Electrochemical regeneration of ceric sulphate in an undivided cell

1993 ◽  
Vol 23 (12) ◽  
Author(s):  
J. Been ◽  
C.W. Oloman
Keyword(s):  
Electrochemical Regeneration ◽  
Undivided Cell ◽  
Ceric Sulphate

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

1989 ◽  
Vol 42 (9) ◽  
pp. 1527 ◽  
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.

Electrochemical regeneration of polypyrrole-tailored activated carbons that have removed sulfate

Carbon ◽  
2014 ◽  
Vol 79 ◽  
pp. 46-57 ◽  
Author(s):  
Pin Hou ◽  
Timothy Byrne ◽  
Fred S. Cannon ◽  
Brian P. Chaplin ◽  
Siqi Hong ◽  
...  
Keyword(s):  
Activated Carbons ◽  
Electrochemical Regeneration

Oxidation of phenol and the adsorption of breakdown products using a graphite adsorbent with electrochemical regeneration

2013 ◽  
Vol 92 ◽  
pp. 20-30 ◽  
Author(s):  
S.N. Hussain ◽  
E.P.L. Roberts ◽  
H.M.A. Asghar ◽  
A.K. Campen ◽  
N.W. Brown
Keyword(s):  
Electrochemical Regeneration ◽  
Oxidation Of Phenol

The role played by local pH and pore size distribution in the electrochemical regeneration of carbon fabrics loaded with bentazon

Carbon ◽  
2015 ◽  
Vol 94 ◽  
pp. 816-825 ◽  
Author(s):  
Sandrine Delpeux-Ouldriane ◽  
Mickaël Gineys ◽  
Nathalie Cohaut ◽  
François Béguin
Keyword(s):  
Pore Size Distribution ◽  
Pore Size ◽  
Size Distribution ◽  
Electrochemical Regeneration ◽  
Local Ph ◽  
Carbon Fabrics

scholarly journals Phytochemical Screening and TLC Profile of Fruits and Flowers of Alstonia venenata R. Br.

2016 ◽  
Vol 8 (02) ◽  
Author(s):  
Thomas S. K. ◽  
George E. ◽  
Kunjumon M. ◽  
Thankamani I.
Keyword(s):  
Petroleum Ether ◽  
Dry Weight ◽  
Stem Bark ◽  
Phytochemical Analysis ◽  
Root Bark ◽  
Good Resolution ◽  
Peninsular India ◽  
Spray Reagent ◽  
Hexane Extracts ◽  
Ceric Sulphate

Alstonia venenata R. Br. belonging to the family Apocynaceae is a tall evergreen shrub distributed throughout Peninsular India. Stem-bark, root-bark, fruits and leaves are used by many tribal communities and also in Ayurveda. The study investigates the phytochemical composition of hexane, butanol, methanol and water extracts of Alstonia venenata fruits and flowers as well as the TLC profile of hexane extracts of fruits and flowers. Quantitative data of the wet and dry weight, yields from different solvent fractions and percentage yields were noted. The phytochemical analysis revealed the presence of secondary metabolites such as alkaloids, steroids, terpenoids, saponins, flavonoids, tannins and phenolic compounds from the various extracts. Alkaloids were present in all the fractions tested. Methanol extracts of fruits and flowers showed the presence of major phytoconstituents. TLC profile of hexane extracts of fruits and flowers were developed using anisaldehyde sulphuric acid/ceric sulphate (steroids/terpenoids) and Dragendorff’s spray reagents (alkaloids). Petroleum ether: Chloroform: Methanol (5: 4.5: 0.5) showed good resolution for the hexane extracts of fruit and flower when treated with Dragendorff’s spray reagent. Petroleum ether: Chloroform (1:1) was best for the hexane exacts of flowers and fruits when sprayed with ceric sulphate spray reagent

The effects of high dose rates of ionizing radiations on solutions of iron and cerium salts

1960 ◽  
Vol 255 (1283) ◽  
pp. 490-508 ◽  
Keyword(s):  
Hydrogen Peroxide ◽  
Dose Rate ◽  
Ferrous Sulphate ◽  
High Dose ◽  
Oh Radicals ◽  
Dose Rates ◽  
Reaction Zones ◽  
Constant Dose ◽  
Ceric Sulphate ◽  
Ionizing Radiations

The electron beam generated by a 15 MeV linear accelerator has been employed to induce reactions in aerated aqueous solutions of 1 to 25 mM ferrous sulphate, and of 0⋅1 to 1 mM ceric sulphate. The radiation was delivered in pulses of 1⋅3 μ s duration and over a range of dose rates from 0⋅5 to 20000 rads/pulse. Radiation yields at constant dose rate were compared with the aid of a chemical dose monitor. A system of two thin, widely spaced, irradiation vessels was employed to determine the variation of yield of any one system over successive known ranges of dose rate. The yield of ferric sulphate in the iron system was found to decrease with increasing dose rate in the range 0⋅01 to 10 krads/pulse by an overall factor of 0⋅85, and was appreciably dependent on the initial concentrations of dissolved oxygen and of ferrous sulphate at high dose rates. Yields of hydrogen and of hydrogen peroxide were practically independent of dose rate. The observations have been interpreted on the basis of inter-radical reactions which occur when the reaction zones of neighbouring clusters overlap. The following reactions can account for all the data: OH + Fe 2+ → Fe 3+ + OH ¯ , (1) H + O 2 → HO 2 , (2) H + OH → H 2 O. (7) The values k 1 / k 7 = 0⋅0062, and k 2 / k 7 = 0⋅22 are reasonably consistent with the observations. In the ceric sulphate system the yield of cerous sulphate increases progressively over the range 0⋅01 to 10 krads/pulse by an overall factor of 1⋅4. The data accord with the view that at high dose rates OH radicals react with them selves ultimately to form hydrogen peroxide, in competition with their normal reaction with cerous sulphate.

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