Intrinsic sodium occurrence in Zhundong coal: Experimental observations and molecular modeling

doi:10.1016/j.fuel.2021.121491

CORC > 力学研究所 > 中国科学院力学研究所 > 高温气体动力学国家重点实验室

	Intrinsic sodium occurrence in Zhundong coal: Experimental observations and molecular modeling
	Sun C(孙岑)1,2; Wei XL(魏小林)1,2; Kang RN(康润宁)1,2; Bin F(宾峰)1,2; Li S(李森)2
刊名	FUEL
	2021-12-01
卷号	305 页码:12
关键词	Alkali metal occurrence model Zhundong coal Molecular model DFT NMR
ISSN号	0016-2361
DOI	10.1016/j.fuel.2021.121491
通讯作者	Wei, Xiaolin(xlwei@imech.ac.cn)
英文摘要	Detailed intrinsic sodium occurrence for future research on migration, release, and catalyst effect behavior of sodium is necessary. Complementary characterizations, such as C-13 CP/MAS NMR, FT-IR, Na-23 CP/MAS NMR, XPS, elemental composition analysis, and sequential extraction experiments, were employed to elucidate the actual compound form of sodium as well as Zhundong coal's structural features. Thus, a molecular occurrence model of sodium in Zhundong coal was constructed based on its structural characteristics via computational chemistry. The occurrence model of alkali metals in Zhundong coal, including their compound form, relative content, and distribution properties, was investigated at the microstructural level. Preliminary results show that the amorphous cell formula of Zhundong coal is (C2080H980O380N30S10Na) n. Organic oxygen in Zhundong coal was 67.7% hydroxyl (ethoxy), 15.5% carbonyl, and the remaining 16.8% was attributed to carboxyl. Combined with the Na-23 CP/MAS NMR and sequential extraction experiment, organic sodium accounts for 18.01% of the total. Most inorganic sodium (81.99%) is present as hydrated sodium ion (75.08%), while a small part is present as NaCl crystal phase (3.34%) insoluble-sodium account for 3.57%. Calculated C-13 NMR, FT-IR, and Na-23 NMR spectra of the proposed model agree well with the experimental spectra suggesting that the molecular occurrence model of sodium in Zhundong coal is a particularly convincing model at the approximate condition of statistical average. The highest negative electrostatic potential area is near the carboxyl group and may be attributed to organic sodium absorption sites; the hydroxy or phenoxy group nearby may form additional coordination bonds to sodium, indicating the reflection of the complexity of the Na chemical environment as concluded from Na-23 CP/MAS NMR.
分类号	一类
资助项目	Natural Science Foundation of China[51736010]
WOS关键词	SOLID-STATE C-13 ; DENSITY FUNCTIONALS ; PYROLYSIS ; BEHAVIOR ; THERMOCHEMISTRY ; ALKALI ; SCALE
WOS研究方向	Energy & Fuels ; Engineering
语种	英语
WOS记录号	WOS:000701850600001
资助机构	Natural Science Foundation of China
其他责任者	Wei, Xiaolin
内容类型	期刊论文
源URL	[http://dspace.imech.ac.cn/handle/311007/87480]
专题	力学研究所_高温气体动力学国家重点实验室
作者单位	1.Univ Chinese Acad Sci, Sch Engn Sci, Beijing 100049, Peoples R China 2.Chinese Acad Sci, Inst Mech, State Key Lab High Temp Gas Kinet, Beijing 100190, Peoples R China;
推荐引用方式 GB/T 7714	Sun C,Wei XL,Kang RN,et al. Intrinsic sodium occurrence in Zhundong coal: Experimental observations and molecular modeling[J]. FUEL,2021,305:12.
APA	孙岑,魏小林,康润宁,宾峰,&李森.(2021).Intrinsic sodium occurrence in Zhundong coal: Experimental observations and molecular modeling.FUEL,305,12.
MLA	孙岑,et al."Intrinsic sodium occurrence in Zhundong coal: Experimental observations and molecular modeling".FUEL 305(2021):12.