X射线荧光光谱法测定农田底泥中8种元素  

Determination of eight elements in farmland sediment by X-ray fluorescence spectrometry

作　　者：王晨希 WANG Chenxi(Zhenjiang Environmental Monitoring Center of Jiangsu Province,Zhenjiang 212000,China)

机构地区：[1]江苏省镇江环境监测中心,江苏镇江212000

出　　处：《化学分析计量》2022年第2期40-44,共5页Chemical Analysis And Meterage

摘　　要：建立X射线荧光光谱法测定农田底泥样品中砷、铬、铜、锰、镍、铅、锌、铁8种元素含量的分析方法。以塑料环粉末压片法制样,选用50种土壤、水系沉积物标准物质拟合校准曲线,探讨各元素的测定条件。当待测样品与建立校准曲线的标准样品粒径均小于75 μm时,能够有效减少矿物效应和粒度效应的影响,从而提高检测准确度;各元素在各自的含量范围内与荧光强度具有良好的线性关系,相关系数均大于0.99,方法检出限为0.003~4.1 mg/kg,均低于国标要求。标准物质的测定结果与标准值基本一致,相对误差不大于5.9%;8种重金属元素测定结果的相对标准偏差均小于3.5%(n=6)。对该法与电感耦合等离子体发射光谱法进行比对测试,两者结果的相对偏差不大于6%。该方法能够满足农田底泥的监测要求。An analytical method for the determination of eight elements,such as As,Cr,Cu,Mn,Ni,Pd,Zn,Fe in farmland sediment samples by X-ray fluorescence spectrometry(XRF) was established.The samples were prepared by plastic ring powder tablet pressing method.50 soil and stream sediment reference materials were selected to fit the calibration curve,and the determination conditions of each element were discussed.When the particle size of the sample to be tested and the standard sample establishing the calibration curve was less than 75 μm,the influence of mineral effect and particle size effect were effectively reduce,and the detection accuracy could be improved;Each element had a good linear relationship with fluorescence intensity in their respective content range,the correlation coefficients were more than 0.99,and the detection limits of the method were 0.003–4.1 mg/kg,which were lower than the requirements of the national standard.The determination results of reference materials were basically consistent with the standard values,and the relative error was not more than 5.9%;The relative standard deviation of the determination results of eight elements was less than 3.5%(n=6).Compared with Inductively coupled plasma atomic emission spectrometry,the relative deviation between the two results was not more than 6%.This method can meet the monitoring requirements of farmland sediment.

关 键 词：X射线荧光光谱法 农田底泥 塑料环粉末压片法 砷 铬 铜 锰 镍 铅 锌 铁 

分 类 号：O657.3[理学—分析化学]