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Xilihaote lignite (XL) and Geting bituminous coal (GBC) were extracted using isometric carbon disulfide/acetone binary solvent at 45°C under microwave irradiation. The raw coals and residues were analyzed with a Fourier transform infrared spectrometer and the extracts with a gas chromatograph/mass spectrometer. The results show that the extract yield of GBC is much higher than that of XL lignite and the molecular composition of the extract from XL is significantly different of that from GBC. [ABSTRACT FROM PUBLISHER]

A raw bio-oil (RBO) from pyrolysis of rice husk was upgraded by catalytic esterification with methanol over an acidic resin. Both RBO and the upgraded bio-oil (UBO) were analyzed with a Fourier transform infrared spectrometer, pH meter, and an elemental analyzer. They were extracted sequentially withn-hexane, CCl4, CS2, benzene, and CH2Cl2. All of the extracts were analyzed with gas chromatography/mass spectrometer. The results showed that the carboxylic acids (CA) in the RBO were converted to their corresponding methyl esters (MEs), leading to a significant increase in pH value from 2.8 (RBO) to 5.3 (UBO). The total extract yield of UBO is much higher than that of RBO. In total, 20 CAs and 19 MEs were identified. The CAs include two alkenoic acids, a cycloalkanecarboxylic acid, a hydroxyalkanoic acid, a hydroxyalkenoic acid, an oxyalkanoic acid, a methoxyoxyalkanoic acid, an alkanedioic acid, an oxyalkanedioic acid, an aminoalkanoic acid, two furoic acids, three substituted benzoic acids, and five substituted phenylalkanoic acids. [ABSTRACT FROM PUBLISHER]

Geting bituminous coal was sequentially extracted with petroleum ether, carbon disulfide, methanol, acetone, and isometric carbon disulfide/acetone mixed solvent at room temperature, affording extracts 1 to 5 (E1to E5). In total, 77 organooxygen compounds (OOCs) were identified from E3by gas chromatography/mass spectrometry analysis. The OOCs include 4 alkanols, 8 arenols, 5 ethers, 5 aldehydes, 14 non-nitrogen ketones, 19 nitrogen-containing ketones, 11 alkanoic acids, and 11 esters. This investigation provides an effective approach to the enrichment of OOCs in coals, favoring understanding of the diversity of the organooxygen compounds. [ABSTRACT FROM AUTHOR]