4-(2-噻唑偶氮)连苯三酚光度法测定钢样中钛(Ⅳ)

Spectrophotometric determination of titanium in steel with 4-(2-thiazolylazo)-1,2,3-trihydroxybenzene

在溴化十六烷基三甲基铵存在下，用分光光度法研究了4-（2-噻唑偶氮）连苯三酚与钛㈣的显色反应性能。结果表明：在pH2．0～5．0氯乙酸-氯乙酸钠缓冲溶液条件下，4-（2-噻唑偶氮）连苯三酚与钛㈣形成摩尔比为2：1的红色络合物，其最大吸收波长λmax为560nm，在25mL显色液中钛量在0～20μg范围内服从比尔定律，相关系数r=0．9990，测定的表观摩尔吸光系数ε560=4．07×10^4L·mol^-1·cm^-1，方法成功应用于钢样品中微量钛的测定，结果同认定值相符。

The chromogenic reaction of titanium（IV） with the reagent 4-（2-thiazolylazo）-1, 2, 3-trihydroxybenzene （TATB） has been studied spectrophotometrically in the presence of CTMAB in detail. The results show that in the medium of C1CH2COOH- C1CHzCOONa buffer solution at pH 2. 0 -5.0, Ti（Ⅳ） reacts with the reagent TATB to form a stable red complex with the molar ratio of n （Ti（Ⅳ））·n （TATB） = 1：2. The maximum absorption of the complex is at 560 nm with an apparent molar absorptivity of 4.07× 10^4 L·mol^-1· cm^-1. Beerrs law is obeyed in the range of 0-- 20μg/25 mL for Ti（1V） . The proposed method has been applied to the determination of titanium in steel samples, and the results are in agreement with the certified values.