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To investigate the structural features and provide an alternative method for high value-added utilization of coal, Lingwu coal was first extracted with organic solvent at room temperature. Then its extraction residue was oxidized in aqueous sodium hypochlorite(ASHC) under mild conditions. The effects of oxidation conditions, such as temperature, reaction time, the ratio of Lingwu coal extraction residue(LCER, g) to ASHC(m L) and p H value, on the product distributions and compositions were investigated. The results of gas chromatography/mass spectrometry(GC/MS) suggested that 53 kinds of methyl esterified products were detected in total, and benzene carboxylic acids were the main oxidation products, while chloro-substituted benzene carboxylic acids were the main by-products. Higher yield and fewer kinds of organic acids could be obtained at lower p H value, especially for the main objective product, benzene carboxylic acids. 相似文献
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Comparative study on the pyrolysis behaviors of corn stalk and pine sawdust using TG-MS 总被引：1，自引：0，他引：1
The pyrolysis behaviors of corn stalk（CS） and pine sawdust（PS） were investigated with thermogravimetry-mass spectroscopy（TG-MS）.The peak temperature of PS was higher and the main decomposition region shifted to higher temperature compared with CS,which implied that the hemicellulose and cellulose of PS were more thermally stable than those of CS.However,the hemicellulose and cellulose of PS were more easily decomposed into gaseous products than those of CS during pyrolysis.The pyrolysis process of biomass can be described by a two-step independent first-order kinetic model.This fundamental study provides a basic insight into the biomass pyrolysis,which is beneficial for understanding the pyrolysis mechanism of biomass and developing an advanced thermal process for effective utilization of biomass. 相似文献
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High-temperature coal tar was extracted with petroleum ether(PE) under ultrasonic irradiation and the extracts were analyzed with gas chromatograph/mass spectrometer.The acearylene fractions including acenaphthylene,aceanthrylene and cyclopentapyrene were enriched together and named E,which was then transferred to a cartridge in Isolera-One flash chromatography.Three groups of compounds were eluted out with ethyl acetate/PE mixed solvent(volume ratio 1:9) and named E 1,E 2 and E 3 according to their main components.Acenaphthylene accounted for 78.2% in E 1,aceanthrylene 71.6% in E 2 and cyclopentapyrene 75.9% in E 3,respectively.The three groups of acearylenes were purified by Sephadex LH-20 column chromatography with ethanol/cyclohexane mixed solvent(volume ratio 1:4),and then confirmed with nuclear magnetic resonance spectrometer.This method indicates that flash chromatography has a good effect on separating the compounds with a similar structure after extraction under ultrasonic irradiation. 相似文献
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