Нови приступи у проучавању матурационих промена органске супстанце хумусних угљева

Abstract

У овој дисертацији су проучаване матурационе промене органске супстанце хумусних угљева, почев од касне дијагенезе до полуантрацитског степена карбонификације, што одговара опсегу рефлексије витринита (Rr)= 0.4-1.8 %. Сазревање органске супстанце је симулирано пиролизом узорака мрког (Rr = 0.42 %) и каменог угља (Rr = 0.56 %) из Боговинског угљоносног басена. Пиролиза је изведена у затвореном систему, на температурама од 250 и 400 °C ...

This thesis investigates the maturation changes of organic matter in humic coals,starting from the late diagenesis up to the semianthracite stage of carbonification, whichcorresponds to the vitrinite reflectance (Rr) range of 0.4-1.8 %. Organic mattermaturation was simulated by the closed-system pyrolysis at 250 and 400 °C, conductedon a subbituminous (Rr = 0.42 %) and a bituminous coal (Rr = 0.56 %) from theBogovina coal basin.The changes in kerogen and bitumen were analyzed. Vitrinite contentscontinually increase within 0.4-1.8 % Rr range. Sporinite, resinite, suberinite, andalginite are the most reactive liptinite macerals. The most important liquid products oftheir thermolysis are n-alkanes, n-alkylbenzenes, n-alkylthiophenes, andn-alkylbenzo[b]thiophenes. Liptinites substantially degrade at 400 °C (Rr = 1.8 %),producing primarily n-alkanes. Inertinite contents increase up to Rr = 0.8 %, followedby a slight decrease in Rr = 0.8-1.8 % maturation range.The distributions of various compounds in pyrolysis oil indicate a substantialincrease in thermal maturity, particularly at Rr = 1.8 %. The oils obtained at 400 °Cshow the petroleum-type distribution of hydrocarbons. The applicability of maturityparameters was determined in 0.4-1.8 % Rr range. A new maturity parameter, having agood sensitivity in this wide maturity range, is defined based on the distribution ofmethylfluorenes.Coal asphaltenes were investigated by pyrolysis, in the same manner as humiccoals, and by mild oxidation methods. The pyrolysis at 400 °C and the mild oxidation ofasphaltenes increase the maturity level. Hence, the oil obtained at 250 °C most closelyresembles bitumen, particularly in low rank coals. Coal asphaltenes have a greaterhydrocarbon generation potential than coal kerogen.A new series of biomarkers was discovered (C33-C35 31-methylbenzohopanes)and their application in correlation studies was defined.