Influence of Cathode Potential on Ti Electrodeposition in Molten Fluoride

2016 ◽  
Vol 75 (15) ◽  
pp. 199-206 ◽  
Author(s):  
K. Nishikawa ◽  
S. Humiya ◽  
T. Morishige ◽  
T. Takenaka
Keyword(s):  
Cathode Potential ◽  
Molten Fluoride

scholarly journals Influence of bath composition on Ti metal deposition in molten CaCl2 containing calcium titanate

2020 ◽  
Vol 321 ◽  
pp. 07010
Author(s):  
T. Takenaka ◽  
H. Okada ◽  
R. Shimokawa ◽  
T. Morishige
Keyword(s):  
Calcium Titanate ◽  
Metal Deposition ◽  
Molar Ratio ◽  
Cathode Potential ◽  
Reduction Mechanism ◽  
Titanium Metal ◽  
Bath Composition ◽  
Molten Fluoride ◽  
Ionic States ◽  
Calcium Silicate And Aluminate

The dependence of the cathodic behavior of a Ti ion on the molar ratio of CaO to TiO2 (RCaO/TiO2) was investigated in molten CaCl2 above 1373 K, and the influence of RCaO/TiO2 on Ti metal deposition was discussed. The reduction mechanism changed at RCaO/TiO2 = 1.5; a three-step reduction of Ti was suggested in the melt of RCaO/TiO2 < 1.5, while a two-step reduction seemed to occur above RCaO/TiO2 = 1.5. Titanium metal deposition was also affected by RCaO/TiO2 as well as by the cathode potential, and the suitable RCaO/TiO2 was likely 1.5. Since this value was the same as the suitable value in the molten fluoride system, Ti metal was thought to be obtained only from Ti2O76-. Silicon and Al metal were obtained electrochemically in molten CaCl2 containing calcium silicate and aluminate more easily than Ti metal. The difficulty of the Ti metal deposition is likely to be caused by the so-called shuttle reaction; the shuttle reaction can occur in the Ti metal electrolysis because some ionic states of Ti are stable in the bath. To realize better Ti metal deposition, the control of the shuttle reaction should be important.

NICKELVAC N

Alloy Digest ◽  
1990 ◽  
Vol 39 (12) ◽  
Keyword(s):  
Solid Solution ◽  
Corrosion Resistance ◽  
Heat Treating ◽  
Vacuum Induction Melting ◽  
Induction Melting ◽  
Good Oxidation Resistance ◽  
Temperature Performance ◽  
Molten Fluoride ◽  
Fluoride Salts ◽  
Container Material

Abstract NICKEL VAC N was originally developed as a container material for molten fluoride salts. It is a moderate strength, solid solution strengthened alloy with good oxidation resistance to 1800 F. It has excellent resistance to fluoride salts in the range 1300-1600 F. It is produced by vacuum induction melting followed electroslag remelting. This datasheet provides information on composition, physical properties, elasticity, and tensile properties as well as creep. It also includes information on high temperature performance and corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: Ni-388. Producer or source: Teledyne Allvac.

Unstable Cathode Potential in Alkaline Flow Cells for CO2 Electroreduction Driven by Gas Evolution

2021 ◽  
Author(s):  
Kevin Krause ◽  
ChungHyuk Lee ◽  
Jason K. Lee ◽  
Kieran F. Fahy ◽  
Hisan W. Shafaque ◽  
...  
Keyword(s):  
Gas Evolution ◽  
Cathode Potential ◽  
Flow Cells ◽  
Co2 Electroreduction

Irradiation of thorium-bearing molten fluoride salt in graphite crucibles

2021 ◽  
Vol 375 ◽  
pp. 111094
Author(s):  
P.R. Hania ◽  
D.A. Boomstra ◽  
O. Benes ◽  
P. Soucek ◽  
A.J. de Koning ◽  
...  
Keyword(s):  
Fluoride Salt ◽  
Molten Fluoride

scholarly journals Analysis of Corrosion of Hastelloy-N, Alloy X750, SS316 and SS304 in Molten Salt High-Temperature Environment

Energies ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 543
Author(s):  
Ketan Kumar Sandhi ◽  
Jerzy Szpunar
Keyword(s):  
Weight Loss ◽  
Stainless Steel ◽  
Corrosion Resistance ◽  
Molten Salt ◽  
Corrosion Damage ◽  
Nickel Superalloy ◽  
Triple Junctions ◽  
Salt Corrosion ◽  
Molten Fluoride ◽  
Stainless Steel 316

Nickel superalloy Hastelloy-N, alloy X-750, stainless steel 316 (SS316), and stainless steel 304 (SS304) are among the alloys used in the construction of molten salt reactor (MSR). These alloys were analyzed for their corrosion resistance behavior in molten fluoride salt, a coolant used in MSR reactors with 46.5% LiF+ 11.5% NaF+ 42% KF. The corrosion tests were run at 700 °C for 100 h under the Ar cover gas. After corrosion, significant weight loss was observed in the alloy X750. Weight loss registered in SS316 and SS304 was also high. However, Hastelloy-N gained weight after exposure to molten salt corrosion. This could be attributed to electrochemical plating of corrosion products from other alloys on Hastelloy-N surface. SEM–energy-dispersive X-ray spectroscopy (EDXS) scans of cross-section of alloys revealed maximum corrosion damage to the depth of 250 µm in X750, in contrast to only 20 µm on Hastelloy-N. XPS wide survey scans revealed the presence of Fe, Cr, and Ni elements on the surface of all corroded alloys. In addition, Cr clusters were formed at the triple junctions of grains, as confirmed by SEM–EBSD (Electron Back Scattered Diffraction) analysis. The order of corrosion resistance in FLiNaK environment was X750 < SS316 < SS304 < Hastelloy-N.

Interaction of Pipeline Materials with Molten Fluoride Salts

2007 ◽  
Vol 62 (12) ◽  
pp. 769-774
Author(s):  
Tomáš Šimo ◽  
Oldřich Matal ◽  
Lukáś Nesvadba ◽  
Vladimír Dvořák ◽  
Viktor Kanický ◽  
...  
Keyword(s):  
Inductively Coupled Plasma ◽  
Power Efficiency ◽  
Nuclear Reactor ◽  
Optical Emission ◽  
Theoretical Models ◽  
Emission Spectrometry ◽  
Experimental Investigations ◽  
Salt Melts ◽  
Molten Fluoride ◽  
Fluoride Salts

Molten fluoride salts are very promising carriers for the transport of large amounts of heat for example from a high temperature nuclear reactor to a plant which generates hydrogen by chemical processes or from a nuclear reactor to a heat exchanger being a part of the equipment needed to realize the Brayton cycle with a very high power efficiency. Therefore, in the framework of our project, experimental and theoretical investigations of the interactions of fluoride salts as heat carriers needed as high potential and structural materials for pipelines in order to transport heat at temperatures above 600◦C were started. Experimental investigations of Fe-based and Ni-based materials in molten fluoride salts at high temperatures and with different exposure times were performed. Two components salts (LiF-NaF and NaF-NaBF4) and three components salts (LiF-NaF-ZrF4 and LiF-NaF-RbF) were chosen in the experiments. The salt analysis was focussed on the content of metallic elements before and after the exposure of the samples to the salt melts. It was done by inductively coupled plasma-optical emission spectrometry (ICP-OES) and by titrimetric techniques. The thickness of the material zone affected by the salt melts, characterized by an enriched / reduced content of elements in comparison to the mean original content, and the material attacked zone, characterized by very tiny channels or chains of pores or pits formed preferably at grain boundaries, were the subject of the analysis performed by electron microscopy / microprobe techniques. Theoretical models for the transport of elements in the material samples exposed to salt melts using experimental data were also developed.

A high-performance ethanol–hydrogen peroxide fuel cell

RSC Advances ◽  
2014 ◽  
Vol 4 (110) ◽  
pp. 65031-65034 ◽  
Author(s):  
L. An ◽  
T. S. Zhao ◽  
X. L. Zhou ◽  
L. Wei ◽  
X. H. Yan
Keyword(s):  
Hydrogen Peroxide ◽  
Fuel Cell ◽  
High Performance ◽  
Direct Reduction ◽  
Redox Couple ◽  
Cathode Potential ◽  
Mixed Potential

We propose to create the cathode potential by introducing a redox couple to the cathode while using hydrogen peroxide to chemically charge the redox ions, which eliminates the mixed potential associated with direct reduction of hydrogen peroxide.

Sign in / Sign up

Export Citation Format

Share Document