基于ICP-AES的膨润土胶体浓度分析方法

Determination of the Concentration of Bentonite Colloid by ICP-AES

介绍了一种利用发射光谱测量胶体浓度的方法。研究了利用膨润土胶体的主要骨架元素定量胶体浓度的可行性和基于ICP-AES分析膨润土胶体浓度的方法。结果表明,采用HNO3-HF混合溶液浸泡的预处理方法可溶出绝大多数骨架元素;胶体含量与Si含量相关性较差,Mn的含量较低,不确定度大,而Fe和Al可作为膨润土胶体浓度检测的基准元素,其浓度与胶体浓度呈现良好的线性关系;样品的Fe/Al测量比值与荧光光谱分析法一致;加入内标元素Ni则显著提升了测量精度。

A noble method for determination of the bentonite colloid concentration was developed by using emission spectrum.HNO3/HF was employed for the digestion of bentonite colloid,and most of the framework elements,such as Al,Si,Fe and Mn,were able to be leached.Good linear correlations were found between the concentrations of Al(or Fe)and colloid,while the concentration of Si showed bad linear correlation with that of bentonite colloid.Therefore,Al and Fe were chosen as the reference elements for the determination of colloid.The measuring results obtained by ICP-AES are consistent with the measured values from XRF.Moreover,the addition of Ni as internal standard significantly improved the measurement precision.