硫酸酸性溶液中における塩素酸イオンとクロム(III)イオンとの反応

抄録

By considering material balance of chlorine and effects of concentrating ratio of chrominum (III) ion to chlorate ion in sulfuric acid solution, it was found that products of th e reaction between chlorate ion and chrominum(III) ion were chlorine dioxide, chlorine and chrominum (VI) ion. At various conc. ratios of chlorate ion to chrominum(III) ion in 8 mol/l sulfuric acid solution, the main reaction was represented by the equation (1) (Table 1).
6ClO₃- + 2Cr³⁺ + H20 = 6ClO₂ + Cr₂O₇^2- + 2H + (1)
Chlorine dioxide was reduced to chloride ion with chrominum(III) ion in sulfuric acid solution (Fig.1 and Table 2). The formation of chlorine could be explained by assuming that chlorine didxide first reduced to chloride ion and this chloride reacted with chlorate in sulfur ic acid solution (Table 3 and Table 4). It was found that Fe(III) ion in the presence of chrominum (III) ion promoted the formation of chlorine dioxide and depressed that of chlorine (Fig.2).