由于偶氮氯膦mN与镍生成蓝色络合物,其吸收峰与稀土仅差15nm,严重干扰测定,故该试剂对镍的充许限量较低。大量硅胶的析出,不但增加分离手续,且对被测元素起包裹作用,影响重现性。本文选用稀硝酸介质,以氨羧络合剂为掩蔽剂,在大量镍、硅离子共存下,直接测定轻稀土,获得较为满意的结果。 Since the chlorophosphonazo mN and nickel blue complexes generated, the absorption peak difference of only 15nm with rare earth, seriously interfere with the determination, so the reagent of the lower allowable limit of nickel. A large number of silica gel precipitation, not only increase the separation procedures, and the measured elements from the package role, affecting reproducibility. In this paper, dilute nitric acid medium was selected to take ammonia carboxylamine complex as a masking agent, a large number of nickel and silicon ions in the coexistence of direct determination of light rare earth, get more satisfactory results.