表面活性剂增敏2,4-二氯苯基荧光酮分光光度法测定煤中的微量锗

A method for the determination of germanium in coal samples by spectrophotometry has been developed. The color reaction of germanium with 2, 4-dichlorophenylfluorone (2, 4-DClPF) in the presence of cetyltrimethylammonium bromide (CTMAB) has been studied. The results show that Ge(Ⅳ) reacts on 2, 4-DClPF and CTMAB to form a multicomponent complex in a 1.8-2.5 mol•L^(-1) H2SO4 medium. The complex has the maximum absorption wavelength at 516 nm and its apparent molar absorptivity e is 1.38×10 L•mo1^(-1)•cm^(-1). Beer's law is obeyed in the range of 0-12.5 µg•(25 mL)^(-1) for Ge(Ⅳ). The recovery of standard addition is 103%-106% and the relative standard deviation (RSD) is 1.1%-1.7%. This method has been applied to the determination of Ge(Ⅳ) in coal samples with satisfactory results.