大气颗粒物重金属元素消解方法的响应面优化

Optimization of Digestion Parameters for Heavy Metal in Atmospheric Particles Using Response Surface Methodology

运用Plackett-Burman法确定了影响滤膜颗粒物中重金属元素提取效果的显著因素,利用Box-Behnken试验设计法得出回归模型,通过Minitab软件进行响应面分析得到最优消解条件:HNO3-HF体积比3.6∶1、恒温温度184.8℃、恒温时间13.8 min。标准滤膜GBW(E)080212中元素Pb最大的预测浓度为63.3μg/L,验证试验测定值与回归方程预测值的相对误差为0.2%,与标准滤膜真实值的相对误差为-0.3%。预测值与验证试验平均值基本一致,模型能较好的反应消解的实际情况。

Plackett-Burman method was applied to determine the significant factors affecting the extraction efficiency of heavy metals in filter particulates,meanwhile,regression model was obtained by using Box-Behnken experimental design method.Response surface methodology was carried out by Minitab software to obtain the optimal digestion conditions:HNO 3-HF volume ratio of 3.6∶ 1,constant temperature of 184.8 ℃,with 13.8 min.The maximum predicted concentration of element Pb in standard filter membrane GBW(E)080212 was 63.3 μg/L.The relative error between verification test value and predicted value of regression equation was 0.2%,the relative error between the verification test value and the true values of standard filter membrane was -0.3%.The predicted value was basically consistent with the average value of the validation test,and the model could properly reflect the actual situation of the digestion.