N-对甲苯基-N'-(氨基对苯磺酸钠)硫脲的合成及与铂(Ⅳ)的显色反应

Synthesis of the N-(p-methylphenyl)-N' (sodium p-aminobenzene-sulfonate)thiorea and Its Color Reaction with Platinum (Ⅳ)

详细介绍了新试剂N-对甲苯基-N’-(氨基对苯磺酸钠)硫脲(PMPT)的合成.经过红外光谱、紫外光谱、核磁共振和元素分析等方法测试,确定了试剂的组成和结构.研究了试剂与铂(Ⅳ)的显色反应,建立了光度法测定微量铂(Ⅳ)的方法.在pH3.6～5.2的HAc-NaAc缓冲体系中,该试剂和铂(Ⅳ)-形成一种稳定的组成比为1:3的绿色水溶性络合物,其最大吸收峰位于756nm处,表观摩尔吸光系数为ε_(756)=1.14×10~5·L·mol^(-1)·cm^(-1).铂含量在4～336μg/L服从比尔定律,相关系数r=0.9997,近50种离子不干扰.将该法应用于矿石和催化剂中铂的测定,获得满意的结果.

The new reagent N-(p-methylphenyl )-N'-( sodium p-aminobenzenesulfonate ) thiourea (PMPT) was synthesized and characterized by elecental analysis, 1HNMR, IR and UV spectra. Thecolor reaction of PMPT with Pt(Ⅳ) has been studied. In HAc-NaAc buffer solution at pH 3.6 - 5.2, Pt(Ⅳ) reacts with PMPT to form a 1:3 stable soluble complex with an apparent molar absorptivity of e =1.14×105L·mol-1·cm-1 at 756 nm. Beer's law is obeyed in the range of 4-336Ug/L Pt(Ⅳ) , thecorrelation coefficient is 0.9997. More than 40 ions didn't interfere. This method has been applied satisfactorily to the determination of platinum in ore samples and catalyst.