基于在硫酸介质中,镉能催化溴酸钾氧化甲基红的褪色反应,建立了催化分光光度法测定痕量镉的新方法。方法的线性范围为0.02—0.50μg/mL,检出限6.7×10-3μg/mL。RSD为2.92%、3.54%,样品加标回收率为96.0%、103.5%。该方法简便快速,常见物质干扰小,用于环境水样痕量镉的测定,结果满意。 Based on the fact that cadmium can catalyze the discoloration of methyl red by potassium bromate in sulfuric acid medium, a new catalytic spectrophotometric method for the determination of trace cadmium was established. The linear range of the method was 0.02-0.50μg / mL with the detection limit of 6.7 × 10-3μg / mL. The RSDs were 2.92% and 3.54%, respectively. The spiked recoveries were 96.0% and 103.5% respectively. The method is simple and rapid, with less common interferences and is used for the determination of trace cadmium in environmental water samples with satisfactory results.