高碘酸钠氧化罗丹明B催化光度法测定电镀废水中金

Catalytic spectrophotometric determination of gold in electroplating waste water based on oxidation of sodium iodate on rhodamine B

在1.0 mol/L H_2SO_4介质中,金(Ⅲ)对高碘酸钠氧化罗丹明B的褪色反应具有催化作用,褪色程度与金(Ⅲ)量在一定范围内呈线性关系,以此建立了一种测定金(Ⅲ)的催化光度法。该法褪色溶液的最大吸收波长为560 nm,检出限为1.21×10^(-4)μg/mL,在50 mL溶液中金(Ⅲ)量在0～1.8μg范围与吸光度的减少呈线性关系,常见的离子和一些稀土离子不干扰测定,Ru (Ⅲ),Fe^(3+),Rh(Ⅲ)干扰严重,但可以利用三唑螯合树脂分离而消除。方法用于电镀废水中金(Ⅲ)的测定,相对标准偏差为2.0%,加标回收率为104%。

Based on the catalyzing effect of Au（Ⅲ） on the oxidation reaction of rhodamine B by sodium iodate in 1.0 mol/L H2SO4 ,a spectrophotometric method for the determination of Au（Ⅲ） has been developed. The results show that the maximum absorption wavelength of the fading solution is at 560nm. The detection limit for Au（Ⅲ） is found as 1.21 × 10^-4 μg/mL,and the linear range as 0-1.8 μg/50 mL. Larger quantities of common ions and some rare-earth ions do not interfere,but Ru（Ⅲ）,Fe^3＋ and Rh（Ⅲ） affect the determination seriously. The interference from Ru（Ⅲ）,Fe^3＋ and Rh（Ⅲ）can be eliminated by separation of them with trizole chelating resin. For analysis of electroplating waste water, the relative standard deviation and recovery rate are 2. 0% and 104% ,respectively.