Ruthenium and Arsenic Electrode Potentials in Fused LiCl–KCl Eutectic

1972 ◽  
Vol 50 (23) ◽  
pp. 3911-3912 ◽  
Author(s):  
T. Folkman ◽  
James A. Plambeck
Keyword(s):  
Platinum Electrode ◽  
Ionic Species ◽  
Potential Range ◽  
Dilute Solutions ◽  
Electrode Potentials

Electrode potentials of the Ru(III)/Ru(0) and As(III)/As(0) systems were measured in dilute solutions of the ionic species in fused LiCl–KCl eutectic at 450 °C. Standard molar electrode potentials of these couples of −0.107 ± 0.007 V and −0.460 ± 0.017 V against a standard molar platinum electrode were calculated. The As(V)/As(III) potential was found to be beyond the potential range of the melt.

Thallium and Tin Electrode Potentials in Fused LiCl–KCl Eutectic

1973 ◽  
Vol 51 (11) ◽  
pp. 1693-1696 ◽  
Author(s):  
Joseph M. Shafir ◽  
James A. Plambeck
Keyword(s):  
Reference Electrode ◽  
Ionic Species ◽  
Dilute Solutions ◽  
Electrode Potentials

Electrode potentials of thallium and tin couples were measured in dilute solutions of the ionic species in fused LiCl–KCl eutectic, at 450 °C. Standard molar electrode potentials of the Tl(III)/Tl(I) and Sn(IV)/Sn(II) couples are +0.155 and −0.310 V against a standard molar platinum reference electrode (s.m.p.e.). The standard potentials of the Tl(III)/Tl(0) and Sn(IV)/Sn(0) couples were calculated to be −0.385 and −0.964 V, respectively, vs. the s.m.p.e.

Gallium and indium electrode potentials in fused LiCl–KCl eutectic

1970 ◽  
Vol 48 (13) ◽  
pp. 2131-2132 ◽  
Author(s):  
Joseph M. Shafir ◽  
James A. Plambeck
Keyword(s):  
Ionic Species ◽  
Oxidation States ◽  
Dilute Solutions ◽  
Electrode Potentials ◽  
Salt Systems ◽  
Indium Electrode ◽  
Fused Salt

Electrode potentials of indium and gallium couples have been measured in dilute solutions of the ionic species in fused LiCl–KCl eutectic at 450 °C. Standard molar electrode potentials of the observed couples are −1.210, −0.944, and −1.136 V against a standard molar platinum reference for the In(I)–In(0), In(III)–In(I), and Ga(III)–Ga(0) couples, respectively. These oxidation states and potentials are compared with previous work in this and other fused salt systems.

Beryllium and scandium electrode potentials in fused LiCl–KCl eutectic

1968 ◽  
Vol 46 (6) ◽  
pp. 929-931 ◽  
Author(s):  
James A. Plambeck
Keyword(s):  
Ionic Species ◽  
Dilute Solutions ◽  
Electrode Potentials

Electrode potentials of the Be(II)–Be(0) and Sc(III)–Sc(0) systems were measured in dilute solutions of the ionic species in fused LiCl–KCl eutectic at 450 °C. Standard molar electrode potentials of these couples of −2.039 ± 0.013 V and −2.553 ± 0.015 V against a standard molar platinum reference were calculated. It was shown by voltammetric and chronopotentiometric methods that the equilibrium [Formula: see text] suggested by previous authors was not significant in this medium.

Reversible electrode potentials for formation of solid and liquid chlorozirconate and chlorohafnate compounds

1993 ◽  
Vol 71 (9) ◽  
pp. 1283-1289 ◽  
Author(s):  
G.J. Kipouros ◽  
S.N. Flengas
Keyword(s):  
Thermal Decomposition ◽  
Alkali Metal ◽  
Electrochemical Behaviour ◽  
Thermochemical Data ◽  
Dilute Solutions ◽  
Alkali Metal Chlorides ◽  
Metal Chlorides ◽  
Electrode Potentials ◽  
Standard Electrode Potentials

The standard electrode potentials for the formation of the pure solid and molten compounds Li2ZrCl6, Li2HfCl6, Na2ZrCl6, Na2HfCl6, K2ZrCl6, K2HfCl6, Cs2ZrCl6, and Cs2HfCl6 have been calculated from measured vapour pressures corresponding to their thermal decomposition at equilibrium and from available thermochemical data. Reversible potentials for the formation of Na2ZrCl6 and of K2ZrCl6 in solution according to the reaction[Formula: see text]where A is Na or K, have been calculated from available equilibrium vapour pressures as functions of the mole fractions of the alkali hexachlorocompounds. Standard potentials for the above reaction and "formal" potentials are also given. The latter are useful in predicting the electrochemical behaviour of dilute solutions of the hexachlorozirconates in alkali metal chlorides.

scholarly journals Elements in the Interpretation of Platinum Electrode Potentials in Biological Treatment

1992 ◽  
Vol 26 (5-6) ◽  
pp. 1335-1344 ◽  
Author(s):  
A. Heduit ◽  
D. R. Thevenot
Keyword(s):  
Dissolved Oxygen ◽  
Biological Treatment ◽  
Platinum Electrode ◽  
Surface Characteristics ◽  
Electrode Potentials ◽  
Zero Current ◽  
Experimental Values ◽  
Mixed Potentials ◽  
Ionic Forms ◽  
Current Potential

The zero current potential of a platinum electrode in a biological medium (wastewater, activated sludge) is strongly dependent on the surface characteristics of the metal. It is also influenced by pH (probably Pt/PtO system), dissolved oxygen (O2/OH- system), and ionic forms of nitrogen (NO2-/NH4+ and NO3-/NO2-systems). The experimental values of the coefficients relating the stabilized potential of a platinum electrode to the logarithm of the concentration of the elements under consideration (Nernst equations) are significantly different from the thermodynamic coefficients corresponding to each reaction. The platinum is thus not in equilibrium with the dissolved redox reactants and is likely subject to mixed potentials in which the adsorbed components play an important role.

Some thermodynamic and kinetic properties of H2SO4–H3PO4–H2O–Fe(III) system

2021 ◽  
pp. 1-9
Author(s):  
Ya.G. Avdeev ◽  
Keyword(s):  
Diffusion Coefficients ◽  
Arrhenius Equation ◽  
Platinum Electrode ◽  
Molar Fraction ◽  
Redox Couple ◽  
Kinetic Properties ◽  
Cyclic Voltammogram ◽  
Electrode Potentials ◽  
Half Wave ◽  
Sulfate Complexes

The values of the electrode potentials of the redox couple Fe(III) / Fe(II) and the half-wave potentials of the reactions Fe3+ + e– = Fe2+ и Fe2+ — e– = Fe3+ on the cyclic voltammogram of a platinum electrode in acid solutions containing Fe(III) salts have been measured to characterize the oxidizing ability of the H2SO4—H3PO4—H2O—Fe(III) system. The values of these experimentally obtained parameters are close. A decrease in the oxidizing ability of H2SO4 and H3PO4 mixtures containing Fe(III) with an increase in the molar fraction of H3PO4 in them occurs due to the formation of Fe(III) complexes with phosphate anions which are inferior to their hydrate and sulfate complexes in the oxidizing ability. The temperature coefficients of the electrode potential (dE / dt) of the redox couple Fe(III) / Fe(II) in the H2SO4—H2O, H2SO4—H3PO4—H2O and H3PO4–H2O systems were determined experimentally. The diffusion coefficients of Fe(III) in the studied solutions were calculated based on the Randles—Shevchik equation. The temperature dependence of the diffusion coefficients of Fe(III) cations is satisfactorily described by the Arrhenius equation. The parameters of this equation are calculated.

scholarly journals ELECTROCHEMICAL OXIDATION OF DIMETHYL SULFONE IN ALKALINE MEDIUM

2018 ◽  
Vol 61 (8) ◽  
pp. 32
Author(s):  
Magomed A. Akhmedov ◽  
Shagabudin Sh. Khidirov ◽  
Madina Yu. Kaparova
Keyword(s):  
Carbon Dioxide ◽  
Electrochemical Oxidation ◽  
Alkaline Medium ◽  
Platinum Electrode ◽  
Base Material ◽  
Physicochemical Analysis ◽  
Infrared Spectrometry ◽  
Potential Range ◽  
Preparative Electrolysis ◽  
Dimethyl Sulfone

In this paper the electrochemical oxidation of dimethyl sulfone (DMSO2) on a platinum electrode in an alkaline medium has been studied by cyclic voltammetry. It is shown that during the electrochemical oxidation of dimethylsulfone in an alkaline medium on a smooth platinum electrode, a significant suppression of the oxygen evolution (O2) occurs in the potential range of E = 1.3-2.0 V. By scanning electron microscopy methods, Raman scattering and infrared spectrometry it is shown that the main substance is the dimethyl disulfone (DMDSO2) during the anodic oxidation of DMSO2 on a platinum electrode. By the preparative electrolysis of aqueous solutions of various concentrations of DMSO2 in 0.1 M NaOH solution at controlled potentials E = 1.6 and 1.8 V it is established that the current yield of the base material is not more than 84%. Based on the data of the physicochemical analysis of the final products of preparative electrolysis, a mechanism is proposed for the formation of dimethyl disulfone in an alkaline medium. It has been shown that the oxidation of dimethyl sulfone proceeds in the oxygen region by breaking C-S bonds in the DMSO2 molecule to form methyl (CH3•) and methylsulfonic (CH3S•(O)2) radicals. It is assumed that the methylsulfone radicals readily dimerize with the formation of stable DMDSO2 molecules and are desorbed in the bulk of the solution, and the methyl radicals bind to the HO radicals to form methanol molecules. The latter is well chemisorbed on the surface of platinum with the formation of adsorbed COH particles that are oxidized on a platinum electrode with the formation and evolution of carbon dioxide (CO2) from the volume of the anolyte solution. The formation of molecules of methanol was identified by the method of chromato-mass -spectrometry, and the emission of carbon dioxide by the gravimetry.

The development of electrochemical methods for determining nanoparticles in the environment. Part I. Voltammetry and in-situ electrochemical scanning tunnelling microscopy (EC-STM) study of FeS in sodium chloride solutions

2014 ◽  
Vol 11 (2) ◽  
pp. 181 ◽  
Author(s):  
M. Marguš ◽  
N. Batina ◽  
I. Ciglenečki
Keyword(s):  
Particle Deposition ◽  
Natural Waters ◽  
Scanning Tunnelling Microscopy ◽  
Potential Range ◽  
Promising Tool ◽  
Electrode Potentials ◽  
Scanning Tunnelling ◽  
Tunnelling Microscopy ◽  
Voltammetric Measurements

Environmental context The dramatic change in physical and chemical characteristics that substances experience at reduced length scales (1–100nm), together with a potential risk of ecotoxicity, are two of the reasons for the scientific interest in nanoparticles. The current understanding of the behaviour and fate of nanoparticles in natural waters is limited because of a lack of efficient methods for their characterisation. Electrochemistry is a promising tool for the determination and characterisation of nanoparticles in the natural environment. Abstract In-situ electrochemical scanning tunnelling microscopy (EC-STM) has been used for the characterisation and determination of FeS nanoparticles (NPs) at a Au(111) electrode in NaCl solutions oversaturated with FeS. In parallel, voltammetric measurements in different electrode systems (Hg and Au) have been conducted. Particle deposition was studied in relation to variations in applied and scanning electrode potentials over a range of 0.1 to –1.5V v. Ag/AgCl. EC-STM images obtained on the Au(111) electrode revealed the presence of FeS NPs, accompanied by a drastic transformation in the electrode’s surface topography during scanning from 0.1 to –1.2V. A majority of FeS NPs (diameter 2–5nm) were detected in the potential range of –0.15 to –0.25V v. Ag/AgCl. The EC-STM results are in very good agreement with previous voltammetric measurements at Hg and Au electrodes. The combination of in-situ EC-STM and cyclic voltammetry complementary techniques appears to be a powerful tool for the characterisation of complex electrochemical systems such as chalcogenide NPs in aqueous solutions.

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