Cathodic dissolution behavior of an aluminum wire electrode in solutions containing borate and sulfate ions

2004 ◽  
Vol 567 (1) ◽  
pp. 1-7 ◽  
Author(s):  
Kazuhisa Azumi ◽  
Tomohiro Ueno ◽  
Masahiro Seo
Keyword(s):  
Dissolution Behavior ◽  
Wire Electrode ◽  
Aluminum Wire ◽  
Sulfate Ions

scholarly journals Forming sulfate- and REE-rich fluids in the presence of quartz

Geology ◽  
2019 ◽  
Vol 48 (2) ◽  
pp. 145-148 ◽  
Author(s):  
Hao Cui ◽  
Richen Zhong ◽  
Yuling Xie ◽  
Xueyin Yuan ◽  
Weihua Liu ◽  
...  
Keyword(s):  
Earth Element ◽  
Hydrothermal Systems ◽  
Chloride Ions ◽  
Dissolution Behavior ◽  
Sulfate Ions ◽  
Retrograde Solubility ◽  
Sulfate Salts ◽  
Water Saturated ◽  
Sulfate Melt ◽  
Sulfate Complexes

Abstract The presence of sulfate-rich fluids in natural magmatic hydrothermal systems and some carbonatite-related rare earth element (REE) deposits is paradoxical, because sulfate salts are known for their retrograde solubility, implying that they should be insoluble in high-temperature geofluids. Here, we show that the presence of quartz can significantly change the dissolution behavior of Na2SO4, leading to the formation of extremely sulfate-rich fluids (at least 42.8 wt% Na2SO4) at temperatures >∼330 °C. The elevated Na2SO4 solubility results from prograde dissolution of immiscible sulfate melt, the water-saturated solidus of which decreases from ≥∼450 °C in the binary Na2SO4-H2O system to ∼270 °C in the presence of silica. This implies that sulfate-rich fluids should be common in quartz-saturated crustal environments. Furthermore, we found that the sulfate-rich fluid is a highly effective medium for Nd mobilization. Thermodynamic modeling predicts that sulfate ions are more effective in complexing REE(III) than chloride ions. This reinforces the idea that REEs can be transported as sulfate complexes in sulfate-rich fluids, providing an alternative to the current REE transport paradigm, wherein chloride complexing accounts for REE solubility in ore fluids.

Voltammetric, potentiometric and amperometric studies with a rotated aluminum wire electrode

1960 ◽  
Vol 22 ◽  
pp. 351-363 ◽  
Author(s):  
I.M. Kolthoff ◽  
E.J. Meehan ◽  
C.J. Sambucetti
Keyword(s):  
Wire Electrode ◽  
Aluminum Wire

Study of cathodic dissolution of an aluminum wire electrode using ac resistometry

2003 ◽  
Vol 540 ◽  
pp. 97-104 ◽  
Author(s):  
Tomohiro Ueno ◽  
Kazuhisa Azumi ◽  
Masahiro Seo
Keyword(s):  
Wire Electrode ◽  
Aluminum Wire

The Effects of Carbonate-Bicarbonate Concentration on Empirical Corrosion Diagram of Mild Steel as a Material of Geological Disposal Package for High Level Nuclear Wastes

1996 ◽  
Vol 451 ◽  
Author(s):  
Guen Nakayama ◽  
Yuichi Fukaya ◽  
Masatsune Akashi
Keyword(s):  
Mild Steel ◽  
Human Life ◽  
General Corrosion ◽  
Nuclear Wastes ◽  
Bicarbonate Concentration ◽  
Sulfate Ions ◽  
Geological Disposal ◽  
Groundwater Environment ◽  
High Level ◽  
Corrosion Diagram

ABSTRACTIn the scheme for geological disposal of high level radioactive nuclear wastes, the burial pit is to be isolated from the sphere of human life by a multiple-barrier system, which consists of an artificial barrier, composed of a canister, an overpack and a bentonite cushioning layer, and a natural barrier, which is essentially the bedrock. As the greatest as well as essentially the sole detriment to its integrity would be corrosion by groundwater. The groundwater comes to it seeping through the bentonite zone, thereby attaining conceivably the pH of transition from general corrosion to passivity, pHd, the behaviors of mild steel in such a groundwater environment have been examined. It has been shown that the pHd is lowered (enlargement of the passivity domain) with rising temperature and carbonate-bicarbonate concentration, while it is raised (enlargement of the general corrosion region) with increasing concentrations of chloride and sulfate ions.

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