摘要
目的:建立石墨消解仪-石墨炉原子吸收光谱测定土壤中的镉分析方法。方法:土壤样品用硝酸-氢氟酸-盐酸-高氯酸混合消解液在石墨消解仪中消解后,加入磷酸氢二铵、硝酸钯、硝酸镁、硝酸钯-硝酸镁混合基体改进剂消除干扰,用石墨炉原子吸收光谱测定。通过对基体改进剂、灰化温度、原子化温度的研究,优化了测定土壤中镉的条件。最终确定以0.2%硝酸钯为基体改进剂,样品进样为10μL,基体改进剂进样4μL,灰化温度分别为400℃和900℃,原子化温度为1900℃,净化温度为2600℃,氩气作保护气时进行土壤中镉测定的适宜条件。该方法线性良好,相关系数为0.9995,相对标准偏差3.46%和1.15%,方法检出限为0.012mg/kg。对土壤标样ESS-5和ESS-14的测定结果符合标准值要求。该方法简单,基体干扰少,结果准确,适用于土壤中镉含量的测定。
Objective:To establish a method to measure Cd in soil by graphite digestion system-graphite fumace atmic absorption spectrometry(GFAAS).Methods:The soil samples were digested in HNO 3-HF-HCl-HClO 4 solution under graphite digestion system;added diammonium phosphate、palladium nitrate、magnesium nitrate、palladium nitrate-magnesium nitrate mixed matrix modifier to eliminate interference and determined by GFAAS.Based on the study of matrix modifier,ashing temperature and atomization temperature,the conditions for the determination of cadmium in soil were optimized.It is ultimately determined that the 0.2%palladium nitrate as matrix modifier,the sample quantity 10μL,matrix modifier quantity 4μL,and ashing temperature at 400℃and 900℃,atomization temperature at 1900℃,purification temperature at 2600℃for the analysis under the protection of argon.The linearity of this method was good with a correlation of 0.9995 and the relative standard deviations were 3.46%and 1.15%,the detection limit is 0.012mg/kg.The determination results of ESS-5 and ESS-14 soil samples are within the standard value range.The method is characterized by simple and little disturbance with high accuracy;therefore,it is suitable for measurement of Cd in soil.
作者
刘文芳
Liu Weng-fang(Jiangxi Ji’an Ecological Environment Monitoring Center,Jiangxi Ji’an 343099)
出处
《江西化工》
2020年第3期106-111,共6页
Jiangxi Chemical Industry
关键词
土壤
镉
消解
基体改进剂
石墨炉原子吸收
Soil
Cd
digestion
matrix modifier
graphite fumace atomic absorption
