微波辐射下神木-府谷烟煤有机质的溶出规律及组成结构

Dissolved Law and Chemical Composition of Organic Matter in Shenmu-Fugu Coal Under Microwave Irradiation

提高煤中有机质的可溶性,从分子水平上了解煤中可溶有机质的组成结构,是实现煤炭资源高效清洁利用的关键性科学问题.本文在微波辐射下对神木-府谷烟煤(SFBC)进行溶剂萃取,考察了微波辐射功率、辐射时间以及溶剂类型对SFBC萃取过程的影响,并利用气相色谱/质谱联用仪(GC/MS)分析了萃取物的组成.结果表明:微波辐射40min时,SFBC的萃取率随微波功率的提高而降低,微波辐射10、20和30min时,SFBC的萃取率随微波功率的提高呈先增加后减小的趋势;SFBC的萃取率与溶剂的介电常数有关,在介电常数较小的四氢呋喃中萃取率最高(5.6%);萃取物主要由脂肪烃和芳烃组成,推测脂肪烃和小分子的芳烃较易从煤的大分子网络中游离出来.

Converting coal to more soluble fraction and understanding the molecular compositions and structures of the soluble organic matter in molecular level is crucially important and essential for efficient and clean utilization of coal.Extraction behavior of Shenmu-Fugu bituminous coal（SFBC）in various organic solvents was investigated at microwave powers ranging from 150 Wto 240 Wand microwave irradiation time ranging from 10 min to 40 min.The extracts of SFBC obtained at different solvents were analyzed with gas chromatography/mass spectrometry（GC/MS）.The results show that the extract yield（EY）of SFBC remarkably decreased with raising the microwave power when microwave irradiate for 40 min,whereas microwave irradiation for 10,20 and 30min,the EY of SFBC slightly increased and then significantly decreased.The EY of SFBC is largely related to dielectric constant of the solvents.The main group components in the extracts of SFBC are alkyl arenes,alkanes,alkenes,oxygen-containing organic compounds,and sulfur-containing organic compounds,of which alkanes,alkenes and alkyl arenes are predominant,implying that these group components are more easily to release from macromolecular structure of SFBC.