM-5分子筛 /
- 硅铝比 /
- 酸性质
Abstract: 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 (MTP) 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. Meanwhile, the selectivity to propene increases monotonically with an increase in the silicon to aluminum ratio of H-ZSM-5 for MTP 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 MTP. A critical value of acid density, viz., [AS]_S, is required to achieve the maximum propene selectivity for MTP with a complete methanol conversion; this critical[AS]_S value is 0.175 μmol/m² for the H-ZSM-5 zeolite under current reaction conditions.
- methanol /
- propene /
- H-ZSM-5 /
- silicon to aluminum ratio /
- catalytic acidity

HTML全文

下载: 全尺寸图片幻灯片

Figure 1 XRD patterns of the H-ZSM-5 zeolites with different SiO₂/Al₂O₃ ratios

下载: 全尺寸图片幻灯片

Figure 2 NH₃-TPD profiles of the H-ZSM-5 zeolites with different SiO₂/Al₂O₃ ratios

下载: 全尺寸图片幻灯片

Figure 3 Methanol conversion (●/■), catalyst weight (1/2/3) and total acidity (0.003-0.419) of the H-ZSM-5 zeolites as a function of SiO₂/Al₂O₃ ratio (reaction conditions: 723 K, 0.1 MPa, WHSV= 9.72 h^-1)

下载: 全尺寸图片幻灯片

Figure 4 Selectivity to propene and ethene and the C₂⁼/2MBu ratio for MTP over the H-ZSM-5 zeolites with different SiO₂/Al₂O₃ ratios

下载: 全尺寸图片幻灯片

Figure 5 Proposed reaction pathways for methanol conversion over the H-ZSM-5 zeolites^[33]

下载: 全尺寸图片幻灯片

Figure 6 Methanol conversion (◆) and propene selectivity (●) as a function of acid density

下载: 全尺寸图片幻灯片

Table 1 Textural properties and relative crystallinity of the H-ZSM-5 zeolites with different SiO₂/Al₂O₃ ratios

Sample	Surface area ^a A/(m²·g^-1)			Pore volume ^a v/(cm³·g^-1)			Crystal size ^b d/nm	Relative crystallinity^c /%
Sample	total	micro	external	total	micro	meso	Crystal size ^b d/nm	Relative crystallinity^c /%
HZ-5(50)	416.9	338.1	78.8	0.21	0.16	0.05	73	90.4
HZ-5(100)	416.7	340.6	76.1	0.23	0.14	0.09	70	92.9
HZ-5(200)	416.9	337.0	79.9	0.21	0.16	0.05	69	93.3
HZ-5(400)	429.3	334.7	94.6	0.22	0.15	0.07	66	97.3
HZ-5(800)	415.9	318.3	97.7	0.22	0.14	0.08	68	98.8
HZ-5(1600)	428.9	328.3	100.6	0.21	0.14	0.07	69	98.6
HZ-5(2400)	417.2	308.6	108.6	0.22	0.14	0.09	71	98.0
HZ-5(3200)	421.8	306.6	115.2	0.21	0.13	0.08	68	96.8
HZ-5(4000)	419.2	337.3	81.9	0.22	0.16	0.07	70	100.0
^a : surface area was obtained by the BET method; the micropore surface area and volume were determined by the t-plot method; total pore volume was estimated from the nitrogen adsorption at p/p₀ = 0.99; the external surface area and mesopore volume were the difference between the total calculated value and the corresponding micropore data; ^b : crystal size was estimated by Scherrer's method from the XRD patterns using the diffraction peak at about 7.9°; ^c : relative crystallinity was estimated by comparing the XRD peak intensities at 2θ of 8.0°-9.0° and 22°-25° with those of the reference HZ-5 (4000) sample

下载: 导出CSV

Table 2 Acidity of H-ZSM-5 zeolites with different SiO₂/Al₂O₃ ratios

Sample	Acidity ^a /(mmol·g^-1)				Strong/weak^a	B/L ^b
Sample	weak	medium	strong	total	Strong/weak^a	B/L ^b
HZ-5(50)	0.214	0.091	0.114	0.419	0.534	0.588
HZ-5(100)	0.101	0.046	0.076	0.223	0.756	0.168
HZ-5(200)	0.036	0.022	0.030	0.088	0.867	0.097
HZ-5(400)	0.016	0.011	0.014	0.041	0.906	0.015
HZ-5(800)	0.007	0.005	0.009	0.021	1.363	0.014
HZ-5(1600)	0.003	-	0.009	0.012	3.029	0.013
HZ-5(2400)	0.001	-	0.004	0.005	2.538	0.013
HZ-5(3200)	0.001	-	0.003	0.004	1.342	0.015
HZ-5(4000)	0.001	-	0.002	0.003	0.748	0.041
^a : the amounts of weak, medium, and strong acid sites were calculated from the NH₃-TPD profiles by integrating the ammonia desorption lines in the range of 373-500, 500-600, and 600-923 K, respectively; ^b: the ratio of Brønsted to Lewis (B/L) acidity is obtained by comparing the band at 1550 cm^-1 to that at 1455 cm^-1 in the Py-FTIR spectra

下载: 导出CSV

Table 3 Methanol conversion, product distribution and C₄ hydrogen transfer index of for MTP over H-ZSM-5 zeolites with different SiO₂/Al₂O₃ ratios

Sample	Conversion x/%	Yield w/%							C₄-HTI
Sample	Conversion x/%	CH₄	C_2-5⁰	C₂⁼	C₃⁼	C₄⁼	C₅⁼	C₆₊	C₄-HTI
HZ-5(50)	99.99	5.22	55.33	13.37	16.89	6.38	0.89	0.91	0.76
HZ-5(100)	99.97	4.86	43.75	17.74	22.85	8.58	1.24	0.51	0.68
HZ-5(200)	99.97	3.27	28.56	20.51	31.53	13.05	1.50	1.30	0.51
HZ-5(400)	99.92	1.72	19.60	18.33	40.00	17.74	2.13	0.29	0.37
HZ-5(800)	99.75	1.09	8.59	12.90	52.01	21.84	2.86	0.45	0.17
HZ-5(1600)	99.54	1.52	3.15	8.33	58.60	22.89	3.91	1.08	0.06
HZ-5(2400)	93.21	1.01	2.91	7.03	58.31	20.40	3.23	0.23	0.07
HZ-5(3200)	89.50	3.75	2.83	7.72	42.84	22.45	9.31	0.44	0.05
HZ-5(4000)	77.37	5.64	3.35	5.58	31.21	20.31	10.20	0.86	0.06

下载: 导出CSV

参考文献(44)

[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:Mesoporosity development in high silica HZSM-5[J]. J Catal, 2008, 258(1):243-249. doi: 10.1016/j.jcat.2008.06.019
[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. doi: 10.1016/j.catcom.2009.04.004
[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. doi: 10.1007/s10562-016-1867-6
[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-5 catalyst for methanol to propylene reaction[J]. Chem Commun, 2010, 46(15):2671-2673. doi: 10.1039/b925850g
[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. doi: 10.1016/j.jcat.2007.02.027
[6]	CHEN J Q, BOZZANO A, GLOVER B, FUGLERUD T, KVISLE S. Recent advancements in ethylene and propylene production using the UOP/Hydro MTO process[J]. Catal Today, 2005, 106(1/4):103-107. http://www.sciencedirect.com/science/article/pii/S0920586105005195
[7]	HICKMAN D A, SCHMIDT L D. Production of syngas by direct catalytic oxidation of methane[J]. Science, 1993, 259(5093):343-346. doi: 10.1126/science.259.5093.343
[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. doi: 10.1006/jcat.2002.3575
[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. doi: 10.1016/j.ces.2011.06.036
[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. doi: 10.1016/0021-9517(77)90172-5
[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. doi: 10.1016/j.catcom.2012.03.013
[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 (MTP) reaction[J]. Appl Catal A:Gen, 2010, 374(1/2):18-25. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=489c5044660d8e94c2c9a6ec9ff4f0d4
[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. doi: 10.1016/j.jiec.2015.01.004
[14]	OLSBYE U, SVELLE S, BJØRGEN 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. doi: 10.1002/anie.201103657
[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. doi: 10.1016/j.catcom.2014.12.011
[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. doi: 10.1016/j.catcom.2012.08.011
[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. doi: 10.1016/0021-9517(84)90374-9
[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. doi: 10.1039/b809718f
[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 MFI zeolites on co-reaction of methanol and ethene[J]. Phys Chem Chem Phys, 2011, 13(32):14598-14605. doi: 10.1039/c1cp20338j
[20]	HASSANPOUR S, TAGHIZADEH M, YARIPOUR F. Preparation, characterization, and activity evaluation of H-ZSM-5 catalysts in vapor-phase methanol dehydration to dimethyl ether[J]. Ind Eng Chem Res, 2010, 49(9):4063-4069. doi: 10.1021/ie9013869
[21]	FATHI S, SOHRABI M, FALAMAKI C. Improvement of HZSM-5 performance by alkaline treatments:Comparative catalytic study in the MTG reactions[J]. Fuel, 2014, 116:529-537. doi: 10.1016/j.fuel.2013.08.036
[22]	WAN Z, WU W, LI G, WANG C, YANG H, ZHANG D. Effect of SiO₂/Al₂O₃ ratio on the performance of nanocrystal ZSM-5 zeolite catalysts in methanol to gasoline conversion[J]. Appl Catal A:Gen, 2016, 523:312-320. doi: 10.1016/j.apcata.2016.05.032
[23]	MICHELS N L, MITCHELL S, PEREZ-RAMIREZ J. Effects of binders on the performance of shaped hierarchical MFI zeolites in methanol-to-hydrocarbons[J]. ACS Catal, 2014, 4(8):2409-2417. doi: 10.1021/cs500353b
[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. doi: 10.1021/acs.iecr.7b00062
[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. doi: 10.1016/S1003-9953(10)60198-3
[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. doi: 10.1006/jcat.1993.1145
[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. doi: 10.1002/(ISSN)1097-4660
[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. doi: 10.1016/0021-9517(63)90102-7
[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. doi: 10.1016/j.apcata.2005.10.016
[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. doi: 10.1016/j.catcom.2009.04.021
[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. doi: 10.1006/jcat.1996.0192
[32]	STØCKER M. Methanol-to-hydrocarbons:Catalytic materials and their behavior1[J]. Microporous Mesoporous Mater, 1999, 29(1/2):3-48. http://d.old.wanfangdata.com.cn/Periodical/rlhxxb201205011
[33]	BJØRGEN 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. doi: 10.1016/j.jcat.2007.04.006
[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. doi: 10.1021/ar020006o
[35]	BJØRGEN 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. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=d44715c411115d671895ca3bfe9fd9d8
[36]	SVELLE S, JOENSEN F, NERLOV J, OLSBYE U, LILLERUD K P, KOLBOE S, BJØRGEN 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. doi: 10.1021/ja065810a
[37]	SVELLE S, OLSBYE U, JOENSEN F, BJØRGEN 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. doi: 10.1021/jp077331j
[38]	SVELLE S, RØNNING 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. doi: 10.1016/j.jcat.2004.02.022
[39]	SVELLE S, RØNNING 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. doi: 10.1016/j.jcat.2005.06.028
[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. doi: 10.1016/j.jcat.2011.09.018
[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. doi: 10.1021/cs300317p
[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. doi: 10.1016/j.jcat.2014.03.013
[43]	ILIAS S, KHARE R, MALEK A, BHAN A. A descriptor for the relative propagation of the aromatic-and olefin-based cycles in methanol-to-hydrocarbons conversion on H-ZSM-5[J]. J Catal, 2013, 303:135-140. doi: 10.1016/j.jcat.2013.03.021
[44]	KHARE R, LIU Z, HAN Y, BHAN A. A mechanistic basis for the effect of aluminum content on ethene selectivity in methanol-to-hydrocarbons conversion on HZSM-5[J]. J Catal, 2017, 348:300-305. doi: 10.1016/j.jcat.2017.02.022