高效液相色谱-原子荧光光谱法测定土壤中4种有效砷形态  

Determination of Four Arsenic Species in Soils by High Performance Liquid Chromatography-Atomic Fluorescence Spectrometry

作　　者：范俊楠 田文娟 张钰 贺小敏 严文佩 张蒙 梁龙飞 FAN Junnan;TIAN Wenjuan;ZHANG Yu;HE Xiaomin;YAN Wenpei;ZHANG Meng;LIANG Longfei(Hubei Ecological Environmental Monitoring Center Station,Wuhan 430072;Hubei Institute of Measurement and Testing Technology,Wuhan 430223;Geophysical Exploration Brigade of Hubei Geological Bureau,Wuhan 430056)

机构地区：[1]湖北省生态环境监测中心站,湖北武汉430072 [2]湖北省计量测试技术研究院,湖北武汉430223 [3]湖北省地质局地球物理勘探大队,湖北武汉430056

出　　处：《分析科学学报》2022年第2期185-190,共6页Journal of Analytical Science

基　　金：国家环保公益性科研项目(No.201509031);2017年土壤污染防治湖北土壤污染风险评估与成因研究项目。

摘　　要：建立高效液相色谱-原子荧光光谱法(HPLC-AFS)测定土壤中亚砷酸根、二甲基砷、一甲基砷、砷酸根4种有效砷形态的分析检测方法。通过实验对提取液及浓度、流动相及pH值、载流HCl和还原剂KBH_(4)溶液等条件进行优化。方法采用不同pH值的KH_(2)PO_(4)溶液为提取液对不同酸碱度的土壤样品进行浸提,以Hamilton PRP-X100阴离子交换柱为色谱柱,1.725 g/L的(NH_(4))_(2)HPO_(4)溶液(pH=6.0±0.2)为流动相,20 g/L的KBH_(4)和5 g/L的KOH的混合溶液为还原剂,7%HCl溶液为载流。亚砷酸根、二甲基砷、一甲基砷、砷酸根在20 min内可完全分离,校准曲线线性相关系数(r)均大于0.9990;方法检出限分别为0.05 mg/kg、0.07 mg/kg、0.1 mg/kg、0.2 mg/kg;相对标准偏差范围为1.8%~17.2%,加标回收率范围为62.7%~1070%。本方法能够快速、简便、准确的测定土壤样品中上述4种有效砷形态。A method was developed for the determination of four arsenic species including arsenite,dimethylarsenic acid,monomethylarsenic acid and arsenate in soil by high performance liquid chromatography-atomic fluorescence spectrometry.The extraction solution and its concentration,mobile phase and pH value,concentration of hydrochloric acid and potassium borohydride were optimized.The potassium dihydrogen phosphate solutions with different pH values were used to extract four arsenic species form the soil samples with different acidity or alkalinity,and a Hamilton PRP-X100 reversed-phase anion exchange column was used for separation.The(NH_(4))_(2)HPO_(4) with 1.725 g/L(pH = 6.0±0.2) was used as the mobile phase.The mixture solution of potassium borohydride with 20 g/L and potassium hydroxide with 5 g/L were used for the reducing agents.The hydrochloric acid solution with volume fraction of 7% was used carrier.The four arsenic species can be separated completely within 20 min,and the linear correlation coefficients of the calibration curves were all over 0.9990.The detection limits were 0.05 mg/kg,0.07 mg/kg,0.1 mg/kg and 0.2 mg/kg,respectively.The range of relative standard deviation was about 1.8%-17.2% in laboratory,and the range of standard recovery was about 62.7%-107%.The developed method is rapid,simple,acurate and applicable for the determination of four arsenic species in soils.

关 键 词：高效液相色谱 原子荧光光谱 土壤 有效砷 形态检测 

分 类 号：O657.31[理学—分析化学]