溶剂浮选三元缔合物光度法测定痕量铬(Ⅵ)的研究  

Study on the Determination of Trace Cr(Ⅵ) by Solvent Floatation Ternary Associated Complex Spectrophotometry

作　　者：闫永胜[1] 黄卫红[1] 陆晓华[1] 

机构地区：[1]华中科技大学环境科学与工程学院,武汉430074

出　　处：《分析科学学报》2004年第2期157-159,共3页Journal of Analytical Science

摘　　要：本文利用酸性条件下,质子化的3,5 Br2 PADAP(3,5 Br2\|PADAPH3+3)能与Cr2O2-7及SCN-发生三元缔合反应生成Cr2O2-7·3,5 Br2 PADAPH3+3·SCN-,该缔合物在620nm波长处有最大吸收,且易溶于有机溶剂,建立了溶剂浮选测定痕量铬(Ⅵ)新方法。本法的灵敏度为ε620=3.1×105L·mol-1·cm-1,检出限为0.5μg·L-1。测定了人发中痕量铬,结果满意。A method to determine trace Cr(Ⅵ) by solvent floatation has been developed. The method is based on the fact that the ternary associuted complex of (Cr_2O^(2-)_7·3, 5-Br_2-PADAPH^(3+)_3·SCN^-,) which is the procluct of the chemical reaction between 3,5-Br_2-PADAPH_3^(3+)(protonized 3, 5-Br_2-PADAP in acid condition ) , Cr_2O^(2-)_7 and SCN^-, has maximum absorption at the wavelength of 620 nm and is easily dissolved in organic solvent. The method has a high sensitivity ( ε_(620)=3.1×10~5 L·mol^(-1)·cm^(-1) ) and the detection limit of Cr is (0.5 μg)·L^(-1). Trace Cr in human hair has been determined and the result is satisfactory.

关 键 词：铬(Ⅵ) 痕量分析 三元缔合物 溶剂浮选光度法 

分 类 号：O614.611[理学—无机化学] O657.3[理学—化学]