双硫腙显色分光光度法测定矿样中的重金属铅

Dithizone Color Spectrophotometry for Determination of Heavy Metal Lead in Ore Sample

采用双硫腙显色分光光度法测定矿石中的重金属铅,以双硫腙为螯合剂,使之与铅离子反应生成的带色物质在515 nm处有最大吸光度.在0.02-0.2μg/m L浓度范围内符合朗伯-比尔定律,相关系数r为0.9997,摩尔吸收系数κ为1.06686×105L/mol·cm,检出限量为9.62×10-3μg/m L.实验结果表明：优化条件下,测得原矿中的铅含量为41.23μg/g,相对标准偏差RSD为1.54%（n=6）,加标回收率在97.38%-99.5%之间,该方法适用于矿石中重金属铅的测定.

Dithizone color spectrophotometry is used for determination of heavy metal lead in ores. Colored sub-stances are produced by the reaction between dithizone as a chelating agent and lead ion, which has maximum ab-sorbance at 515 nm. In 0.02-0.02 g/m L, concentration range conforms to the lambert beer＇s law. The correlationcoefficient r is 0.9997. The molar absorption coefficient κ is 1.06686×105L/mol·cm. The limit detection is 9.62×10-3μg/m L. Experimental results show that under the optimized conditions lead content in ore is 41.23 μg/g. Rela-tive standard deviation RSD is 1.54%（n=6）. Standard addition recovery is between 97.38% and 99.5%. This methodis for the determination of heavy metal lead in the ore.