Catalytic Kinetic Spectrophotometric Determination of Trace Amount of Selenium in Tailings

In a 1.0 mol·L-1 HCl medium and heated in a water bath at 90 ℃ for 10 min, the oxidative color-fading reaction of methyl red with H2O2 was remarkably catalyzed by the presence of trace amount of Se(Ⅳ). Based on this fact, a catalytic kinetic spectrophotometric method for determination of trace amount of Se(Ⅳ) was proposed. Value of molar absorptivity was found to be 4.351×105L·mol-1·cm-1. Beer′s law was held in the range of 0.004-0.06 mg·L-1, with detection limit (3s/k) of 2.23×10-2μg ·L-1. In analyzing samples of tailings by this method, values of recovery and RSD′s (n=11) found were in the ranges of 96.7%-99.4% and 2.4%-2.5% respectively.