微波消解-原子吸收光谱法测定汽油中的铁

采用微波方法消解汽油样品，将汽油样品置于密闭容器内，加入一定量的硝酸，放在微波消解系统内进行消解。用正交试验研究了压力、消解时间、微波功率和酸度对消解效果的影响，确定了微波消解的最佳工作参数。对铁元素的测定进行了背景吸收干扰及化学干扰影响的研究。建立了用微波消解．原子吸收光谱法测定汽油中铁的方法。研究结果显示：该法测定精度高，相对标准偏差（n=5）≤1．45％，加标回收率为96．3％～104．4％，具有取样量少、消解用酸量少、操作简单、减少环境污染等优点。

Determination of Iron in Gasoline by Means of Microwave Digestion AAS

For controllingiron emission fromgasoline and environmental protection,it is necessary to establish a fast ,si mple and pre-cise Fe analysis method . Therefore ,the means of Microwave Digestion Atomic Absorption Spectroscopy ( AAS) was proposed foranalysis of Fe in gasoline . Gasoline samples were digestedin a microwave digestion system. Nitric acid was added to the samplesin aclosed digestion vessel and then digested in a microwave oven. Subsequently ,the iron content in the gasoline was analyzed usingAtomic Absorption Spectroscopy (AAS) . Orthogonal design of 4 factors (temperature ,ti me , power and amount of nitric acid) at2 levels was applied for the opti mumparameters of microwave digestion. The influence of chemical interference and background ab-sorbance was investigated . As a result ,a si mple ,cost effective and environment friendly method , Microwave Digestion AAS,for thedetermination of ironin gasoline was obtained . The relative standard deviation (n=5) islower than 1 .45 %and the recovery of Fe(original plus addition) is 96 .3 %~104 .4 %.