Comparison of three methods for extracting Liuhuanggou bituminous coal. (15th December 2017)

• Record Type: Journal Article
• Authors: Yu, Xin-Yue; Wei, Xian-Yong; Li, Zhan-Ku; Chen, Yi; Zong, Zhi-Min; Ma, Feng-Yun; Liu, Jing-Mei
• Is Part Of: Fuel. Volume 210(2017)
• Page Start: 290
• Page End: 297
• Publication Date: 2017-12-15
• Subjects: Microwave-assisted extraction -- Ultrasonic-assisted extraction -- Ultrasonic/microwave-assisted extraction -- Sequential extraction; Fuel -- Periodicals; Coal -- Periodicals; Coal; Fuel; Periodicals; 662.6
• DOI: 10.1016/j.fuel.2017.08.071
• Languages: English
• ISSNs: 0016-2361

Abstract

Highlights: Each aromatic cluster in LBC contains 2 or 3 rings on average. A number of highly condensed arenes (HCAs) were detected in the extracts from LBC. MAE more effectively facilitates extracting HCAs from LBC than UMAE. More heteroatom-containing species were extracted via MAE and UMAE than via UAE. Associated species could be dissociated by UMAE. Abstract: Microwave-assisted extraction (MAE), ultrasonic-assisted extraction (UAE), and ultrasonic/microwave-assisted extraction (UMAE) were separately conducted on the extraction of Liuhuanggou bituminous coal (LBC) sequentially using petroleum ether, carbon disulfide (CDS), methanol, and isometric CDS/acetone mixture as solvents to afford extracts 1–4 (E1 -E4 ) from MAE (EM1 -EM4 ), UAE (EU1 -EU4 ), and UMAE (EUM1 -EUM4 ). The highest total extract yield of 10.6 wt% was obtained by UMAE, while MAE is the most effective for extracting highly condensed arenes from LBC. The carbon types in LBC mainly consist of aliphatic (22.2%) and aromatic (73.7%) carbons. Each aromatic cluster of LBC contains 2 or 3 aromatic rings on average. The molecular masses of EU3, EU4, EM3, and EM4 range from 200 to 1500 u, while those in EUM3 and EUM4 distribute from 100 to 900 u . EUM2 is a promising feedstock to produce advanced aromatic polymers and EUM3 could be converted to clean light oil by catalytic hydroconversion after removing heteroatom-containing species (HACSs). MAE and UMAE are ideal tools to obtain value-added chemicals for their high selectivity of extracting HACSs.