钪-铬天青S-阳离子表面活性剂的显色反应及有机溶剂化效应的研究

Solvation Effects of Organic Solvents on Colour Reactions of Multiconlponent Complexes of Scandium

本文系统地研究了八种有机溶剂对钪(Ⅲ)-铬天青S-长链季铵盐多元络合物显色反应的溶剂化效应。结果表明不加有机溶剂时,Sc-CAS-OtTAB络合物的摩尔吸光系数为1.4×10^(5)升/摩尔·厘米,当适量有机溶剂如甲醇或二甲基甲酰胺存在时,该体系的摩尔吸光系数可提高到3.2×10^(5)升/摩尔·厘米。拟定了可以用于直接测定烯土氧化物和镧钪铁氧体中微量钪的分光光度法。测定了钪多元络合物的组成及溶剂化数,探讨了溶剂化效应的机理。

The solvation effects of organic soivcnts(methol alcohyl,ethyl alcohol,n-propanol, isopropanol, acetone, dimethyl sulfoxide, dimelhylformamide and dioxane)on colour reactions of multicomponcnt complex (MCC) of scandium with chromazurol-S(CAS) and long chain cation surfactants have been systematically investigated.The sensitivity and selectivity of the colour reactions of MCC of scandium can be markedly improved by the solvation effects of organic solvents. The molar absorptivity of the complex Sc-CAS-OtTAB is 1.4× 10^(5) l/mol·cm in the absence of organic solvetn, but it (e) can be risen to 3.2× 10^(5) l/mol·cm in the presence of methyl alcohol or dimethyl formamide. The new highly sensitive and selective colour reactions have been developed as a method for the determination micro amounts of scandium in rare earth oxide and in fcrritc of lanthanum and scandium. The composition of MCC of scandium and its solvation number were determined. The mechanism of the solvation effect has been discussed.