乳化剂OP存在下2,4,6-三卤代偶氮氯膦分光光度法测定钍(Ⅳ)

Spectrophotometric Determination of Thorium(Ⅳ) With 2, 4, 6-Trihalogenated Chlorophosphonazo in the Presence of Emulgent OP

报道了在不同的酸度下乳化剂ＯＰ对２，４，６．三卤代偶氮氯膦与钍（Ⅳ）显色反应抗干扰能力的影响。研究表明：在酸度高达４．８ ｍｏｌ／Ｌ的ＨＣＩ中，乳化剂ＯＰ的加入能明显地提高显色反应的选择性，而灵敏度没有明显降低，三溴偶氮氯膦与钍的显色体系尤其明显。可不经任何分离掩蔽手段直接测定独居石中的钍（Ⅳ）。

The effect of emulgent OP on the selectivity of color reactions Th(Ⅳ)-2,4, 6-trihalogenated chlorophosphonazo (CPA) has been studied. The results showed that in higher acidity medium, the selectivity of color reactions could be improved markedly by adding emulgent OP, especially for 2,4,6- tribromo-chloro- chlorophosphonazo(TBCCPA ) + Th(Ⅳ) color reaction. The Th (Ⅳ) in monazite samples could be determined directly by spectrophotometric method.