火焰原子吸收分光光度法测量拜耳法赤泥中钠

Determination of sodium in Bayer red mud by flame atomic absorption spectrophotometry

赤泥是氧化铝生产过程中产生的强碱性固体残渣,强碱性限制了其在水泥等领域的大宗应用,亟待开发赤泥高效脱碱技术和配套的钠含量分析检测技术。本文采用火焰原子吸收分光光度法测量拜耳法赤泥中钠,对现有方法进行了改进,选用盐酸(1+1)消解赤泥样品,无需使用贵金属坩埚,优化了样品消解时间,并采用KCl有效消除了钠元素的电离干扰,纠正了文献中KCl的有效浓度范围。在优化测量条件下,加标回收率在99.17%-105.00%,赤泥标准样品测量相对误差在-0.22%-0.29%;赤泥原样测量相对标准偏差RSD(n=10)为1.28%,赤泥标准样品测量相对标准偏差RSD(n=3)为0.85%-2.72%。该方法灵敏度高、准确度和精密度好,常规实验室均可满足分析检测条件,可为赤泥高效脱碱和综合利用技术的开发提供可靠的分析检测支撑。

Red mud is a strong alkaline solid residue produced in the process of alumina production,which limits its large-scale application in cement and other fields.It is urgent to develop efficient alkali removal technology of red mud and support sodium content analysis and detection technology.In this paper,sodium in Bayer red mud was measured by flame atomic absorption spectrophotometry.The existing method was improved.The red mud sample was digested by hydrochloric acid(1+1)without using precious metal crucible.The digestion time of the sample was optimized.The ionization interference of sodium was effectively eliminated by KCl,and the effective concentration range of KCl in the literature was corrected.Under the optimized measurement conditions,the recovery rate of standard addition was 99.17%-105.00%,and the relative error of red mud standard sample was-0.22%-0.29%.The relative standard deviation(n=10)of red mud was 1.28%,and the relative standard deviation(n=3)of red mud standard sample was 0.85%-2.72%.The method has high sensitivity,good accuracy and precision,and the conventional laboratory can meet the analysis and detection conditions,which can provide reliable analysis and detection support for the development of effcient alkali removal and comprehensive utilization technology of red mud.