Accession Number : AD0709309

Title :   RELATIVE RATE CONSTANTS FOR REACTIONS OF HYDROXYL RADICALS FROM THE REACTION OF Fe(II) OR Ti(III) WITH H2O2,

Corporate Author : DEFENCE RESEARCH ESTABLISHMENT OTTAWA (ONTARIO)

Personal Author(s) : Armstrong,W. A.

Report Date : 06 MAR 1969

Pagination or Media Count : 9

Abstract : In an attempt to clarify the reactions of ferrous sulfate and titanous sulfate with hydrogen peroxide, a novel method has been developed to determine the relative rate constants for reactions of the oxidizing species generated in these systems. These species react with hydrogen peroxide to give perhydroxyl radicals which combine with titanium(IV) ions to form the relatively stable TiOO.(3+) radical. This radical gives a strong electron spin resonance signal and the competition between hydrogen peroxide and a scavenger for the oxidizing species can be followed by measuring the amplitude of this signal in the presence of various concentrations of scavenger. The relative rate constants calculated in this way for both the Fe(II)-H2)2 and Ti(III)-H2O2 systems at pH 1.0 agree with those reported for the reactions of hydroxyl radicals in gamma-irradiated thymine solutions. This supports the view that hydroxyl radicals are formed in these cases. Scavengers investigated were thymine, methanol, ethanol, formic acid, acetic acid, chloride ion, and several amino acids. (Author)

Descriptors :   (*HYDROGEN PEROXIDE, CHEMICAL REACTIONS), (*IRON COMPOUNDS, CHEMICAL REACTIONS), (*TITANIUM COMPOUNDS, CHEMICAL REACTIONS), REACTION KINETICS, FREE RADICALS, ELECTRON PARAMAGNETIC RESONANCE, SULFATES, PH FACTOR, CANADA

Subject Categories : Inorganic Chemistry

Distribution Statement : APPROVED FOR PUBLIC RELEASE