An analytical method for simultaneous determination of 12 impurity elements including Mo,Cr,Zn,Pb,Ni,Mn,Fe,Cu,Ca,Al,Na and K in N-methyl-2-pyrrolidone (NMP) was established with inductively coupled plasma optical emission spectrometry (ICP-OES) .The NMP without decomposing was acidized with nitric acid and analyzed directly,avoiding the risk of error introducing during sample pretreatment .The load of plasma on organic solvent was decreased by optimizing the plasma parameters and ensuring the stability of plasma .The optimized and adopted nebulizer gas flow rate was 04 L·min-1 and RF power was 800W .The whole signals during the sample atomization or ionization have been obtained with axially viewed ICP-OES which increases the sensitivity and decrease the detection limits .The interferences of spectral lines and background were eliminated by selecting analysis spectral lines,removing the carbon by adding oxygen and background correction method .Furthermore,standard addition method was employed to overcome the matrix effect,counteracting the ionization interference of high concerned organic matrix to easily ionizable elements .The results showed that the correlation coefficients of the calibration curve were in the range of 0999 5～1000 0,the detection limits were in the range of 38～1064 ng·g-1,and the recoveries were in the range of 92.0％～108.0％ .The relative standard deviation (RSD,n=11) were larger than 4.8％ of the analytes .The method is simple without complex sample pretreatment .It is a fast analysis method with high accuracy which can satisfy completely the requirements of control analysis in mass production .This method can be applied to determine impurity elements in NMP products .%建立电感耦合等离子体发射光谱(ICP-OES)法测定N-甲基吡咯烷酮(NMP)中12种杂质元素(Mo,Cr,Zn,Pb,Ni,Mn,Fe,Cu,Ca,Al,Na,K)的分析方法.将NMP用硝酸酸化后直接进样分析,无需对样品进行消解,避免了样品前处理时引入误差的风险.通过优化等离子体工作参数,减轻了有机溶剂对等离子体的负载,确保了等离子体的稳定工作,优化后等离子体射频功率为1 350 W,载气流量为040 L·min-1.采用轴向观测方式获取样品原子化或离子化过程中的所有信号,降低了方法的检出限,提高了分析灵敏度.通过选择各元素合适分析谱线、采用附加氧气除积碳并结合背景校正技术消除了各类谱线及背景干扰,选用标准加入法校正了基体效应,抵消了高浓度有机基质对易电离元素产生的干扰.结果表明,标准工作曲线的线性相关系数在0999 5～1000 0之间,检出限在38～1064 ng·g-1范围内,各元素的回收率在92.0％～108.0％之间,11次测定的相对标准偏差(RSD)≤4.8％.方法操作简单,无需复杂的样品预处理,分析速度快,测定结果准确可靠,精密度高,完全满足大批量实际产品的分析要求.方法可应用于NMP产品中杂质元素的监测.
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