The structure of kukersite organic matter has been a matter of scientific investigation and disputes over a hundred years. When considering the publications on the subject the authors of the current article concluded that the structure of kukersite is well described by a model proposed independently by Ülo Lille and Peter Blokker at the beginning of this millennium. This model characterizes the behaviour of kukersite in thermal processing and predicts the behaviour of oil shale kerogen in oxidation and other chemical transformations. The structural model may serve as a basis for new technologies for oil shale processing in order to get valuable chemicals directly from it.
1. Oja, V., Suuberg, E. M. Oil shale processing, chemistry and technology. In: Encyclopedia of Sustainability Science and Technology (Meyers, R. A., ed.), Springer Science+Business Media, 2017, 1–34.
https://doi.org/10.1007/978-1-4939-2493-6_102-3
2. Vandenbroucke, M., Largeau, C. Kerogen origin, evolution and structure. Org. Geochem., 2007, 38(5), 719–833.
https://doi.org/10.1016/j.orggeochem.2007.01.001
3. Zalessky, M. On marine sapropelite of Silurian age formed by blue green alga. Bulletin de l’Académie des Sciences de Russie, VI Série, 1917, 11(1), 3–18 (in Russian).
4. Zalessky, M. Sur le sapropélite marin de l’âge silurien formé par une algue cyanophycée. Yearbook of Russ. Palaeont. Soc. Petrograd, 1917, I, 25–42 (in Russian).
5. Fokin, L. F. The structure and products of decomposition of Esthonian bituminous rocks. Gorny Zhurnal, 1913, II, 117 (in Russian).
6. Foster, C. B., Reed, J. D., Wicander, R. Gloeocapsamorpha prisca Zalessky, 1917: A new study. Part 1: taxonomy, geochemistry and paleoecology. Geobios,1989, 22(6), 735–759.
https://doi.org/10.1016/S0016-6995(89)80070-1
7. Kogerman, P. The chemical composition of the Esthonian M.-Ordovician oil-bearing mineral „kukersite“. Acta et Commentationes Universitatis Dorpatensis, 1922, AIII(6), 3–25.
8. Kogerman, P. The chemical nature of Estonian oil-shale. The origin of oil-shales. Sitzungberichte der Naturforscher-Gesellschaft bei der Universität Tartu, 1927, XXXIV(2), 166–182.
9. Kogerman, P. Oxidation – a method to study a chemical nature of shales. Izvestiya AN ESSR, 1952, 1(1), 108–116 (in Russian).
https://doi.org/10.3176/toimetised.1952.1.03
10. Fomina, A. S., Pobul, L. Y. Oxidative destruction of kukersite kerogen. I. Izvestiya AN ESSR, 1953, 11(1), 91–102 (in Russian).
https://doi.org/10.3176/toimetised.1953.1.04
11. Fomina, A. S., Pobul, L. Y. Oxidative destruction of kukersite kerogen. II. Izvestiya AN ESSR, 1953, 11(4), 551–562 (in Russian).
https://doi.org/10.3176/toimetised.1953.4.05
12. Fomina, A. S., Pobul, L. Y. Oxidative destruction of kukersite kerogen. III. Izvestiya AN ESSR, 1955, 13(1), 48–56 (in Russian).
https://doi.org/10.3176/toimetised.1955.1.04
13. Fomina, A. S. Kukersite, its chemical nature and origin. Izvestiya AN ESSR, 1958, 7(2), 91–104 (in Russian).
14. Pobul, L. J., Männik, A. O., Fomina, A. S., Ikonopisceva, O. A., Bondar, E. B. Belonging of di- and tricarboxylic acids to the native structure of kukersite kerogen. Khim. Tverd. Topliva, 1974, 3, 115–122.
15. Fomina, A. S. On the genesis of Baltic kukersite oil shales. In: Genezis Tverdykh Goryuchikh Iskopaemykh (Karavaev, N. M., Titov, N. G., eds,). Academy of Sciences of the USSR, Moscow, 1959, 77–91 (in Russian).
16. Klesment, I., Urov, K., Eisen, O. Some regularities in the composition of semicoking oil of Estonian oil shale kukersite. Eesti NSV Teaduste Akadeemia Toimetised. Keemia. Geoloogia, 1973, 22(4), 306–311 (in Russian).
https://doi.org/10.3176/chem.geol.1973.4.05
17. Klesment, I., Rikken, J., Urov, K., Viires, A., Eisen, O. Composition and formation of 4-alkylresorcinols of semicarbonization tar of oil shale kukersite. Eesti NSV Teaduste Akadeemia Toimetised. Keemia. Geoloogia, 1974, 23(3), 267–268.
https://doi.org/10.3176/chem.geol.1974.3.14
18. Klesment, I. On the role of fatty acids in the genesis of Estonian combustible oil shale-kukersite. Khim. Tverd. Topliva, 1973, 2, 33–39.
19. Klesment, I. Aliphatic carbon chains of oil shale kerogen. Structure and genesis. Eesti NSV Teaduste Akadeemia Toimetised. Keemia. Geoloogia, 1975, 24(2), 123–129 (in Russian).
https://doi.org/10.3176/chem.geol.1975.2.03
20. Klesment, I., Nappa, L. Investigation of the structure of Estonian oil shale kukersite by conversion in aqueous suspension. Fuel, 1980, 59(2), 117–122.
https://doi.org/10.1016/0016-2361(80)90052-6
21. Arro, J., Klesment, I. Heavy semicoking oil of kukersite shale as a key to a better understanding of the kerogen structure. Oil Shale, 1984, 1(3), 285–290 (in Russian).
https://doi.org/10.3176/oil.1984.3.08
22. Raudsepp, H. T. On the new method of research of chemical structure of combustible fossils and on the chemical structure of the Estonian oil shale –kukersite. Izvestiya AN SSSR, Otd. Tekhn. Nayk, 1954, 3, 130–135 (in Russian).
23. Raudsepp, H. Oil shale phenols. In: Goryuchie Slantsy. Khimiya i Tekhnologiya. Academy of Sciences of Estonian SSR, Tallinn, 1956, 107–116 (in Russian).
24. Aarna, A, J., Lippmaa, E. T. On the structure of the Baltic oil shale kerogen. Transact. Tallinn Polytechnic Institute, Ser. A, 1955, 63, 3–50 (in Russian).
25. Lippmaa, E., Alla, M., Kundla, E. High resolution 13C NMR of organic solids, magic angle spinning, anisotropic interactions and solid state effects. The 18th ENC Conference, Asilomar, California, April 11–15, 1977.
26. Bajc, S., Amblès, A., Largeau, C., Derenne, S., Vitorović, D. Precursor bio-structures in kerogen matrix revealed by oxidative degradation: oxidation of kerogen from Estonian kukersite. Org. Geochem., 2001, 32(6), 773–784.
https://doi.org/10.1016/S0146-6380(01)00042-0
27. Lille, Ü., Bitter, L., Kundel, H., Murd, A., Peinar, U. Die Gewinnung von Alkylresorcinen aus wasserlöslichen Phenolen des Brennschieferols. Eesti NSV Teaduste Akadeemia Toimetised. Keemia. Geoloogia, 1969, 18(4), 359–364 (in Russian).
https://doi.org/10.3176/chem.geol.1969.4.09
28. Lille, Ü. E. Composition and properties of shale phenols. United Nations Symposium on the Development and Utilization of Oil Shale Resources, 28 August – 4 September 1968, Tallinn, Sec. 3.
29. Lille, Ü. E. On the genesis of phenols in thermal degradation of kukersite kerogen. Khim. Tverd. Topliva, 1969, No. 4, 107–110 (in Russian).
30. Lille, Ü. E., Bitter, L. A., Kundel, H. A. On the similarity of structure of shale oil alkylresorcinols and natural alkylresorcinols. Khim. Tverd. Topliva, 1972, No. 6, 137–138 (in Russian).
31. Kozubek, A., Tyman, J. H. P. Resorcinolic lipids, the natural non-isoprenoid phenolic amphiphiles and their biological activity. Chem. Rev., 1999, 99(1), 1–26.
https://doi.org/10.1021/cr970464o
32. Eglinton, G., Calvin, M. Chemical fossils. Sci. Am., 1967, 216(1), 32–43.
https://doi.org/10.1038/scientificamerican0167-32
33. Hutton, А. C. Organic petrography of oil shales. In: Composition, Geochemistry and Conversion of Oil Shales (Snape, C. E., ed.). Kluver Academic Publishers, Dordrecht, Boston, London, 1995, 17–33.
https://doi.org/10.1007/978-94-011-0317-6_2
34. Derenne, S., Largeau, C., Landais, P., Rochdi, A. Spectroscopic features of Gloeocapsomorpha prisca colonies and of interstitial matrix in kukersite as revealed by transmissioon micro-FT-i.r.: location of phenolic moieties. Fuel, 1994, 73(4), 626–628.
https://doi.org/10.1016/0016-2361(94)90049-3
35. Abbott, G. D., Ewbank, G., Edwars, D., Wang, G. Molecular characterization of some enigmatic Lower Devonian fossils. Geochim. Cosmochim. Acta, 1998, 62, 1407–1418.
https://doi.org/10.1016/S0016-7037(98)00078-7
36. Lille, Ü. On the origin of 5-alkyl-1,3-benzenediols in the retort oil of Estonian kukersite. Oil Shale, 1999, 16(3), 231–237.
https://doi.org/10.3176/oil.1999.3.04
37. Derenne, S., Largeau, C., Casadevall, E., Sinninghe Damsté, J. S., Tegelaar, E. W., de Leeuw, J. W. Characterization of Estonian Kukersite by spectroscopy and pyrolysis: Evidence for abundant alkyl phenolic moieties in an Ordovician, marine, type II/I kerogen, Org. Geochem., 1990, 16(4–6), 873–888.
https://doi.org/10.1016/0146-6380(90)90124-I
38. Hoffmann, C. F., Foster, C. B., Powell, T. G., Summons, R. E. Hydrocarbon biomarkers from Ordovician sediments and the fossil alga Gloeocapsomorpha prisca Zalessky 1917. Geochim. Cosmochim. Acta, 1987, 51(10), 2681–2697.
https://doi.org/10.1016/0016-7037(87)90149-9
39. Reed, J. D., Illich, H. A., Horsfield, B. Biochemical evolutionary significance of Ordovician oils and their sources. Org. Geochem., 1986, 10(1–3), 347–358.
https://doi.org/10.1016/0146-6380(86)90035-5
40. Lille, Ü., Heinmaa, I., Pehk, T. Molecular model of Estonian kukersite kerogen evaluated by 13C MAS NMR spectra. Fuel, 2003, 82(7), 799–804.
https://doi.org/10.1016/S0016-2361(02)00358-7
41. Lille, Ü. Current knowledge on the origin and structure of Estonian kukersite kerogen. Oil Shale, 2003, 20(3), 253–263.
https://doi.org/10.3176/oil.2003.3.03
42. Blokker, P., Van Bergen, P., Pancost, R., Collinson, M. E., De Leeuw, J. W., Sinninghe Damste, J. S. The chemical structure of Gloeocapsomorpha prisca microfossils: implications for their origin. Geochim. Cosmochim. Acta, 2001, 65(6), 885–900.
https://doi.org/10.1016/S0016-7037(00)00582-2
43. Kaldas, K., Preegel, G., Muldma, K., Lopp, M. Wet air oxidation of oil shales: Kerogen dissolution and dicarboxylic acid formation. ACS Omega, 2020, 5(35), 22021–22030.
https://doi.org/10.1021/acsomega.0c01466
44. Kaldas, K., Niidu, A., Preegel, G., Uustalu, J. M., Muldma, K., Lopp, M. Aspects of kerogen oxidative dissolution in subcritical water using oxygen from air. Oil Shale, 2021, 38(3), 199–214.
https://doi.org/10.3176/oil.2021.3.02
45. Mets, B., Uustalu, J. M., Lopp, M., Kaldas, K. Oxidation of kukersite – a two-step model for assessing the potential of shale-derived chemicals by advanced oxidation process (under publication).
