Octanes in alkylation products obtained from industrial alkylation were studied by batch experiments. More than eight octane isomers were identified and quantified by gas chromatography-mass spectrometry. Based on a classic carbenium ion mechanism, the carbocation transition states in concentrated sulfuric acid catalyzed alkylation were investigated using quantum-chemical simulations and predicted the concentration and octane isomerization products including trimethylpentane and dimethylhexane as well as the formation of heavier compounds that resulted from the oligomerization of octane and butene. The agreement between model calculations and experimental data was quite satisfactory. Calculation results indicated that composition and content of trimethylpentanes in the alkylation products were 2,2,4-trimethylpentane>2,3,3-trimethylpentane>2,3,4-trimethylpentane>2,2,3-trimethylpentane whether the 2-butene or i-butene acts as olefin. Heavier compounds in the alkylate were primarily formed by the oligomerization of dimethylhexane with 1-butene. Hopefully, the carbocation transition state models developed in this work will be useful for understanding the product distributions of octane in alkylation products.
G A Olah, G K S Prakash, B Török, M Török. Effect of acid/hydrocarbon ratio, temperature and contact time on the isobutane-isobutylene alkylation with trifluoromethanesulfonic acid. Catalysis Letters, 1996, 40(3): 137–142 https://doi.org/10.1007/BF00815273
2
E N Ivashkina, E D Ivanchina, A E Nurmakanova, S S Boychenko, A S Ushakov, I O Dolganova. Mathematical modeling sulfuric acid catalyzed alkylation of isobutane with olefins. Procedia Engineering, 2016, 152: 81–86 https://doi.org/10.1016/j.proeng.2016.07.632
3
H Wang, X Z Meng, G Y Zhao, S J Zhang. Isobutane/butene alkylation catalyzed by ionic liquids: a more sustainable process for clean oil production. Green Chemistry, 2017, 19(6): 1462–1489 https://doi.org/10.1039/C6GC02791A
4
S W Liu, S Tan, B Bian, H L Yu, Q Wu, Z G Liu, F L Yu, L Li, S T Yu, X Y Song, Z Song. Isobutane/2-butene alkylation catalyzed by BrønstedLewis acidic ionic liquids. RSC Advances, 2018, 8(35): 19551–19559 https://doi.org/10.1039/C8RA03485K
5
P X Gan, S W Tang. Research progress in ionic liquids catalyzed isobutane/butene alkylation. Chinese Journal of Chemical Engineering, 2016, 24(11): 1497–1504 https://doi.org/10.1016/j.cjche.2016.03.005
6
W Z Sun, Y Shi, J Chen, Z H Xi, L Zhao. Alkylation kinetics of isobutane by C4 olefins using sulfuric acid as catalyst. Industrial & Engineering Chemistry Research, 2013, 52(44): 15262–15269 https://doi.org/10.1021/ie400415p
7
L M Lee, P Harriott. The kinetics of isobutane alkylation in sulfuric acid. Industrial & Engineering Chemistry Process Design and Development, 1977, 16(3): 282–287 https://doi.org/10.1021/i260063a006
8
K W Li, R E Eckert, L F Albright. Alkylation of isobutane with light olefins using sulfuric acid. operating variables affecting physical phenomena only. Industrial & Engineering Chemistry Process Design and Development, 1970, 9(3): 434–446 https://doi.org/10.1021/i260035a011
9
A Feller, I Zuazo, A O Guzman, J O Barth, J A Lercher. Common mechanistic aspects of liquid and solid acid catalyzed alkylation of isobutane with n-butene. Journal of Catalysis, 2003, 216(41): 313–323 https://doi.org/10.1016/S0021-9517(02)00068-4
10
G M Santana, A Akgerman. Alkylation of isobutane with 1-butene on a solid acid catalyst in supercritical reaction media. Industrial & Engineering Chemistry Research, 2001, 40(18): 3879–3882 https://doi.org/10.1021/ie000501t
11
F L Yu, Y L Gu, Q C Liu, C X Xie. Alkylation of isobutane and isobutene in acidic polyether ionic liquids. China Petroleum Processing and Petrochemical Technology, 2019, 21(3): 29–35
M Boronat, P Viruela, A Corma. Theoretical study of the mechanism of branching rearrangement of carbenium ions. Applied Catalysis A, General, 1996, 146(1): 207–223 https://doi.org/10.1016/0926-860X(96)00160-3
14
Z C Liu, X H Meng, R Zhang, C M Xu, H Dong, Y F Hu. Reaction performance of isobutane alkylation catalyzed by a composite ionic liquid at a short contact time. AIChE Journal. American Institute of Chemical Engineers, 2014, 60(6): 2244–2253 https://doi.org/10.1002/aic.14394
15
Y Liu, L H Wang, R Li, R S Hu. Reaction mechanism of ionic liquid catalyzed alkylation: alkylation of 2-butene with deuterated isobutene. Journal of Molecular Catalysis A Chemical, 2016, 421: 29–36 https://doi.org/10.1016/j.molcata.2016.05.005
16
T L T B Bui, W Korth, S Aschauer, A Jess. Alkylation of isobutane with 2-butene using ionic liquids as catalyst. Green Chemistry, 2009, 11(12): 1961–1967 https://doi.org/10.1039/b913872b
17
S V Nayak, P A Ramachandran, M P Dudukovic. Modeling of key reaction pathways: zeolite catalyzed alkylation processes. Chemical Engineering Science, 2010, 65(1): 335–342 https://doi.org/10.1016/j.ces.2009.06.048
18
C Liu, R van Santen, A Poursaeinesfahani, T J H Vlugt, E A Pidko, E J M Hensen. Hydride transfer versus deprotonation kinetics in the isobutane-propene alkylation reaction: a computational study. ACS Catalysis, 2017, 7(12): 8613–8627 https://doi.org/10.1021/acscatal.7b02877
19
P Wang, D X Wang, C M Xu, J S Gao. DFT calculations of the alkylation reaction mechanisms of isobutane and 2-butene catalyzed by Brönsted acids. Applied Catalysis A, General, 2007, 332(1): 22–26 https://doi.org/10.1016/j.apcata.2007.07.043
20
L F Albright, M A Spalding, J Faunce, R E Eckert. Alkylation of isobutane with C4 olefins. 3. Two-step process using sulfuric acid as catalyst. Industrial & Engineering Chemistry Research, 1988, 27(3): 391–397 https://doi.org/10.1021/ie00075a005
21
E Ivashkina, I Dolganova, I Dolganov, E Ivanchina, A Nurmakanova, A Bekker. Modeling the H2SO4-catalyzed isobutane alkylation with alkenes considering the process unsteadiness. Catalysis Today, 2019, 329: 206–213 https://doi.org/10.1016/j.cattod.2018.11.076
22
L F Albright, L Houle, A M Sumutka, R E Eckert. Alkylation of isobutane with butenes: effect of sulfuric acid compositions. Industrial & Engineering Chemistry Process Design and Development, 1972, 11(3): 446–450 https://doi.org/10.1021/i260043a020
23
L F Albright, A E Kranz. Alkylation of isobutane with pentenes using sulfuric acid as a catalyst: chemistry and reaction mechanisms. Industrial & Engineering Chemistry Research, 1992, 31(2): 475–481 https://doi.org/10.1021/ie00002a004
24
W Z Zheng, D Li, W Z Sun, L Zhao. Multi-scale modeling of isobutane alkylation with 2-butene using composite ionic liquids as catalyst. Chemical Engineering Science, 2018, 186: 209–218 https://doi.org/10.1016/j.ces.2018.04.043
25
P Wang, D Wang, C M Xu, J J Liu, J S Gao. Ab initio calculations on the mechanism of isobutane and 2-butene alkylation reaction catalyzed by hydrofluoric acid. Catalysis Today, 2007, 125(3-4): 263–269 https://doi.org/10.1016/j.cattod.2007.04.003
26
K I Patrylak, L K Patrylak, I A Repetskyi. Mechanisms of alkylation of isobutane by butenes and H/D exchange in isobutane molecules on acid zeolites. Theoretical and Experimental Chemistry, 2013, 49(3): 143–157 https://doi.org/10.1007/s11237-013-9308-8
27
T Hamzehlouyan, M Kazemeini, F Khorasheh. Modeling of catalyst deactivation in zeolite-catalyzed alkylation of isobutane with 2-butene. Chemical Engineering Science, 2010, 65(2): 645–650 https://doi.org/10.1016/j.ces.2009.08.022
28
A E Koklin, V M K Chan, V I Bogdan. Conversion of isobutane-butenes mixtures on H-USY and SO2–4/ZrO2 catalysts under supercritical conditions: isobutane alkylation and butenes oligomerization. Russian Journal of Physical Chemistry B, 2014, 8(8): 991–998 https://doi.org/10.1134/S1990793114080089
29
V B Kazansky, T V Vasina. Suggestion on a new alternative mechanism of the sulfuric acid catalyzed isioparaffin-olefin alkylation. Studies in Surface Science and Catalysis, 2000, 130: 251–256 https://doi.org/10.1016/S0167-2991(00)80965-9
30
D A Zhurko, M V Frash, V B Kazansky. A quantum-chemical study of the formation mechanism and nature of tert-butyl carbenium ions in 100% sulfuric acid. Catalysis Letters, 1998, 55(1): 7–14 https://doi.org/10.1023/A:1019089602834
31
W Z Sun, W Z Zheng, P Cao, L Zhao. Probing interfacial behaviors of Brønsted acidic ionic liquids improved isobutane alkylation with C4 olefin catalyzed by sulfuric acid. Chemical Engineering Journal, 2019, 377: 119744 https://doi.org/10.1016/j.cej.2018.08.130
32
W Z Zheng, P Cao, Y Yuan, C Z Huang, Z N Wang, W Z Sun, L Zhao. Experimental and modeling study of isobutane alkylation with C4 olefin catalyzed by Brønsted acidic ionic liquid/sulfuric acid. Chemical Engineering Journal, 2019, 377: 119578 https://doi.org/10.1016/j.cej.2018.07.180
33
V B Kazansky, M V Frash, R A van Santen. A quantum-chemical study of hydride transfer in catalytic transformations of paraffins on zeolites: pathways through adsorbed nonclassical carbonium ions. Catalysis Letters, 1997, 48(1/2): 61–67 https://doi.org/10.1023/A:1019066718512
34
S Prasad, D P Ojha. Computational study of molecular geometries, and vibrational characteristics of two liquid crystalline disubstituted biphenylcyclohexanes using ab-initio methods. Molecular Crystals and Liquid Crystals (Philadelphia, Pa.), 2019, 682(1): 27–43 https://doi.org/10.1080/15421406.2019.1655975
35
K Sathyamoorthy, P Vinothkumar, J Irshadahamed, P Muralimanohar, M Priya, J Liu. Synthesis, growth, structural, optical, electrical and magnetic properties of novel (E)-3-(4-(diethylamino) phenyl)-2-(thiophen-2-yl) acrylonitrile (DPTA) single crystal. Journal of Molecular Structure, 2019, 1192: 241–251 https://doi.org/10.1016/j.molstruc.2019.04.095
36
W Z Sun, W Z Zheng, W X Xie, L Zhao. Understanding structure-property relationship of SO3H-functionalized ionic liquids together with sulfuric acid in catalyzing isobutane alkylation with C4 olefin. Industrial & Engineering Chemistry Research, 2018, 57(45): 15310–15318 https://doi.org/10.1021/acs.iecr.8b03923
37
M J Janik, R J Davis, M Neurock. A density functional theory study of the alkylation of isobutane with butene over phosphotungstic acid. Journal of Catalysis, 2006, 244(1): 65–77 https://doi.org/10.1016/j.jcat.2006.08.013
38
H Ren, Q Y Zhang, X W Chen. Establishment and application of an automatic molecular simulation system. Journal of Northwestern Polytechnical University, 2006, 24(4): 448–452
39
L F Albright. Mechanism for alkylation of isobutane with light olefins. American Chemical Society, 1977, 22: 391–398
40
R J Shlegeris, L F Albright. Alkylation of isobutane with various olefins in the presence of sulfuric acid. Industrial & Engineering Chemistry Process Design and Development, 1969, 8(1): 92–98 https://doi.org/10.1021/i260029a016
41
A Feller, I Zuazo, A Guzman, J O Barth, J A Lercher. Common mechanistic aspects of liquid and solid acid catalyzed alkylation of isobutane with n-butene. ChemInform, 2003, 216(41): 313–323
42
C P Huang, Z C Liu, C M Xu, B H Chen, Y F Liu. Effects of additives on the properties of chloroaluminate ionic liquids catalyst for alkylation of isobutane and butene. Applied Catalysis A, General, 2004, 277(1-2): 41–43 https://doi.org/10.1016/j.apcata.2004.08.019
43
L F Albright, K W Li. Alkylation of isobutane with light olefins using sulfuric acid: reaction mechanism and comparison with HF alkylation. Industrial & Engineering Chemistry Process Design and Development, 1970, 9(3): 447–454 https://doi.org/10.1021/i260035a013
44
A E Nurmakanova, E N Ivashkina, E D Ivanchina, I A Dolganov, S S Boychenko. Predicting alkylate yield and its hydrocarbon composition for sulfuric acid catalyzed isobutane alkylation with olefins using the method of mathematical modeling. Procedia Chemistry, 2015, 15: 54–64 https://doi.org/10.1016/j.proche.2015.10.009
45
K Satoh, H Matsuhashi, K Arata. Alkylation to form trimethylpentanes from isobutane and 1-butene catalyzed by solid superacids of sulfated metal oxides. Applied Catalysis A, General, 1999, 189(1): 35–43 https://doi.org/10.1016/S0926-860X(99)00244-6
46
P Wang, D X Wang, C M Xu, J J Liu, J S Cao. Ab initio calculations on the mechanism of isobutane and 2-butene alkylation reaction catalyzed by hydrofluoric acid. Catalysis Today, 2007, 125(3-4): 263–269 https://doi.org/10.1016/j.cattod.2007.04.003