In the pyrolytic decomposition of kerogen, a macromolecular cross-linked material of oil shale, the formation of thermobitumen is often considered an important intermediate step in pyrolysis modelling. The authors’ literature review indicated that information regarding the yield of thermobitumen from Kukersite oil shale was somewhat contradictory, and data on physical-thermodynamic properties, which is to be used in engineering calculations, was limited. Therefore the present work provides further information on thermobitumen yield levels and properties, along with empirical correlations, which serve to link together pyrolysis temperature, time, and/or selected properties (molecular weight, H/C, density, refractive index, and heat capacity). No information can be found on the last three properties for thermobitumens, derived from either Kukersite oil shale or other oil shale. The paper contributes to the topic by presenting information under conditions in which volatile pyrolytic products (oil and water) were removed from a pyrolysis system by an inert gas flow. So far, the formation of thermobitumen in Kukersite oil shale pyrolysis has been studied in either closed or open systems with no inert gas flow. To further generalise the results, the article also presents some comparisons with Green River formation oil shale thermobitumens, which were produced under similar conditions.
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