阴离子树脂分离富集光度法测定尾矿中微量钼

研究了717型阴离子交换树脂柱分离-富集钼的条件,建立了分光光度法测定尾矿中微量钼的方法。在pH 7.5的条件下,钼以MoO42-形式被树脂定量吸附后,采用体积比1:1的2 mol/L HNO3和0.5 mol/L NH4NO3混合溶液洗脱,消除了绝大部分共存离子的干扰。结果表明,采用硫氰酸盐光度法,体系的最大吸收波长为460 nm,线性范围为0～120.0μg/L,检出限为1.3μg/L。对实际样品测定结果与ICP-AES法相符,6次测定值的RSD=3.3%,加标回收率在96.2%～105.7%之间。

Spectrophotometric determination of micro amounts of molybdenum in tailings after separation and enrichment by anion resins

The conditions of separation and enrichment of micro amounts of molybdenum with 717 type anion exchange resin column have been studied.A method for spectrophotometric determination of micro amounts of molybdenum in tailings is proposed.Under the conditions of pH 7.5,molybdenum as MoO42-was separated and enriched by the ion exchange resin,then eluted by mixed solution of 2 mol/L HNO3 and 0.5 mol/L NH4NO3 with the volume ratio 1:1,which eliminated most of the interference from coexisting ions.The results showed that the maximum absorption wavelength of the system was 460 nm,the linear range is 0.0-120.0 μg/L and the detection limit for Mo(Ⅵ) is 1.3 μg/L with thiocyanide spectrophotometry.The method was successfully used to determine micro amounts of molybdenum in real samples,and its results were in good agreement with those provided by ICP-AES method.The relative standard deviation was 3.3%(n=6) and the recoveries of samples were between 96.2% and 105.7%.