Experimental study of uranyl(VI) chloride complex formation in acidic LiCl aqueous solutions under hydrothermal conditions (T = 21 C?350 °C, Psat) using Raman spectroscopy

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

“…Since samples were heated along a liquid-vapor curve, accurate pressures at the liquid-liquid phase separation points inside FSCCs were unknown and they varied with temperature and UO2SO4 concentration. Different from our previous studies, in order to avoid the reduction of UO2 2+ , the silica tube was not vacuumed before the sealing of the FSCC using hydrogen-oxygen flame [19]. The FSCC has enough mechanical resistance at high temperature (ca.…”

In situ observations of liquid–liquid phase separation in aqueous ZnSO4 solutions at temperatures up to 400 °C: Implications for Zn2+–SO42− association and evolution of submarine hydrothermal fluids

“…980 cm -1 [34]. Both v1(UO2 2+ ) and v1(SO4 2-) bands can serve as indictors to investigate the complexation in the UO2SO4-H2O system because these two Raman bands are sensitive to changes in coordination environment [13][14][17][18][19][20][21][22][23].…”

“…As to the association between UO2 2+ and SO4 2-, Raman spectra of the v1(UO2 2+ ) band has been reported to be an effective indicator [13][14][15][16]; the coordination of UO2 2+ can increase the O=U=O length, causing the v1(UO2 2+ ) band shifts to lower wavenumber [13][14][17][18][19]. In fact, Raman spectra of the v1(SO4 2-) band can also be used to investigate the ion interaction between UO2 2+ and SO4 2-in aqueous solution because the complexation will influence the S-O vibrations of sulfate and cause a shift in the v1(SO4 2-) band, which has been well documented in aqueous MgSO4 solutions [20][21][22][23][24].…”

Uranium mobilization by fluids associated with Ca–Na metasomatism: A P–T–t record of fluid–rock interactions during Pan-African metamorphism (Western Zambian Copperbelt)

“…Thus, a change from oxidizing to reducing redox conditions is essential for U transport and deposition. Field investigations (Kish and Cuney, 1981;Richard et al, 2010) and experimental studies (Dargent et al, 2013a) of U transport under hydrothermal conditions have shown that uranium mineralizations are linked to acidic and chloride-rich brines. Fluid inclusions that are genetically linked to the synmetamorphic uranium mineralization event at 530 Ma exhibit very high chloride concentrations ([Cl] = 12 to 13 mol·kg − 1 solution; Eglinger et al, 2014) and high U contents.…”