The Lead Dioxide Anode. I. A Kinetic Study of the Electrolytic Oxidation of Cerium(III) and Manganese(II) in Sulfuric Acid at the Lead Dioxide Electrode

The electrolytic oxidation reactions of cerium(III) and manganeseII) in sulfuric acid have been used as probes to investigate the mechanism of the lead dioxide anode. The kinetics observed for such reactions at the lead dioxide surface provide no direct support for the proposal that the lead dioxide anode functions by a sequential 'two-step' mechanism (heterogeneous chemical oxidation of solution species followed by electrochemical oxidation of the reduced lead dioxide surface); rather the kinetics show characteristics similar to those observed previously for the oxidation of cerium(III) and manganese(II) at the platinum electrode, suggesting that the lead dioxide surface functions as a simple, 'inert' electron-transfer agent.

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The Lead Dioxide Anode. II. The Kinetics and Participation of the Lead Dioxide Electrode in Electrochemical Oxidation Reactions in Sulfuric Acid

Australian Journal of Chemistry ◽

10.1071/ch9891527 ◽

1989 ◽

Vol 42 (9) ◽

pp. 1527 ◽

Cited By ~ 3

Author(s):

TH Randle ◽

AT Kuhn

Keyword(s):

Sulfuric Acid ◽

Electrochemical Oxidation ◽

Maximum Rate ◽

Lead Dioxide ◽

Chemical Oxidation ◽

Oxidation Reactions ◽

Electrochemical Regeneration ◽

Electrode Surfaces ◽

Lead Dioxide Electrode ◽

Lead Dioxide Anode

Lead dioxide is a strong oxidizer in sulfuric acid, consequently electrochemical oxidation of solution species at a lead dioxide anode may occur by a two-step, C-E process (chemical oxidation of solution species by PbO2 followed by electrochemical regeneration of the reduced lead dioxide surface). The maximum rate of each step has been determined in sulfuric acid for specified lead dioxide surfaces and compared with the rates observed for the electrochemical oxidation of cerium(III) and manganese(II) on the same electrode surfaces. While the rate of electrochemical oxidation of a partially reduced PbO2 surface may be sufficient to support the observed rates of CeIII and MnII oxidation at the lead dioxide anode, the rate of chemical reaction between PbO2 and the reducing species is not. Hence it is concluded that the lead dioxide electrode functions as a simple, 'inert' electron-transfer agent during the electrochemical oxidation of CellI and MnII in sulfuric acid. In general, it will most probably be the rate of the chemical step which determines the feasibility or otherwise of the C-E mechanism.

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The electrochemical Peltier heat for the adsorption and desorption of hydrogen on a platinized platinum electrode in sulfuric acid solution

Journal of Electroanalytical Chemistry ◽

10.1016/0022-0728(85)85058-0 ◽

1985 ◽

Vol 193 (1-2) ◽

pp. 135-143 ◽

Cited By ~ 29

Author(s):

Shigeo Shibata ◽

Masae P. Sumino

Keyword(s):

Sulfuric Acid ◽

Acid Solution ◽

Sulfuric Acid Solution ◽

Platinum Electrode ◽

Adsorption And Desorption ◽

Platinized Platinum ◽

Electrochemical Peltier Heat

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The behaviour of lead dioxide electrodes in acidic sulfate electrolytes

Australian Journal of Chemistry ◽

10.1071/ch9810247 ◽

1981 ◽

Vol 34 (2) ◽

pp. 247 ◽

Cited By ~ 7

Author(s):

DB Matthews ◽

MA Habib ◽

SPS Badwal

Keyword(s):

Sulfuric Acid ◽

Ammonium Sulfate ◽

Discharge Capacity ◽

Lead Dioxide ◽

Active Material ◽

Cycle Number ◽

Vehicle Propulsion ◽

Rate Of Increase ◽

Pbo2 Electrode ◽

Acidic Sulfate

The variation of discharge capacity during charge-discharge cycling of a PbO2 electrode, prepared by pressing PbO2 powder onto a smooth lead disc, in sulfuric acid and acidic ammonium sulfate solutions of various concentrations was investigated by the potentiodynamic technique. The discharge capacity was found to increase with cycle number in 0.05-4.3 H2SO4; this was explained in terms of the increase in porosity of the electrode with cycling. The rate of increase was highest in a 1 mol dm-3 solution. The presence of ammonium sulfate decreased the discharge capacity at all concentrations of sulfuric acid except for the 1 mol dm-3 solution where it caused a small increase in capacity. The morphology of the electrode was studied by scanning electron microscopy and the results are correlated with the discharge capacity. These results indicated that a solution of composition 0.5 mol dm-3 ammonium sulfate and 1.0 mol dm-3 sulfuric acid will produce a greater utilization of positive plate active material (PbO2) during discharge. This result, taken together with the results of earlier studies on lead in acidic sulfate electrolytes, points to the possibility of a Pb/H2SO4,/PbO2 battery for electric-vehicle propulsion.

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Lead Dioxide Anode for Commercial Use

Journal of The Electrochemical Society ◽

10.1149/1.2428754 ◽

1958 ◽

Vol 105 (2) ◽

pp. 100 ◽

Cited By ~ 14

Author(s):

J. C. Grigger ◽

H. C. Miller ◽

F. D. Loomis

Keyword(s):

Lead Dioxide ◽

Commercial Use ◽

Lead Dioxide Anode

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Biodegradation of phenol and catechol in cloud water: comparison to chemical oxidation in the atmospheric multiphase system

Atmospheric Chemistry and Physics ◽

10.5194/acp-20-4987-2020 ◽

2020 ◽

Vol 20 (8) ◽

pp. 4987-4997 ◽

Cited By ~ 1

Author(s):

Saly Jaber ◽

Audrey Lallement ◽

Martine Sancelme ◽

Martin Leremboure ◽

Gilles Mailhot ◽

...

Keyword(s):

Aqueous Phase ◽

Chemical Oxidation ◽

Cloud Water ◽

Multiphase System ◽

Data Sets ◽

Biological Processes ◽

Atmospheric Conditions ◽

Oxidation Reactions ◽

Atmospheric Models ◽

Degradation Rates

Abstract. The sinks of hydrocarbons in the atmosphere are usually described by oxidation reactions in the gas and aqueous (cloud) phases. Previous lab studies suggest that in addition to chemical processes, biodegradation by bacteria might also contribute to the loss of organics in clouds; however, due to the lack of comprehensive data sets on such biodegradation processes, they are not commonly included in atmospheric models. In the current study, we measured the biodegradation rates of phenol and catechol, which are known pollutants, by one of the most active strains selected during our previous screening in clouds (Rhodococcus enclensis). For catechol, biodegradation is about 10 times faster than for phenol. The experimentally derived biodegradation rates are included in a multiphase box model to compare the chemical loss rates of phenol and catechol in both the gas and aqueous phases to their biodegradation rate in the aqueous phase under atmospheric conditions. Model results show that the degradation rates in the aqueous phase by chemical and biological processes for both compounds are similar to each other. During day time, biodegradation of catechol is even predicted to exceed the chemical activity in the aqueous phase and to represent a significant sink (17 %) of total catechol in the atmospheric multiphase system. In general, our results suggest that atmospheric multiphase models may be incomplete for highly soluble organics as biodegradation may represent an unrecognized efficient loss of such organics in cloud water.

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Electrocatalytic degradation of the herbicide metamitron using lead dioxide anode: influencing parameters, intermediates, and reaction pathways

Environmental Science and Pollution Research ◽

10.1007/s11356-019-05868-7 ◽

2019 ◽

Vol 26 (26) ◽

pp. 27032-27042 ◽

Cited By ~ 1

Author(s):

Yang Yang ◽

Leilei Cui ◽

Mengyao Li ◽

Liman Zhang ◽

Yingwu Yao

Keyword(s):

Lead Dioxide ◽

Reaction Pathways ◽

Electrocatalytic Degradation ◽

Lead Dioxide Anode ◽

Influencing Parameters

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Plasma Electrolytic Oxidation of Titanium in H2SO4–H3PO4 Mixtures

Coatings ◽

10.3390/coatings10020116 ◽

2020 ◽

Vol 10 (2) ◽

pp. 116 ◽

Cited By ~ 1

Author(s):

Bernd Engelkamp ◽

Björn Fischer ◽

Klaus Schierbaum

Keyword(s):

Sulfuric Acid ◽

Phosphoric Acid ◽

Oxide Layer ◽

Plasma Electrolytic Oxidation ◽

Phase Changes ◽

Crystal Phase ◽

Plasma Discharges ◽

X Ray ◽

Electrolytic Oxidation ◽

Plasma Electrolytic

Oxide layers on titanium foils were produced by galvanostatically controlled plasma electrolytic oxidation in 12.9 M sulfuric acid with small amounts of phosphoric acid added up to a 3% mole fraction. In pure sulfuric acid, the oxide layer is distinctly modified by plasma discharges. As the time of the process increases, rough surfaces with typical circular pores evolve. The predominant crystal phase of the titanium dioxide material is rutile. With the addition of phosphoric acid, discharge effects become less pronounced, and the predominant crystal phase changes to anatase. Furthermore, the oxide layer thickness and mass gain both increase. Already small amounts of phosphoric acid induce these effects. Our findings suggest that anions of phosphoric acid preferentially adsorb to the anodic area and suppress plasma discharges, and conventional anodization is promoted. The process was systematically investigated at different stages, and voltage and oxide formation efficiency were determined. Oxide surfaces and their cross-sections were studied by scanning electron microscopy and energy-dispersive X-ray spectroscopy. The phase composition was determined by X-ray diffraction and confocal Raman microscopy.

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