【摘要】 水溶性试剂N-间甲苯基-N’-(对氨基苯磺酸钠)硫脲(MMPT)在HAc-NaAc缓冲介质和CTMAB(溴化十六烷基三甲胺)存在下,与铂(Ⅳ)和钯(Ⅱ)反应形成绿色和褐色水溶性络合物,其最大吸收波长分别为754.4和304.6nm。符合比尔定律的浓度范围分别为0～32μg.(25mL)-1,0～25μg.25(mL)-1,摩尔吸光系数为ε7P5t4.4=8.6×104L.mol-1.cm-1和ε3P0d4.6=7.4×104L.mol-1.cm-1。在754.4和304.6nm波长测定铂,钯混合液的吸光度,换算出铂、钯的含量。50种共存离子中,仅有Cu2+和Co2+对钯的测定有干扰。该法选择性好,用于合成样品、矿石和催化剂样品中铂、钯含量的测定,其相对标准偏差RSD小于2.0%;回收实验回收率是96%～104%。由于试剂铂、钯形成的络合物都易溶于水、不需予先分离同时测定,操作简便,快速,且环境友好。更多还原

【Abstract】 The N-(m-methylphenyl)-N’-(sodium p-aminobenzenesulfonate)-thiourea(MMPT)was good reagent of water solubility.In the medium of an HAc-NaAc buffer solution and hexadecyltrimethylammonium bromide(CTMAB),MMPT can react with platinum(Ⅳ)and palladium(Ⅱ)to form green and brown soluble complex.The maximum absorbance of the complex was at λPtmax=754.4 nm and λPdmax=304.6 nm.Beer’s law was obeyed with the concentration in the range of 0-32.0 μg Pt(Ⅳ)/25 mL and 0-25.0 μg Pd(Ⅱ)/25 mL for platinum(Ⅳ)and palladium(Ⅱ)respectively.The correlated coefficient was r754.4=0.999 5 for platinum(Ⅳ);and r304.6=0.999 9 for palladium(Ⅱ).Their molar absorption coefficients were εPt754.4=8.6×104 L·mol-1·cm-1 and εPd304.6=7.4×104 L·mol-1·cm-1 respectively.The contents of platinum(Ⅳ)and palladium(Ⅱ)were converted by determination of the absorbency of mix solution of platinum(Ⅳ)and palladium(Ⅱ)at 754.4 and 304.6 nm.Only Cu2+ and Co2+ interfered with the determination of palladium(Ⅱ)among 50 coexistent ions,so the selectivity was good.It can be used for the determination of content of synthesis samples.The relative standard deviation(RSD)was less than 2.0%,and the recovery(%)was in the range of 96%-104%.The results are satisfactory.Because the reagent reacts with platinum(Ⅳ)and palladium(Ⅱ)to form water soluble complex and does not require pre-separation for simultaneous determination of platinum(Ⅳ)and palladium(Ⅱ),the method is easy to operate,rapid and environment-friendly.更多还原