No abstract

Organic geochemical studies on brown coal (lignite) located in Inul area were carried out, an area that is located in Sangatta coal mines, East Borneo, which is a part of the Balikpapan formation, aged as old as Middle Miocene to Late Miocene. Aliphatic hydrocarbon biomarker compounds which were identified by using the GC-MS analysis showed a presence of n-alkane (n-C12-n-C36) with bimodal distribution, which described the sources of organic compounds that originated from two different sources. These sources of organic compounds are phytoplankton, zooplankton and higher plants terrestrial. The Pr/Ph ratio of 1.3, the dominance of C31-homohopane and a high ratio of Tm/Ts indicated that the process of peat depositions took place in an oxic environment.  The existence of hopanoid contents showed that there were dominant activities of microbes and biolipids organic compounds such as bb-hopane and hop-17(21)-ene inside the samples of olean-12-ene and a-cadinene, which inidicated that they are organic compounds that came from higher plants such as Angiosperm and immature coals. The existence of 24-ethylcholestene and 5b-cholest-24-ene found in the coal samples, which are categorised as steranes, also indicated a low level of carbonization from the coal itself.

The Middle to Late Miocene brown coal extracted from Inul area, Sangatta coal mines, East Kalimantan, was studied to recognize the distribution of ketone and acid biomarkers. Samples were extracted using soxhlet method and separated by column chromatography and thin layer chromatography. Acetylation of acid fractions by BF 3 /MeOH produced an ester compound which is an acid derivative. The distributions of fatty acid methyl esters were analyzed with gas chromatography-mass spectrometry (GC-MS). The distributions of ketones included compounds in n-alkan-2-one, amyrin-derived ketone, and friedeline derivatives as well as olean-13(18)-en-3-one with oleanane skeleton. Distributions of fatty acids included compounds in the range from n-methylhexadecanoate (n-C 16) to nmethyltriacontanoate (n-C 30) with dominating compounds from n-methylhexadecanoate (n-C 16) to n-methyldococanoate (n-C 22). The most obvious feature is predominance of compounds with even-over-odd-carbon-atom-number in a molecule, which come from vascular plant fatty acids. The distributions of these biomarker compounds are used as an indicator of higher plant and oxic depositional environment, as well as the involvement of bacteria in diagenesis stage which indicates immature coals.

A section of the Sangatta coalfield in the Balikpapan formation located in Kutai Basin, East Borneo, Indonesia, is the Inul area, located North of Pinang Dome. This section of the coalmine has coals with low calories (ca. 4379 cal/g), which is why they cannot be used optimally yet. The reasons of using low calorie coals are besides from being used as a mixing ingredient for the blending process of high calorie coals, they are also used to diversify the coals through the process of coal liquefaction (coal to liquid). In order for the coal liquefaction to be processed correctly, there needs to be a study on the geochemistry organics through coal biomarker analysis, particularly on the hydrocarbon aromatic fractions, so that the origins of the coal organic compounds could be known. Biomarker analysis on the aromatic hydrocarbon fraction shows the existence of naphthalene compound groups with sesquiterpenoids skeleton, phenanthrene with diterpenoids, sesterpenoids skeleton and triterpenoids aromatic pentacyclic. The existence of cadalene compound, triterpene pentacyclic monoaromatic, -triaromatic, -tetraaromatic, -pentaaromatic and triterpenoid C-ring cleaved hydrocarbon with oleanane, ursane and lupane skeletons indicated that the source of coal organic compounds were derived from b-amyrin which were produced by Angiospermae plants. The coal biomarkers distribution, particularly the high abundance of triterpenoid pentacyclic triaromatic compound, confirmed the low maturity of the coals which is predicted to profit from the process of liquefaction due to the high contents of their aromatic fractions.

The present work aims to study the synthesis of 2-hydroxyethyl esters from castor oil and its lubrication properties, promising as a lubrication bio-additive in low sulfur diesel fuel. This compound has been successfully synthesized from castor oil and ethylene glycol. The oil to ethylene glycol molar ratio was adjusted to 1:10, and the catalyst loading was used at 9% mole oil. Then, the mixture was refluxed for 5 h. The product components were characterized using GC-MS. The standard ASTM method was used to study the kinematic viscosity and lubrication. The product was dominated by 2-hydroxyethyl esters (94.16%), di-ester (1.12%), and cyclic ester (1.92%). The analysis of friction coefficient and wear scar diameter (WSD) using High-Frequency Reciprocating Rig (HFRR) shows the coefficient of friction and WSD of the product better than reference diesel fuel. From the results of this study, the 2-hydroxyethyl ester of castor oil, especially 2-hydroxyethyl ricinoleate, is the main responsible for the lubricating properties. Thus, 2-hydroxyethyl esters of castor oil can be proposed as an alternative bio-additive to improve the lubrication of low-sulfur fossil diesel fuels.