高阶导数光度法同时测定原油和渣油中微量镍、钒、铁

在pH为3.0的邻苯二甲酸氢钾-盐酸缓冲溶液存在下,用5-Br-PADAP作显色剂,在水-乙醇介质中用高阶导数光度法同时测定了原油、渣油中微量镍、钒、铁。这种方法灵敏,选择性好,线性范围宽,省时。经过对不同产地的原油,渣油样品进行多次测定表明,这种方法的测定结果与原子吸收光谱法和等离子体直读光谱法的结果相吻合。相对标准偏差小于9％,回收率在90％～105％,符合测定要求。

THE SIMULTANEOUS DETERMINATION OF MICRO METALS IN CRUDE OIL AND RESIDUAL OIL WITH HIGH-ORDER DERIVATIVE SPECTROPHOTOMETRY

A new method for simultaneous determination of micro nickel,vanadium and iron in crude oil and residual oil with high-order derivative spectrophotometry is presented.5-Br-PADAP was taken as a chromogenic reagent in the buffer solution of 3.0 pH.A zero-crossing technique was used for determining nickel,iron and vanadium at 524 nm,604 nm and 620 nm with third ordcrand fourth order derivative spectrophotometry respectively.The standard deviation was less than 5.0 ppm,relative standard deviation less than 9% and the recovery rate is 90%-105%.The results were in good agreement with those obtained by AAS and ICP-AES.The method provides a satifactory result of precision and accuracy.