萃取/反萃取-电感耦合等离子体发射光谱(ICP-OES)法测定肥料样品中铅、镉、汞、铊、锑、砷  

Determination of Lead,Cadmium,Mercury,Thallium,Antimony,and Arsenic in Fertilizers by Inductively Coupled Plasma Optical Emission Spectrometry Combined with Extraction and Anti-extraction

作　　者：刘珂珂[1] 谢亚雄[1] 李果果 张祥 董学亮[1] LIU Keke;XIE Yaxiong;LI Guoguo;ZHANG Xiang;DONG Xueliang(High&New Technology Research Center of Henan Academy of Science,Zhengzhou,Henan 450002,China)

机构地区：[1]河南省科学院高新技术研究中心,郑州450002

出　　处：《中国无机分析化学》2024年第9期1248-1254,共7页Chinese Journal of Inorganic Analytical Chemistry

基　　金：河南省科技厅社会发展项目(222102320184);河南省科学院重大聚焦专项项目(220102002)。

摘　　要：为保障农产品的质量与安全,肥料中的有毒有害物质,尤其是重金属含量被严格限制。为提高肥料中有毒有害物质检测的效率,利用铅、镉、汞、铊、锑、砷在盐酸介质中形成稳定的碘络合物的特性,采用甲基异丁基酮(MIBK)萃取、硝酸溶液反萃取的方法实现肥料样品中基质与待测元素的分离,通过电感耦合等离子体发射光谱法测定肥料样品中的6种重金属元素。通过考察萃取条件及残余基体对分析结果的影响,结果证实,在6 mol/L的盐酸萃取体系中加入5 mL碘化铵(30%)溶液,采用10 mL的MIBK萃取2~3次即可使样品中的铅、镉、汞、铊、锑、砷等被完全萃取,通过萃取/反萃取的方法实现了样品的分离富集,方法的检出限(3σ)为铅0.042 mg/kg、镉0.005 mg/kg、汞0.059 mg/kg、铊0.026 mg/kg、锑0.024 mg/kg、砷0.052 mg/kg,加标回收率在90.1%~108%,可以满足不同肥料样品的质量控制要求。按照实验方法测定6种不同肥料样品中的重金属含量,并采用标准方法进行方法比对,结果表明两种方法的测定结果基本一致。The levels of toxic and noxious elements,especially heavy metals are strictly enforced in fertilizers in order to protect the quality and safety of agricultural products.In order to improve the efficiency of detecting toxic and harmful substances in fertilizers,a method was constructed for the determination of Pb,Cd,Hg,Tl,Sb and As in fertilizers by inductively coupled plasma optical emission spectrometry(ICP-OES),which was based on the principle that these metallic ions could form stable complexes with iodine ions in the medium of hydrochloric acid.These metallic-iodide systems could be extracted with 4-methyl-2-pentanone(MIBK)and then anti-extracted by nitric acid solution to achieve the purpose that these metallic ions could be separated from the sample matrix.The effects of extraction condition and remnant matrix elements were studied in detail.The results confirmed that the extraction condition was optimized with 6 mol/L HCl and 5 mL NH 4 I(30%)solution,then the obtained metallic-iodine complexes were extracted completely for 2—3 times with 10 mL MIBK.Owing to the extraction and anti-extraction process,metallic ions were concentrated.The detect limits(3σ)were 0.042 mg/kg for Pb,0.005 mg/kg for Cd,0.059 mg/kg for Hg,0.026 mg/kg for Tl,0.024 mg/kg for Sb and 0.052 mg/kg for As.Test for recovery was made by standard addition method,giving results in the range of 90.1%—108%,which could satisfy the quality control requirement for fertilizer samples.The contents of heavy metals in six different fertilizer samples were determined according to the experimental method,and the determination results had no remarkable differences with those obtained by national standard method.

关 键 词：肥料 电感耦合等离子体发射光谱法 萃取/反萃取 有毒有害物质 

分 类 号：O657.31[理学—分析化学]