【摘要】 合成了新型偶氮显色剂5-[2-(5-乙基-1,3,4-噻二唑)偶氮]-8-羟基喹啉(ETADQ),研究了它与铜的显色反应。结果表明:在pH 5.0~7.0的KH2PO4-NaOH缓冲溶液中试剂与铜离子迅速形成一种稳定的黄色络合物,10 min后吸光度达到最大值,络合物的摩尔比组成为1∶1,最大吸收波长位于540 nm处,表观摩尔吸光系数ε=8.1×104L.mol-1.cm-1。铜离子在3.0×10-6~2.2×10-5mol/L范围内服从比尔定律,相关系数r=0.9985。用于测定矿石和合金样品中的微量铜,相对标准偏差为0.79%~4.52%,结果与认定值相吻合。更多还原

【Abstract】 The synthesis of 5-[2-(5-ethyl-1,3,4-thiodiazole)azo]-8-hydroxyquinoline(ETADQ) and its color reaction with copper(Ⅱ) are studied.The results show that the reagent ETADQ reacts with Cu(Ⅱ) to form a stable yellow complex(1∶1) in the medium of KH2PO4-NaOH buffer solution at pH 5.0-7.0 and the maximum absorption wavelength og the complex is at 540 nm with the apparent molar absorptivity of 8.1×104 L·mol-1·cm-1.Beer’s law is obeyed in the range of 3.0×10-6-2.2×10-5 mol/L for copper with the correlation coefficient of 0.998 5.The method has been applied to the determination of copper in ore and alloy samples,with the relative standard deviation of 0.79%-4.52%.The determination results are agreement with the certified values.更多还原