Effect of bimetallic catalysts on cracking behavior of coal tar model compounds

doi:10.11949/j.issn.0438-1157.20170517

Abstract

Abstract:

Four nickel based catalysts were prepared by mechanical chemical method,Al₂O₃ as carrier,Ce,Co and Fe as additives.The catalysts were characterized using XRD,H₂-TPR,BET and NH₃-TPD.The catalytic effects on cracking behavior of coal tar model compounds toluene and pyrene were investigated in a fixed-bed reactor under carrier gas flow rate of 50 ml·min^-1 and cracking temperature of 750℃.The experimental results showed that all four catalysts have higher ordered mesoporous structure and active species Ni mainly exists as NiAl₂O₄ spinel in the catalysts.In addition,acidic strength of catalyst with Fe additive was higher than that of Ni/Al₂O₃,while the opposite trend was observed in catalysts with Ce and Co additives.The cracking evaluation results showed that these additives have little effect on the cracking rate of heavy component pyrene,about 67% for all catalysts.However,Ce and Co additives were beneficial to carbon deposition resistance of catalysts,which carbon deposition,compared to none additive catalyst,was reduced by 28.8% and 18.0%,respectively.

Key words: bimetallic catalyst, model compound, fixed-bed, acidity

摘要：

以Al₂O₃为载体，Ce、Co和Fe为助剂，采用机械化学法制备了4种镍基催化剂，对其进行了XRD、H₂-TPR、BET、NH₃-TPD等表征。当载气流量为50 ml·min^-1，裂解温度为750℃时，在固定床反应器中考察了各催化剂对煤焦油模型化合物甲苯+芘裂解行为的影响。结果表明：4种催化剂均为介孔催化剂，且双金属催化剂的介孔有序度更高；催化剂中活性组分Ni主要以尖晶石NiAl₂O₄的形式存在；添加Fe助剂后，催化剂的酸强度较Ni/Al₂O₃增加，添加Ce和Co时则相反。评价实验表明，助剂对重质组分芘的裂解率影响较小，约为67%，然而Ce和Co对催化剂的抗积炭性能有利，其析碳分别较无助剂时降低28.8%和18.0%。

关键词: 双金属催化剂, 模型化合物, 固定床, 酸强度

CLC Number:

TQ241.5

ZHANG Yanmin, ZOU Da, ZHAO Yuan, ZHONG Mei, MA Fengyun. Effect of bimetallic catalysts on cracking behavior of coal tar model compounds[J]. CIESC Journal, 2017, 68(10): 3805-3815.

张艳敏, 邹达, 赵渊, 钟梅, 马凤云. 双金属催化剂对煤焦油模型化合物催化裂解行为的影响[J]. 化工学报, 2017, 68(10): 3805-3815.

References 30

[1]	高晋生. 煤的热解、炼焦和煤焦油加工[M]. 北京:化学工业出版社, 2010. GAO J S. The Coal Pyrolysis, Coke and Coal Tar Processing[M]. Beijing:Chemical Industry Press, 2001.
[2]	王向辉, 门卓武, 许明, 等. 低阶煤粉煤热解提质技术研究现状及发展建议[J]. 洁煤技术, 2014, 20(6):36-41. WANG X H, MEN Z W, XU M, et al. Research status and development proposals on pyrolysis techniques of low rank pulverized coal[J]. Clean Coal Technology, 2014, 20(6):36-41.
[3]	岑建孟, 方梦祥, 王勤辉, 等. 煤分级利用多联产技术及其发展前景[J]. 化工进展, 2011, 30(1):88-94. CEN J M, FANG M X, WANG Q H, et al. Development and prospect of coal staged conversion poly-generation technology[J]. Chemical Industry and Engineering Progress, 2011, 30(1):88-94.
[4]	QU X, LIANG P, WANG Z, et al. Pilot development of polygeneration process of circulating fluidized bed combustion combined with coal pyrolysis[J]. Chemical Engineering & Technology, 2011, 34(1):61-68.
[5]	LI C, SUZUKI K. Resources, properties and utilization of tar[J]. Resources, Conservation and Recycling, 2010, 54(11):905-915.
[6]	WANG J, LU X, YAO J, et al. Experimental study of coal yopping process in a downer reactor[J]. Industrial & Engineering Chemistry Research, 2005, 44(3):463-470.
[7]	LIANG P, WANG Z, BI J. Process characteristics investigation of simulated circulating fluidized bed combustion combined with coal pyrolysis[J]. Fuel Processing Technology, 2007, 88(1):23-28.
[8]	HAN J Z, WANG X D, YUE J R, et al. Catalytic upgrading of coal pyrolysis tar over char-based catalysts[J]. Fuel Processing Technology, 2014, 122:98-106.
[9]	艾馨鹏, 岳宝华, 汪学广, 等. Ni/MgO-Al2O3催化剂上高温焦油组分的催化转化[J]. 物理化学学报, 2009, 25(8):1517-1522. AI X P, YUE B H, WANG X G, et al. Catalytic conversion of tar components in hot coke oven gas over Ni/MgO-Al2O3 catalysts[J]. Acta Phys. Chim. Sin., 2009, 25(8):1517-1522.
[10]	LI L Y, KAYOKO M, HARUTO M, et al. Low-temperature gasification of a woody biomass under a nickel-loaded brown coal char[J]. Fuel Processing Technology, 2010, 91:889-894.
[11]	LI L, MORISHITA K, TAKARADA T. Conversion of hot coke oven gas into light fuel gas over Ni/Al2O3 catalyst[J]. J. Chem. Eng. Jpn., 2006, 39:461-468.
[12]	METTA C, TIPPANAKARIN B, JUMRAS L. Production of aromatic hydrocarbons from Mae-Moh lignite[J]. Fuel Processing Technology, 2002, 79:171-179.
[13]	HAN J, LIU X, YUE J, et al. Catalytic upgrading of in situ coal pyrolysis tar over Ni-char catalyst with different additives[J]. Energy & Fuels, 2014, 28(8):4934-4941.
[14]	ZHANG J, HUI W, DALAI A K. Development of stable bimetallic catalysts for carbon dioxide reforming of methane[J]. Journal of Catalysis, 2007, 249(2):300-310.
[15]	KEⅡCHI T, TAKEO K, JIN N, et al. Promoting effect of the interaction between Ni and CeO2 on steam gasification of biomass[J]. Catalysis Communications, 2007, 8:1074-1079.
[16]	YUAN H K, MA X H, XU Z L. Pore structure analysis of PFSA/SiO2 composite catalysts from nitrogen adsorption isotherms[J]. Science China Chemistry, 2011, 54(1):257-262.
[17]	莫文龙, 马凤云, 刘月娥, 等. 制备方法对Ni-Al2O3催化剂在CO2-CH4重整反应中催化性能的影响[J]. 燃料化学学报, 2015, 43(9):1083-1091. MO W L, MA F Y, LIU Y E, et al. Effect of preparation methods on the catalytic performance of Ni-Al2O3 for CO2-CH4 reforming[J]. Journal of Fuel Chemistry and Technology, 2015, 43(9):1083-1091.
[18]	莫文龙, 马凤云, 郝世豪, 等. 介孔Al2O3的制备及其在CO2-CH4重整镍基催化剂中的应用研究[J]. 天然气化工, 2014, 39(5):16-21. MO W L, MA F Y, HAO S H, et al. Preparation of ordered mesoporous Al2O3 and its application in Ni-based catalysts for CH4/CO2 reforming[J]. Natural Gas Chemical Industry, 2014, 39:16-21.
[19]	孟凡会, 刘军, 李忠, 等. Ce含量对Ni-Ce/Al2O3催化剂结构及浆态床CO甲烷化性能的影响[J]. 燃料化学学报, 2014, 42(2):231-237. MENG F H, LIU J, LI Z, et al. Effect of Ce content of Ni-Ce/Al2O3 catalyst on structure and CO methanation in slurry-bed reactor[J]. Fuel Chemistry and Technology, 2014, 42(2):231-237.
[20]	ASHOK J, KAWI S. Steam reforming of toluene as a biomass tar model compound over CeO2, promoted Ni/CaO-Al2O3, catalytic systems[J]. International Journal of Hydrogen Energy, 2013, 38(32):13938-13949.
[21]	ZHANG R Q, WANG Y C, ROBERT C. Steam reforming of tar compounds over Ni/olivine catalysts doped with CeO2[J]. Energy Conversion and Management, 2007, 48:68-77.
[22]	MO W L, MA F Y, LIU Y E, et al. Preparation of porous Al2O3 by template method and its application in Ni-based catalyst for CH4/CO2 reforming to produce syngas[J]. Int. J. Hydrogen Energy, 2015, 40:16147-16158.
[23]	张大洲, 李秀杰, 刘盛林, 等. 载体酸性对Mo/HZSM-5-Al2O3催化剂上烯烃歧化反应性能的影响[J]. 催化学报, 2011, 11:1747-1754. ZHANG D Z, LI X J, LIU S L, et al. Effects of support acidity on the catalytic performance of Mo/HZSM-5-Al2O3 catalysts in olefin metathesis[J]. Chinese Journal of Catalysis, 2011, 11:1747-1754.
[24]	MARAFI A, STAINSLAUS A, HAUSER A, et al. An investigation of the deactivation behavior of industrial Mo/Al2O3 and Ni-Mo/Al2O3 catalysts in hydrotreating Kuwait atmospheric residue[J]. Petroleum Science & Technology, 2005, 23(3/4):385-408.
[25]	LIU H, ZHANG L, LI X, et al. Production of propene from 1-butene metathesis reaction on tungsten based heterogeneous catalysts[J]. Energy Chemistry, 2009, 18(3):331-336.
[26]	YU F, YUE B, WANG X, et al. Hydrocracking of tar components from hot cole oven gas over a Ni/Ce-ZrO2/gamma-Al2O3 catalyst at atmospheric pressure[J]. 2009, 30(7):690-696.
[27]	LI L, FAN H J, HU H Q. A theoretical study on bond dissociation enthalpies of coal based model compounds[J]. Fuel, 2015, 153:70-77.
[28]	ZHANG T C, ZHANG L D, FAN H J, et al. An experimental and theoretical study of toluene with tunable synchrotron VUV photoionization and molecular-beam mass spectrometry[J]. Combustion and Flame, 2009, 153:2071-2083.
[29]	陈广辉, 李玉, 张长森, 等. CeO2对Ni-Cu/HZSM-5催化剂在生物油加氢脱氧反应中抗积炭性能的影响[J]. 燃料化学学报, 2017, (4):449-457. CHEN G H, LI Y, ZHANG C S, et al. Influence of CeO2 on the carbonaceous deposition behavior of Ni-Cu/HZSM-5 catalyst in the hydrodeoxygenation of bio-oil[J]. Journal of Fuel Chemistry and Technology, 2017, 45(4):449-457
[30]	VOGELAAR B M, LANGEVELD A D V, EIJSBOUTS S, et al. Analysis of coke deposition profiles in commercial spent hydroprocessing catalysts using Raman spectroscopy[J]. Fuel, 2007, 86(7/8):1122-1129.