n-Paraffins obtained by extraction and mild stepwise hydrogenation of Wandoan coal

• Published in: Fuel (Guildford) Vol. 65; no. 8; pp. 1073 - 1078
• Main Authors: Dong, Ji-Zhou, Katoh, Takashi, Itoh, Hironori, Ouchi, Koji
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.08.1986; Elsevier
• Subjects: Applied sciences; chemical characterization; coal; Energy; Exact sciences and technology; Fuel processing. Carbochemistry and petrochemistry; Fuels; hydrogenation; Solid fuel processing (coal, coke, brown coal, peat, wood, etc.); chemical characterization; coal; hydrogenation; Carbochemistry; Coal; Chemical structure; Manufacturing; Solvent extraction; Paraffin; Hydrogenation
• ISSN: 0016-2361; 1873-7153
• DOI: 10.1016/0016-2361(86)90170-5

Wandoan Australian coal was separated into three parts by the float and sink method. The light(I) and medium(II) density fractions were extracted both by benzene-ethanol using ultrasonic irradiation and at 200 °C in an autoclave. The residue was hydrogenated in steps to obtain the n-hexane soluble part, raising the reaction temperature from 320 to 390 °C. The n-paraffins were analysed for each extract. Those from ambient extraction showed a bimodal distribution in the C 12-C 31 region with odd carbon numbers predominating in the C 23-C 31 region. In the case of the 200 °C extract a smooth distribution appeared at C 12-C 31. For the first hydrogenation, the paraffins were distributed at C 12-C 32 with a slight predominance of odd-paraffins in the C 23-C 31 region, and only one maximum at C 26. When the temperature was increased from 320 to 390 °C the distribution approached two maxima at C 12 and C 26, with the former increasing in amount with the temperature. At the final stage there is a slight predominance of even paraffins in the region C 14-C 20 which is believed to originate from esters, acids, alcohols etc. It was also found that there was no serious difference between part I and II in the distribution of n-paraffins, but part I yielded greater amounts of saturated hydrocarbons than the corresponding part II.