离子液体气浮溶剂浮选分光光度法测定环境水样中的痕量镉

Determination of Trace Cadmium(Ⅱ) in Environmental Water Samples by Spectrophotometry after Solvent Sublation with Ionic Liquid

以等体积的离子液体1-丁基-3-甲基咪唑六氟磷酸盐([Bmim]PF6)和乙酸乙酯(EA)的混合溶剂为浮选剂,以抗坏血酸为掩蔽剂,建立了离子液体气浮溶剂浮选分光光度法测定环境水样中痕量镉的新方法.在pH4.8的溶液中,浮选时间为10 min、氮气流速为45 mL.min-1时,缔合物的最大吸收波长为553 nm.镉的线性范围为0.28-56.0μg.L-1,线性回归方程为A=0.2147+1.7602c(μg.L-1),表观摩尔吸光率为2.53×105L.mol-1.cm-1,检出限为0.15μg.L-1,用于环境天然水中痕量镉的测定.

The ionic liquid（1-butyl-3-methylimidazolium hexafluorophosphate,PF6） was mixed with ethyl acetate in the same volume and used as flotation agent.A new determination method of trace Cd（Ⅱ） in environmental water samples by spectrophotometry after ionic liquid solvent sublation was established using ascorbic acid as eliminating reagent.In the solution at pH 4.8,when the flotation time was 10 min and the flow rate of gas was 45 mL·min-1,the maximum absorption wavelength of complex was 553 nm.The linear range was 0.28-56.0 μg·L-1.The linear regression equation was A=0.2147＋1.7602c（μg·L-1）,with apparent molar absorption coefficient was 2.53×105 L·mol-1·cm-1.The limit of detection was 0.15 μg·L-1 mol·L-1.This method was applied to analyse trace Cd（Ⅱ） in nature water.