Effects of chloride and sulfate on the rate of oxidation of ferrous ion by H2O2.
The rates of oxidation of Fe(II) by H(2)O(2) in the presence of sodium perchlorate, sodium nitrate, sodium chloride and sodium sulfate salts (0-1M) have been compared in the study. Experiments were carried out in a batch reactor, in the dark, at pH <3, 25+/-0.5 degrees C and at controlled ionic strength (< or =1M). The experimental results showed that the rates of oxidation of Fe(II) in the presence of chloride, nitrate and perchlorate were identical. In the presence of sulfate, the rate of oxidation of Fe(II) was faster and depended on the pH and the concentration of sulfate. The pseudo second-order rate constants for the reaction of H(2)O(2) with Fe(2+), FeCl(+) and FeSO(4) were determined as 55+/-1, 55+/-1 and 78+/-3 M(-1) s(-1), respectively.
Truong
Giang Le
GL
Laboratoire de Chimie de l'Eau et de l'Environnement, CNRS UMR 6008, Ecole Supérieure d'Ingénieurs de Poitiers, Université de Poitiers, 40, avenue du Recteur Pineau, Poitiers Cedex 86 022, France.
De Laat
Joseph
J
Legube
Bernard
B
D002712:Chlorides / Q000737:chemistry*; D005290:Ferric Compounds / Q000737:chemistry; D005296:Ferrous Compounds / Q000737:chemistry*; D006861:Hydrogen Peroxide / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D009566:Nitrates / Q000737:chemistry; D010084:Oxidation-Reduction; D010472:Perchlorates / Q000737:chemistry; D013431:Sulfates / Q000737:chemistry*
D002712:Chlorides; D005290:Ferric Compounds; D005296:Ferrous Compounds; D009566:Nitrates; D010472:Perchlorates; D013431:Sulfates; C012036:sodium sulfate; D006861:Hydrogen Peroxide