摘要
本文对铝-铬黑T-OP体系进行了研究,发现在pH6时形成紫红色配合物,配合物至少稳定一周。以试剂空白作参比在波长625与688mm处分别出现正负吸收峰,两峰之和在5—80/μg/100ml范围与铝量呈线性关系。铝与铬黑T的组成比为1:3,表观摩尔吸光系数为5.3×10~4。而铁的配合物在628和688mm处吸收值相等,基于此测定铝时可消除铁的干扰。本法重现性好,灵敏度适中,可作为硅酸盐矿物中测定铝的例行方法。
Against a reagent blank, the purple Al-EBT-OP complex at pH 6 exhibits maximal positive and negative absorption peaks at 625 nm and 688 nm respectively. The absorbance difference ΔA is proportional to Al concentration in the range 5-80μg/100ml, with an apparent molar absorptivity of 5.3×104. The molar ratio of Al to EBT is 1:3, and the complex is stable for at least a week. The aluminum signal is measured at 628 nm and 688 nm, to take advantage of the isoabsorptive behavior of Fe(III) complex at both wavelengths. This method has been applied to the determination of major aluminum in silicate rocks and minerals with satisfactory results. The standard deviation and relative stadard deviation for a sample containing 16. 44%Al2O3 are 0.149% and 0.91% respectively (n=18).
出处
《岩矿测试》
CAS
CSCD
北大核心
1989年第1期24-28,共5页
Rock and Mineral Analysis
