有机络合剂对锑(Ⅲ)─水杨基荧光酮─OP显色体系的影响

Effects of Organic Complexing Reagents the Sb(Ⅲ)-Salicylfluorone-OP Colour system

在０．０７５～０．１５ｍｏｌ／ＬＨ２ＳＯ４介质中，Ｓｂ（Ⅲ）与水杨基荧光酮和ＯＰ形成有色络合物，最大吸收波长为５２５ｎｍ，摩尔吸光系数为１．５９ｘ１０５，当在体系中分别加入１０ｍｇ１６种不同有机络合剂时，其中１．２－环已烷二胺四乙酸和亚氨基二乙酸使体系吸光度明显降低。其余对吸光度无明显影响。α－羟基异丁酸、磺基水杨酸、甘露酸和丙二酸分别对Ｃｕ２＋，Ｚｎ２＋，Ｃｄ２＋，Ｐｂ２＋，Ａｌ（Ⅲ）。Ａｓ（Ⅴ），Ｖ（Ⅴ），Ｚｒ（Ⅳ），Ｗ（Ⅵ），Ｓｎ（Ⅳ）和Ｆｅ（Ⅲ）等的允许量有明显提高，方法用于纯铝和铝合金中微量锑的测定，结果满意。

In the medium of H2SO4(0.075-0.15 mol/L) antimony(Ⅲ) reacted with salicylfluorone and OP to form a colour ternary complex,which appeared a maximum absorbance at 525nm and the molar absorptivity was 1.59×105L·mol-1·cm-1. Most kinds(totally 16) of the organic complexing reagents(10mg for each)did not influence on the absorbance of this colour system distinctly, but 1,2-cyclohexydiamonotetraacetic acid or iminodiacetic acid decreased the absorbance obviously. In the pre- sence of α-hydroxyisobutric acid,sulfosalicylic acid, mamnnitol or propane diacid, the tolerable amounts of coexisting elements, such as Cu2+,Zn2+,Cd3+, Pb2+, Al(Ⅲ), as(Ⅲ), As(Ⅴ), v(Ⅴ), Zr(Ⅳ), W(Ⅵ), Sn4+ and Fe3+ etc. were increased evidently. The proposed method has been applied to determine the trace antimony in pure aluminium and aluminium alloys with satisfactory results.