Citation: LI Fu-chao, ZHANG Jiu-shun, YUAN Qi-min. Mechanism of methane formation in thermal and catalytic cracking of n-octane[J]. Journal of Fuel Chemistry and Technology, ;2014, 42(6): 697-703. shu

Mechanism of methane formation in thermal and catalytic cracking of n-octane

1.
Research Institute of Petroleum Processing, SINOPEC, Beijing 100083, China

Corresponding author: YUAN Qi-min,
Received Date: 15 October 2013
Available Online: 17 February 2014
Fund Project: 国家科技支撑计划(2012BAE05B01)。 (2012BAE05B01)

The thermal and catalytic cracking reactions of n-octane were carried out in a temperature range of 550~650 ℃ with low conversions (x<15%) in a pulse micro-reactor over quartz and ZRP zeolite. Reaction mechanism of methane formation was analyzed. The results showed that ethylene, propylene and n-butylene were primary products and four paths contributed to methane formation in thermal cracking of n-octane. At 600 ℃, dehydrogenation of terminal C-H bond in the chain attacked by methyl radical led to methane production. Due to higher activation energy of cleavage of terminal C-C bond in octyl radical formed via dehydrogenation of central C-C bond, only methane can form at higher temperature. Protolytic cracking was predominant with relatively remarkable yield of normal paraffin in catalytic cracking of n-octane over ZRP zeolite. Methane was produced by protolytic cracking route as well. By comparison of methane formation between thermal and protolytic cracking, it revealed that methane formed through protolytic cracking below 600 ℃ while thermal cracking dominated the selectivity of methane at higher reaction temperatures.
- n-octane,
- thermal cracking,
- catalytic cracking,
- methane,
- reaction path
1. [1]
  [1] RICE F O. The thermal decomposition of oganic compounds from the standpoint of free radicals. I. Saturated hydrocarbons[J]. J Am Chem Soc, 1931, 53(5): 1959-1972.
2. [2]
  [2] RICE F O. The thermal decomposition of organic compounds from the standpoint of free radicals. Ⅲ. The calculation of the products formed from paraffin hydrocarbons[J]. J Am Chem Soc, 1933, 55(7): 3035-3040.
3. [3]
  [3] RICE F O, DOOLEY M D. The thermal decomposition of organic compounds from the standpoint of free radicals. IV. The dehydrogenation of paraffin hydrocarbons and the strength of the C-C bond[J]. J Am Chem Soc, 1933, 55(10): 4245-4247.
4. [4]
  [4] KOSSIAKOFF A, RICE F O. Thermal decomposition of hydrocarbons, resonance stabilization and isomerization of free radicals[J]. J Am Chem Soc, 1943, 65(4): 590-595.
5. [5]
  [5] GREENSFELDER B, VOGE H, GOOD G. Catalytic cracking of pure hydrocarbons[J]. Ind Eng Chem, 1945, 37(12): 1168-1176.
6. [6]
  [6] HAAG W, DESSAU R. Duality of mechanism for acid-catalyzed paraffin cracking[C]//Proceedings of the 8th International Congress on Catalysis, Berlin, 1984.
7. [7]
  [7] YALURIS G, REKOSKE J E, APARICIO L M, MADON R J, DUMESIC J A. Isobutane cracking over Y-zeolites: I. Development of a kinetic-model[J]. J Catal, 1995, 153(1): 54-64.
8. [8]
  [8] YALURIS G, REKOSKE J E, APARICIO L M, MADON R J, DUMESIC J A. Isobutane cracking over Y-zeolites: Ⅱ. Catalytic cycles and reaction selectivity[J]. J Catal, 1995, 153(1): 65-75.
9. [9]
  [9] 胡晓燕, 李春义, 杨朝合. 正庚烷在HZSM-5催化剂上的催化裂解行为[J]. 物理化学学报, 2010, 26(12): 3291-3298. (HU Xiao-yan, LI Chun-yi, YANG Chao-he. Catalytic cracking behavior of n-heptane over HZSM-5 catalyst[J]. Acta Physico-Chimica Sinica, 2010, 26(12): 3291-3298.)
10. [10]
  [10] LUKYANOV D B, SHTRAL V I, KHADZHIEV S N. A kinetic model for the hexane cracking reaction over H-ZSM-5[J]. J Catal, 1994, 146(1): 87-92.
11. [11]
  [11] JUNG J S, PARK J W, SEO G. Catalytic cracking of n-octane over alkali-treated MFI zeolites[J]. Appl Catal A: Gen, 2005, 288(1/2): 149-157.
12. [12]
  [12] KISSIN Y V. Relative reactivities of alkanes in catalytic cracking reactions[J]. J Catal, 1990, 126(2): 600-609.
13. [13]
  [13] WIELERS A F H, VAARKAMP M, POST M F M. Relation between properties and performance of zeolites in paraffin cracking[J]. J Catal, 1991, 127(1): 51-66.
14. [14]
  [14] ALTWASSER S, WELKER C, TRAA Y, WEITKAMP J. Catalytic cracking of n-octane on small-pore zeolites[J]. Micropor Mesopor Mater, 2005, 83(1/3): 345-356.
15. [15]
  [15] RICE F O. Thermal decomposition of hydrocarbons and engine detonation[J]. Ind Eng Chem, 1934, 26(3): 259-262.
16. [16]
  [16] 徐如人, 庞文琴, 于吉红, 霍启升, 陈接胜. 分子筛与多孔材料化学[M]. 北京: 科学出版社, 2004: 63-65. (XU Ru-ren, PANG Wen-qin, YU Ji-hong, HUO Qi-sheng, CHEN Jie-sheng. Zeolite and porous materials[M]. Beijing: Science Press, 2004: 63-65.)
17. [17]
  [17] JOLLY S, SAUSSEY J, BETTAHAR M M, LAVALLEY J C, BENAZZI E. Reaction mechanisms and kinetics in the n-hexane cracking over zeolites[J]. Appl Catal A: Gen, 1997, 156(1): 71-96.
18. [18]
  [18] CORMA A, PLANELLES J, SÁNCHEZ-MARÍN J, TOMÁS F. The role of different types of acid site in the cracking of alkanes on zeolite catalysts[J]. J Catal, 1985, 93(1): 30-37.
19. [19]
  [19] WOJCIECHOWSKI B W. The reaction mechanism of catalytic cracking: Quantifying activity, selectivity, and catalyst decay[J]. Catal Rev, 1998, 40(3): 209-328.
20. [20]
  [20] SHERTUKDE P V, MARCELIN G, SILL G A, KEITH HALL W. Study of the mechanism of the cracking of small alkane molecules on HY Zeolites[J]. J Catal, 1992, 136(2): 446-462.
1. [1]
  Feifei Yang , Wei Zhou , Chaoran Yang , Tianyu Zhang , Yanqiang Huang . Enhanced Methanol Selectivity in CO₂ Hydrogenation by Decoration of K on MoS₂ Catalyst. Acta Physico-Chimica Sinica, 2024, 40(7): 2308017-0. doi: 10.3866/PKU.WHXB202308017
2. [2]
  Xue Liu , Lipeng Wang , Luling Li , Kai Wang , Wenju Liu , Biao Hu , Daofan Cao , Fenghao Jiang , Junguo Li , Ke Liu . Research on Cu-Based and Pt-Based Catalysts for Hydrogen Production through Methanol Steam Reforming. Acta Physico-Chimica Sinica, 2025, 41(5): 100049-0. doi: 10.1016/j.actphy.2025.100049
3. [3]
  Lina Guo , Ruizhe Li , Chuang Sun , Xiaoli Luo , Yiqiu Shi , Hong Yuan , Shuxin Ouyang , Tierui Zhang . Effect of Interlayer Anions in Layered Double Hydroxides on the Photothermocatalytic CO₂ Methanation of Derived Ni-Al₂O₃ Catalysts. Acta Physico-Chimica Sinica, 2025, 41(1): 100002-0. doi: 10.3866/PKU.WHXB202309002
4. [4]
  Wen YANG , Didi WANG , Ziyi HUANG , Yaping ZHOU , Yanyan FENG . La promoted hydrotalcite derived Ni-based catalysts: In situ preparation and CO₂ methanation performance. Chinese Journal of Inorganic Chemistry, 2024, 40(3): 561-570. doi: 10.11862/CJIC.20230276
5. [5]
  Wenlong Wang , Wentao Hao , Lang He , Jia Qiao , Ning Li , Chaoqiu Chen , Yong Qin . Bandgap and adsorption engineering of carbon dots/TiO₂ S-scheme heterojunctions for enhanced photocatalytic CO₂ methanation. Acta Physico-Chimica Sinica, 2025, 41(9): 100116-0. doi: 10.1016/j.actphy.2025.100116
6. [6]
  Yinuo Wang , Siran Wang , Yilong Zhao , Dazhen Xu . Selective Synthesis of Diarylmethyl Anilines and Triarylmethanes via Multicomponent Reactions: Introduce a Comprehensive Experiment of Organic Chemistry. University Chemistry, 2024, 39(8): 324-330. doi: 10.3866/PKU.DXHX202401063
7. [7]
  Yang Lv , Yingping Jia , Yanhua Li , Hexiang Zhong , Xinping Wang . Integrating the Ideological Elements with the “Chemical Reaction Heat” Teaching. University Chemistry, 2024, 39(11): 44-51. doi: 10.12461/PKU.DXHX202402059
8. [8]
  Ruming Yuan , Pingping Wu , Laiying Zhang , Xiaoming Xu , Gang Fu . Patriotic Devotion, Upholding Integrity and Innovation, Wholeheartedly Nurturing the New: The Ideological and Political Design of the Experiment on Determining the Thermodynamic Functions of Chemical Reactions by Electromotive Force Method. University Chemistry, 2024, 39(4): 125-132. doi: 10.3866/PKU.DXHX202311057
9. [9]
  Zhuo WANG , Junshan ZHANG , Shaoyan YANG , Lingyan ZHOU , Yedi LI , Yuanpei LAN . Preparation and photocatalytic performance of CeO₂-reduced graphene oxide by thermal decomposition. Chinese Journal of Inorganic Chemistry, 2024, 40(9): 1708-1718. doi: 10.11862/CJIC.20240067
10. [10]
  Yongqing Xu , Yuyao Yang , Mengna Wu , Xiaoxiao Yang , Xuan Bie , Shiyu Zhang , Qinghai Li , Yanguo Zhang , Chenwei Zhang , Robert E. Przekop , Bogna Sztorch , Dariusz Brzakalski , Hui Zhou . Review on Using Molybdenum Carbides for the Thermal Catalysis of CO₂ Hydrogenation to Produce High-Value-Added Chemicals and Fuels. Acta Physico-Chimica Sinica, 2024, 40(4): 2304003-0. doi: 10.3866/PKU.WHXB202304003
11. [11]
  Yang Xia , Kangyan Zhang , Heng Yang , Lijuan Shi , Qun Yi . Improving Photocatalytic H₂O₂ Production over iCOF/Bi₂O₃ S-Scheme Heterojunction in Pure Water via Dual Channel Pathways. Acta Physico-Chimica Sinica, 2024, 40(11): 2407012-0. doi: 10.3866/PKU.WHXB202407012
12. [12]
  Heng Zhang . Determination of All Rate Constants in the Enzyme Catalyzed Reactions Based on Michaelis-Menten Mechanism. University Chemistry, 2024, 39(4): 395-400. doi: 10.3866/PKU.DXHX202310047
13. [13]
  Yue Zhao , Yanfei Li , Tao Xiong . Copper Hydride-Catalyzed Nucleophilic Additions of Unsaturated Hydrocarbons to Aldehydes and Ketones. University Chemistry, 2024, 39(4): 280-285. doi: 10.3866/PKU.DXHX202309001
14. [14]
  Hong Lu , Yidie Zhai , Xingxing Cheng , Yujia Gao , Qing Wei , Hao Wei . Advancements and Expansions in the Proline-Catalyzed Asymmetric Aldol Reaction. University Chemistry, 2024, 39(5): 154-162. doi: 10.3866/PKU.DXHX202310074
15. [15]
  Guojie Xu , Fang Yu , Yunxia Wang , Meng Sun . Introduction to Metal-Catalyzed β-Carbon Elimination Reaction of Cyclopropenones. University Chemistry, 2024, 39(8): 169-173. doi: 10.3866/PKU.DXHX202401060
16. [16]
  Yuanyi Lu , Jun Zhao , Hongshuang Li . Silver-Catalyzed Ring-Opening Minisci Reaction: Developing a Teaching Experiment Suitable for Undergraduates. University Chemistry, 2024, 39(11): 225-231. doi: 10.3866/PKU.DXHX202401088
17. [17]
  Hongting Yan , Aili Feng , Rongxiu Zhu , Lei Liu , Dongju Zhang . Reexamination of the Iodine-Catalyzed Chlorination Reaction of Chlorobenzene Using Computational Chemistry Methods. University Chemistry, 2025, 40(3): 16-22. doi: 10.12461/PKU.DXHX202403010
18. [18]
  Aili Feng , Xin Lu , Peng Liu , Dongju Zhang . Computational Chemistry Study of Acid-Catalyzed Esterification Reactions between Carboxylic Acids and Alcohols. University Chemistry, 2025, 40(3): 92-99. doi: 10.12461/PKU.DXHX202405072
19. [19]
  Pengzi Wang , Wenjing Xiao , Jiarong Chen . Copper-Catalyzed C―O Bond Formation by Kharasch-Sosnovsky-Type Reaction. University Chemistry, 2025, 40(4): 239-244. doi: 10.12461/PKU.DXHX202406090
20. [20]
  Jiajie Li , Xiaocong Ma , Jufang Zheng , Qiang Wan , Xiaoshun Zhou , Yahao Wang . Recent Advances in In-Situ Raman Spectroscopy for Investigating Electrocatalytic Organic Reaction Mechanisms. University Chemistry, 2025, 40(4): 261-276. doi: 10.12461/PKU.DXHX202406117

Get Citation

PDF

XML

Metrics

PDF Downloads(0)
Abstract views(610)
HTML views(74)

通讯作者: 陈斌, bchen63@163.com

1.
沈阳化工大学材料科学与工程学院沈阳 110142