Determination of selenium in geochemical samples such as drainage sediment
水系沉淀物等地球化学试样中硒的测定

摘要

硒是自然界中必然元素之一，在金矿成矿规律研究中是必测要素。在生物体中也含有微量硒，当硒含量超高时，便会对人体有害，同时硒存在于土壤和岩石中，但含量极低，只有6×10-7。硒在工业上的用途广泛，可以用来制作颜料、半导体以及一些电子器材。随着我国工业化进程逐渐加快，工业废水的排放，会导致农作物中硒的含量增多，对人的健康造成影响，因此对工业废水的硒含量测定具有重要意义[1]。其中最常见的是荧光分光光度法以及石墨炉原子吸收法。但是在实际检验中，由于硒含量不高，测定结果无法准确估计。为了有效测得样品中硒的含量，本文采取了氢化物—原子荧光法，并且进行了多种测量条件的研究，实验中利用抗坏血酸和硫脲还原硒提纯硒,在降低成本，提高效率的基础上，总结出了几点有效办法。

Abstract

Selenium is one of the inevitable elements in nature, which is required in the study of gold mineralization law.organisms also contain trace amounts of selenium, which is harmful to humans when it is extremely high. It is found in soil and rocks, but it is extremely low at 6x10-7. Selenium is widely used in industry, and can be used to make pigments, semiconductors, and some electronic equipment. With the gradual acceleration of China's industrialization process, the discharge of industrial wastewater will lead to the increase of selenium content in crops and affect people's health, so it is of great significance to the determination of selenium content of industrial wastewater. Among the most common [1] is fluorescence spectrophotometry and graphite furnace atomic absorption method. However, in the actual test, the measurement results could not be accurately estimated due to the low selenium content. In order to effectively measure the content of selenium in the sample, the hydride-atomic fluorescence method was adopted, and various measurement conditions were studied. In the experiment, ascorbic acid and thiourea were used to reduce selenium and purify selenium. On the basis of reducing the cost and improving the efficiency, several effective methods are summarized.