新试剂N-庚基-N′-(对氨基苯磺酸钠)硫脲光度法测定微量钯(Ⅱ)的研究

Spectrophotometric Study of the Reaction Between Pd(Ⅱ) and the New Reagent N Heptyl N′ (sodium p Aminobenzenesulfonate) Thiourea(HPT)

研究了N-庚基-N′-(对氨基苯磺酸钠)硫脲(HPT)与钯(Ⅱ)的反应条件。结果表明:在pH4.8~5.8的HAc-NaAc介质中,并有溴化十六烷基三甲胺(CTMAB)存在下,试剂HPT与钯(Ⅱ)形成稳定的黄色配合物,其最大吸收波长为295.2nm,表观摩尔吸光系数为2.98×105L·mol-1·cm-1。钯(Ⅱ)浓度在0.04~0.28mg/L范围内符合比尔定律,相关系数r=0.9989。方法简便、快速、选择性好,用于催化剂、贫钯矿中微量钯的测定,结果满意。

The reaction of Pd(l)with a new reagent N-hepty!-N'-(sodiump-aminoben-zenesulfonate)thiourea(HPT)was studied by spectrophotometry.In the range of pH4.8~5.8,Pd(【〉forms a stable yellow complex with HPT in the presence of cety!trimethylammonium bromide(CTMAB).Its apparent molar absorptivity is 2.98x10L.mo!'.cm~'at the maxinum absorption wavelength 295.2nm.Beer's law is obeyed in the range of 0.04~0.28mg/L for Pd(l).This method has been used for the determina-tion of trace Pd(I>in ores and catalyst with satisfactory results.