文档介绍：工业硫酸中砷含量测定影响因素探析
摘要:采用原子荧光光谱法测定工业硫酸中的砷含量,并对测定过程中可能影响实验准确度的因素进行了考察。实验结果表明,测定过程中体系酸度和金属离子对测定结果有一定影响,砷的荧光强度随着酸度增加而增大,当体系酸度在4%~10%时,测定结果相对稳定。在测量相对误差低于5%时,Cd、Fe、Zn、Pb等金属离子对砷的测定基本不产生干扰作用,而Cu和Ca离子则影响较大。
关键词:工业硫酸;原子荧光光谱法;砷;影响因素
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Study on the influential factors of the determination of arsenic in industrial sulfuric acid
Abstract: In this study, atomic fluorescence spectrometry was used for the determination of arsenic in industrial sulfuric acid. The influential factors that affect the experimental accuracy of the determination process were studied. The results showed that the system acidity and metal ions had some effect on the determination of arsenic. The fluorescence intensity of arsenic increased with increasing acidity, and the measured results were relatively stable when the system acidity was in the range of 4%~10%. When the relative measurement error was less than 5%, the transition-metal ions of Cd, Fe, Zn and Pb did not interfere the determination of arsenic, while Cu and Ca had greater impacts.
Keywords: Industrial sulfuric acid; Atomic fluorescence spectrometry; Arsenic; Influential factors
砷是工业硫酸中重要的控制指标之一[1]。工业硫酸中砷含量测定方法有二乙氨基二硫代甲酸银分光光度法(银盐法)、砷斑法、原子荧光法等。其中银盐法存在一定缺陷,比如检出限较高,灵敏度低,测定过程繁琐,且所使用的试剂毒性大,对人体和周围环境都有不利影响[2,3]。砷斑法测定砷含量的周期较长,操作过程烦琐,检验成本较高[4]。而利用原子荧光法测定砷含量由于准确度高、快速、抗干扰能力强、检出限低等优点,得到越来越广泛的应用[5-12]。实验中在利用直接称取样品稀释定容,采用原子荧光法测定工业硫酸中砷含量基础上,