分散液液微萃取-原子荧光光度法测定大米中的汞  

Determination of Mercury in Rice with Dispersive Liquid-Liquid Microextraction and Atomic Fluorescence Spectrometry

作　　者：陆建平[1] 覃梦琳 布静龙 邓扬辉 童张法[1] LU Jian-ping QIN Meng-lin BU Jing-long DENG Yang-hui TONG Zhang-fa(Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology, College of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, Chin)

机构地区：[1]广西石化资源加工及过程强化技术重点实验室广西大学化学化工学院,广西南宁530004

出　　处：《光谱学与光谱分析》2017年第11期3606-3609,共4页Spectroscopy and Spectral Analysis

基　　金：广西大学大学生实验技能和科技创新能力训练基金项目(SYJN20130340);广西石化资源加工及过程强化技术重点实验室主任课题基金项目(2014K0010);国家自然科学基金项目(E080404)资助

摘　　要：硝酸-高氯酸(4∶1,V/V)混合酸消解样品。双硫腙为络合剂,乙醇为分散剂,四氯化碳为萃取剂,建立了分散液液微萃取-原子荧光光度法测定大米中的汞的方法。优化了原子荧光光度计工作参数和分散液液微萃取的最佳络合酸度、络合剂用量、萃取剂种类及用量等条件。实验表明,在最佳条件下,方法的线性范围为0.005~25μg·L^(-1),相关系数为0.996 6,检出限为0.003μg·L^(-1),相对标准偏差为3.84%,加标回收率为90%~120%。该方法灵敏度高,分析速度快,准确性高,能有效检测大米中的痕量汞。Rice samples were digested by a mixture of nitric and perchloric acids （4 ： 1,V/V ）.Dithizone was used to chelate mercury ion in the sample solution,and the mercury complex was dispersed in ethanol before being extracted into carbon tetra-chloride.Thus,a method of determining mercury in rice by dispersion liquid micro extraction-atomic fluorescence spectrometry was established.The operating parameters of the instrument and optimal experimental conditions of dispersive liquid-liquid mi-croextraction were optimized,including the best complex acidity,the amount of complexing agent,extraction solvent type,the amount of dispersant dosage,and the extraction time.Experiments showed that under optimal conditions,the linear range was 0.005～25 μg·L-1 and the correlation coefficient was 0.9966 with the detection limit of 0.003 μg·L-1 ,the relative standard deviation （RSD）of 3.84%,and the recovery 95%～105% .The method is proven to be a sensitive,rapid,and accurate,way which can detect effectively trace amounts of mercury in rice.

关 键 词：大米 原子荧光光谱法 分散液液微萃取 双硫腙 汞 

分 类 号：O657.3[理学—分析化学]