Visual and in situ Raman spectroscopic observations of the liquid-liquid immiscibility in aqueous uranyl sulfate solutions at temperatures up to 420 degrees C

doi:10.1016/j.supflu.2016.03.005

CORC > 深海科学与工程研究所 > 中国科学院深海科学与工程研究所 > 深海科学研究部 > 深海极端环境模拟研究实验室

	Visual and in situ Raman spectroscopic observations of the liquid-liquid immiscibility in aqueous uranyl sulfate solutions at temperatures up to 420 degrees C
	Cai, Shenyang 1; Wang, Xiaolin 1,2; Wan, Ye 1; Hu, Wenxuan 1,2; Chou, I-Ming3 ; Lin, Nan 1; Zhu, Qiang 1; Li, Zhen 4
刊名	JOURNAL OF SUPERCRITICAL FLUIDS
	2016-06-01
卷号	112 页码:95-102
关键词	Uo2so4-h2o Liquid-liquid Immiscibility Raman Spectroscopy Ion associatIon
DOI	10.1016/j.supflu.2016.03.005
文献子类	Article
英文摘要	The phase behaviors of aqueous UO2SO4 solutions were investigated in situ with a microscope and a Raman spectrometer at temperatures from 25 to 420 degrees C. Results show that aqueous UO2SO4 solution separated into UO2SO4-rich (U-rich) and UO2SO4-poor (U-poor) liquid phases coexisted with a vapor poor, phase at >= 285.8 +/- 0.5 degrees C. Both visual and Raman spectroscopic investigations suggest that a reversible strong UO22+-SO42- association was responsible for the liquid-liquid immiscibility in aqueous UO2SO4 solutions. Main evidences were summarized as: (1) the liquid-liquid phase separation temperature decreases with increasing UO2SO4 concentration up to 0.54 mol/kg, and then increased at greater concentrations, characterizing a lower critical solution temperature (LCST) at 285.8 degrees C +/- 0.5 degrees C. LCST is commonly accepted as a diagnostic feature of polymer solutions; (2) analyses of the shapes of the Raman spectra of nu(1) (UO22+) and nu(1) (SO42-) bands show that the UO22+-SO42- association becomes stronger at elevated temperatures, especially in the immiscible U-rich, phase; and (3) with increasing temperature, the U-rich phase becomes more concentrated, whereas the U-poor phase becomes more dilute, indicating that the hydration of UO22+ and SO42- cannot be maintained in the U-rich phase. Destruction of the hydration spheres of UO22+ and SO42- further favors the ion association in the U-rich, phase. These results are important for describing similar sulfate solutions at elevated temperatures, especially under supercritical conditions. (C) 2016 Elsevier B.V. All rights reserved.
WOS关键词	CONTACT ION-PAIRS ; MAGNESIUM-SULFATE ; AB-INITIO ; HYDROTHERMAL CONDITIONS ; DIOXOURANIUM(VI) ION ; SYSTEMS UO3-SO3-H2O ; SUPERCRITICAL WATER ; SALT PRECIPITATION ; COMPLEX-FORMATION ; FLUID INCLUSIONS
语种	英语
WOS记录号	WOS:000374078100013
内容类型	期刊论文
版本	预印本
源URL	[http://ir.idsse.ac.cn/handle/183446/1565]
专题	深海科学研究部_深海极端环境模拟研究实验室
通讯作者	Wang, Xiaolin
作者单位	1.Nanjing Univ, Sch Earth Sci & Engn, State Key Lab Mineral Deposits Res, Nanjing 210023, Jiangsu, Peoples R China 2.Nanjing Univ, Inst Energy Sci, Nanjing 210023, Jiangsu, Peoples R China 3.Chinese Acad Sci, Sanya Inst Deep Sea Sci & Engn, Lab Expt Study Deep Sea Extreme Condit, Sanya 572000, Hainan, Peoples R China 4.Curtin Univ, Dept Appl Geol, Perth, WA 6845, Australia
推荐引用方式 GB/T 7714	Cai, Shenyang,Wang, Xiaolin,Wan, Ye,et al. Visual and in situ Raman spectroscopic observations of the liquid-liquid immiscibility in aqueous uranyl sulfate solutions at temperatures up to 420 degrees C[J]. JOURNAL OF SUPERCRITICAL FLUIDS,2016,112:95-102.
APA	Cai, Shenyang.,Wang, Xiaolin.,Wan, Ye.,Hu, Wenxuan.,Chou, I-Ming.,...&Li, Zhen.(2016).Visual and in situ Raman spectroscopic observations of the liquid-liquid immiscibility in aqueous uranyl sulfate solutions at temperatures up to 420 degrees C.JOURNAL OF SUPERCRITICAL FLUIDS,112,95-102.
MLA	Cai, Shenyang,et al."Visual and in situ Raman spectroscopic observations of the liquid-liquid immiscibility in aqueous uranyl sulfate solutions at temperatures up to 420 degrees C".JOURNAL OF SUPERCRITICAL FLUIDS 112(2016):95-102.