An investigation of the pyrolysis kinetics of American, Chinese and Estonian oil shales was conducted applying a non-isothermal thermogravimetric analysis (TGA). TGA weight loss curves clearly indicate that the pyrolysis of all oil shales tested is independent of their geographic origin, and is mainly taking place in the temperature range of 300 to 500 ºC. As expected, at temperatures above 700 ºC mass loss due to the decomposition of oil shale carbonates was detected, except for the Kentucky and Chinese 2 oil shale samples. The kinetic decomposition rate parameters such as activation energy and pre-exponential factor were calculated applying the Coats-Redfern integral and direct Arrhenius methods. Independent of the oil shale kerogen origin, pyrolysis occurs in two consecutive temperature zones with slightly dissimilar kinetic parameter values. The activation energy values obtained were in the range of 14 to 31 kJ/mol for the low and 70 to 149 kJ/mol for the high temperature zone.
1. Siirde, A. Oil shale – global solution or part of the problem? Oil Shale, 2008, 25(2), 201–202.
http://dx.doi.org/10.3176/oil.2008.2.01
2. Altun, N. E., Hicyilmaz, C., Hwang, J.-Y., Bagci, A. S., Kök, M. Oil shales in the world and Turkey; reserves, current situation and future prospects: a review. Oil Shale, 2006, 23(3), 211–227.
3. Konist, A., Loo, L., Valtsev, A., Maaten, B., Siirde, A., Neshumayev, D., Pihu, T. Calculation of the amount of Estonian oil shale products from combustion in regular and oxy-fuel mode in a CFB boiler. Oil Shale, 2014, 31(3), 211–224.
http://dx.doi.org/10.3176/oil.2014.3.02
4. Konist, A., Valtsev, A., Loo, L., Pihu, T., Liira, M., Kirsimäe, K. Influence of oxy-fuel combustion of Ca-rich oil shale fuel on carbonate stability and ash composition. Fuel, 2015, 139, 671–677.
http://dx.doi.org/10.1016/j.fuel.2014.09.050
5. Torrente, M. C., Galán, M. C. Kinetics of the thermal decomposition of oil shale from Puertollano (Spain). Fuel, 2001, 80(3), 327–334.
http://dx.doi.org/10.1016/S0016-2361(00)00101-0
6. Lille, Ü. Current knowledge on the origin and structure of Estonian kukersite kerogen. Oil Shale, 2003, 20(3), 253–263.
7. Hutton, A., Bharati, S., Robl, T. Chemical and petrographic classification of kerogen/macerals. Energ. Fuel., 1994, 8(6), 1478–1488.
http://dx.doi.org/10.1021/ef00048a038
8. Yan, F., Song, Y. Properties estimation of main oil shale in China. Energ. Source. Part A, 2009, 31(4), 372–376.
http://dx.doi.org/10.1080/15567030701530347
9. Külaots, I., Goldfarb, J. L., Suuberg, E. M. Characterization of Chinese, American and Estonian oil shale semicokes and their sorptive potential. Fuel, 2010, 89(11), 3300–3306.
http://dx.doi.org/10.1016/j.fuel.2010.05.025
10. Tiwari, P., Deo, M. Detailed kinetic analysis of oil shale pyrolysis TGA data. AIChE J., 2012, 58(2), 505–515.
http://dx.doi.org/10.1002/aic.12589
11. Wang, Z., Deng, S., Gu, Q., Zhang, Y., Cui, X., Wang, H. Pyrolysis kinetic study of Huadian oil shale, spent oil shale and their mixtures by thermogravimetric analysis. Fuel Process. Technol., 2013, 110, 103–108.
http://dx.doi.org/10.1016/j.fuproc.2012.12.001
12. Bai, F., Sun, Y., Liu, Y., Liu, B., Guo, M., Lü, X., Guo, W., Li, Q., Hou, C., Wang, Q. Kinetic investigation on partially oxidized Huadian oil shale by thermogravimetric analysis. Oil Shale, 2014, 31(4), 377–393.
http://dx.doi.org/10.3176/oil.2014.4.06
13. Liu, Q. Q., Han, X. X., Li, Q. Y., Huang, Y. R., Jiang, X. M. TG–DSC analysis of pyrolysis process of two Chinese oil shales. J. Therm. Anal. Calorim., 2014, 116(1), 511–517.
http://dx.doi.org/10.1007/s10973-013-3524-2
14. Jaber, J. O., Probert, S. D. Non-isothermal thermogravimetry and decomposition kinetics of two Jordanian oil shales under different processing conditions. Fuel Process. Technol., 2000, 63(1), 57–70.
http://dx.doi.org/10.1016/S0378-3820(99)00064-8
15. Rajeshwar, K. The kinetics of the thermal decomposition of Green River oil shale kerogen by non-isothermal thermogravimetry. Thermochim. Acta, 1981, 45(3), 253–263.
http://dx.doi.org/10.1016/0040-6031(81)85086-1
16. Williams, P. T., Ahmad, N. Investigation of oil-shale pyrolysis processing conditions using thermogravimetric analysis. Appl. Energ., 2000, 66(2), 113–133.
http://dx.doi.org/10.1016/S0306-2619(99)00038-0
17. Fang-Fang, X., Ze, W., Wei-Gang, L., Wen-Li, S. Study on thermal conversion of Huadian oil shale under N2 and CO2 atmospheres. Oil Shale, 2010, 27(4), 309–320.
http://dx.doi.org/10.3176/oil.2010.4.04
18. Aboulkas, A., El Harfi, K. Study of the kinetics and mechanisms of thermal decomposition of Moroccan Tarfaya oil shale and its kerogen. Oil Shale, 2008, 25(4), 426–443.
http://dx.doi.org/10.3176/oil.2008.4.04
19. Thakur, D. S., Nuttall, H. E., Cha, C. Y. The kinetics of the thermal decomposition of Moroccan oil shale by thermogravimetry. Prepr. Pap. Am. Chem. Soc., Div. Fuel Chem., 1982, 27, 131–142.
20. Tiwari, P., Deo, M. Compositional and kinetic analysis of oil shale pyrolysis using TGA–MS. Fuel, 2012, 94, 333–341.
http://dx.doi.org/10.1016/j.fuel.2011.09.018
21. Zanoni, M. A. B., Massard, H., Martins, M. F., Salvador, S. Application of inverse problem and thermogravimetry to determine the kinetics of oil shale pyrolysis. High Temp.-High Press., 2012, 41(3), 197–213.
22. Al-Harahsheh, M., Al-Ayed, O., Robinson, J., Kingman, S., Al-Harahsheh, A., Tarawneh, K., Saeid, A., Barranco, R. Effect of demineralization and heating rate on the pyrolysis kinetics of Jordanian oil shales. Fuel Process. Technol., 2011, 92(9), 1805–1811.
http://dx.doi.org/10.1016/j.fuproc.2011.04.037
23. Kök, M. V., Iscan, A. G. Oil shale kinetics by differential methods. J. Therm. Anal. Calorim., 2007, 88(3), 657–661.
http://dx.doi.org/10.1007/s10973-006-8027-y
24. Wang, C., Zhang, X., Liu, Y., Che, D. Pyrolysis and combustion characteristics of coals in oxyfuel combustion. Appl. Energ., 2012, 97, 264–273.
http://dx.doi.org/10.1016/j.apenergy.2012.02.011
25. Vyazovkin, S., Chrissafis, K., Di Lorenzo, M. L., Koga, N., Pijolat, M., Roduit, B., Sbirrazzuoli, N., Suñol, J. J. ICTAC Kinetics Committee recommendations for collecting experimental thermal analysis data for kinetic computations. Thermochim. Acta, 2014, 590, 1–23.
http://dx.doi.org/10.1016/j.tca.2014.05.036
26. Jacobs, P. W. M., Tompkins, F. C. Classification and theory of solid reactions. In: Chemistry of the Solid State (Garner, W. E., ed.). Butterworths, London, 1955, 184–212.
27. Coats, A. W., Redfern, J. P. Kinetic parameters from thermogravimetric data. Nature, 1964, 201, 68–69.
http://dx.doi.org/10.1038/201068a0
28. Cook, E. W. Oil-shale technology in the USA. Fuel, 1974, 53(3), 146–151.
http://dx.doi.org/10.1016/0016-2361(74)90001-5
29. Qing, W., Baizhong, S., Aijuan, H., Jingru, B., Shaohua, L. Pyrolysis characteristics of Huadian oil shales. Oil Shale, 2007, 24(2) 147–157.
30. Yan, J., Jiang, X., Han, X., Liu, J. A TG-FTIR investigation to the catalytic effect of mineral matrix in oil shale on the pyrolysis and combustion of kerogen. Fuel, 2013, 104, 307–317.
http://dx.doi.org/10.1016/j.fuel.2012.10.024
31. Braun, R. L., Rothman, A. J. Oil-shale pyrolysis: kinetics and mechanism of oil production. Fuel, 1975, 54(2), 129–131.
http://dx.doi.org/10.1016/0016-2361(75)90069-1
32. Knauss, K. G., Copenhaver, S. A., Braun, R. L., Burnham, A. Hydrous pyrolysis of New Albany and Phosphoria shales: production kinetics of carboxylic acids and light hydrocarbons and interactions between the inorganic and organic chemical systems. Org. Geochem., 1997, 27(7–8), 477–496.
http://dx.doi.org/10.1016/S0146-6380(97)00081-8
33. Ots, A. Oil Shale Fuel Combustion. tallinna Raamatutrükikoda, 2006.
34. Schenk, H. J., Dieckmann, V. Prediction of petroleum formation: the influence of laboratory heating rates on kinetic parameters and geological extrapolations. Mar. Petrol. Geol., 2004, 21(1), 79–95.http://dx.doi.org/10.1016/j.marpetgeo.2003.11.004
