以熔融萘作稀释剂,用3,4-二氨基苯甲酸测定Pt是一种有效的分光光度法。Pt与3,4-二氨基苯甲酸(DBA)在90℃生成蓝绿色的配合物,在pH 10.0～12.5范围内,配合物定量地被萃取进入熔融萘中。有机相溶解于无水CHCl_3中,在715nm处以试剂为空白测定其吸光度,在Pt浓度为(0.1～2.0)×10~(-6)mol/L范围内服从比耳定律。摩尔吸光系数和桑德尔灵敏度分别为1.2×10~6L/mol·cm和0.00041mg/cm~2。实验确定了操作条件,考察了各种干扰离子的影响,并测定了混合样品中的Pt含量。 To melt naphthalene as a diluent, with 3,4-diaminobenzoic acid determination of Pt is an effective spectrophotometry. Pt and 3,4-diaminobenzoic acid (DBA) formed a blue-green complex at 90 ° C and the complex was quantitatively extracted into molten naphthalene at a pH of 10.0 to 12.5. The organic phase was dissolved in anhydrous CHCl 3, and its absorbance was measured at 715 nm with reagent blank. Beer ’s law was obeyed at Pt concentration of (0.1 ~ 2.0) × 10 -6 mol / L. Molar absorption coefficient and Sander sensitivity were 1.2 × 10 ~ 6L / mol · cm and 0.00041mg / cm ~ 2, respectively. The experimental conditions were determined, the effects of various interfering ions were examined, and the Pt content in the mixed samples was determined.