【摘要】 采用流动注射技术进行痕量钪的离子交换分离富集 ,在 0 .40mol·L- 1 HBr介质中 ,Sc3+ 与Br- 形成络阴离子 ,被离子交换树脂交换富集 ,用 0 .2 5mol·L- 1 HNO3 1 5 %硫脲溶液洗脱 ,用对氯偶氮氯膦 (CPA pCl)分光光度法测定。有色络合物的最大吸收波长为 615nm ,钪的质量浓度在 0～ 10 0 0 μg·L- 1 范围内符合比耳定律 ,方法的检出限为 1.2 μg·L- 1 。经分离后 ,钪的测定灵敏度可提高数倍 ,大量共存离子不干扰钪的测定。该法已应用于煤矸石痕量钪的测定更多还原

【Abstract】 A method for the determination of trace scandium by chlorophosphonazo-pCl （CPA-pCl） spectrophotometry after separation and preconcentration with flow injection ion exchange was studied. In the medium of 0.40 mol·L^-1 hydrobromic acid, Sc³⁺ reacts with Br^- to form an anion complex which is then adsorbed on the column of alkali anion exchange resin. The anion complex is desorbed from the column with solution of 0.25 mol·L^-1 nitric acid-1.5% thiourea and it reacts with CPA-pCl to form a color complex for spectrophotometric determination. The maximum absorption wavelength is 615 nm. Beer′s law is obeyed in the concentration range of 0～1000 μg·L^-1 for scandium （Ⅲ）, and the detection limit of the method is 1.2 μg·L^-1. The sensitivity for the determination of scandium can be improved for several times, and a lot of co-ions do not disturb the determination of scandium after separation and preconcentration. The method has been applied to the determination of trace scandium in coal gangue with satisfactory results.更多还原