罗丹明B褪色光度法测定微量溴酸根离子的研究

Study on Determination of Trace Bromate by Decolor Spectrophotometric Method of Rhodamine B

研究了罗丹明B与B rO3-的褪色反应,确定了最佳反应条件,建立了一种光度法测量微量溴酸根离子的新方法.结果表明：在盐酸介质中溴酸根氧化罗丹明B褪色,最大吸收波长为556 nm,方法的表观摩尔吸光系数ε5′56=1.5×10^5L.mol^-1.cm^-1,检出限为1.12×10^-8g.mL^-1,线性范围为0.0-18.0μg.（25 mL）^-1.用于化学试剂中溴酸根离子的测定,结果满意.

A new method for the determination of trace bromate is proposed in this paper.The optimum conditions for the oxidation of rhodamine B by bromate in hydrochloric acid medium are studied.The maximum absorption peak is located at 556 nm with an apparent molar absorptivity of 1.5×10 ^5 L·mol^-1 ·cm^-1.The detection limit is 1.12×10^-8 g·mL^-1 and the linear range is 0.0～18.0 μg·（25 mL）^-1 of bromate.The proposed method has been applied in determining of trace bromate in chemical reagents with satisfactory results.