测定痕量铊的纳米氧化铝吸附分离-镉试剂2B分光光度法

摘要

It was investigated that the color reaction of thallium with Cadion 2B in the NH3-NH4Cl medium at pill 1.5-12.5 with Triton X-100. Thallium （Ⅲ） and Cadion 2B form a red complex with apparent molar absorptivity 7.29 ×10^4 L·mol-1·cm-1 at 500 nm of detection wave-length. The calibration equation is A = 0.0139 C ＋0.0032 with a correlation coeflqcient of 0.9993, and the calibration graph was linear in the range of 0-800μg/L for thallium. A method for the determination of trace amount of thallium by spectrophotometry was established using nano- 3＇ -A1,.O3 as an adsorption-separating material. The method has been successfully applied to the determination of trace thallium in some environmental samples and the certified reference material polymetallic nodule （GBW07296） in aqueous solution with recoveries of 96- 102%. The relative standard deviations （n=7） are less than 2.4 %. The proposed method is rapid.%研究了在pH11．5～12．5的NH3-NH4Cl介质和TritonX-100存在下，镉试剂2B与铊（Ⅲ）的显色反应。铊（Ⅲ）与镉试剂2B形成红色配合物，在测定波长500nm处，表观摩尔吸光系数为7．29X10·L·mol-1·cm-1，线性方程为A=0．0139C＋0．0032，相关系数是0．9993，线性范围是肛800μg／L。建立了采用纳米氧化铝吸附铊（Ⅲ），与其他干扰元素分离，在水相体系快速、准确测定多金属结核GBW07296和环境水样中痕量铊的方法，回收率为96-102％，相对标准偏差不大于2．4％。