土壤中氟的形态分析

Speciation Analysis of Fluorine in Soil Samples

以宁夏盐池地区高氟土壤为例,采用连续提取法对土壤样品中各形态氟进行提取,离子色谱法测定各形态氟的含量。根据研究目的及土壤特点将氟的形态划分为水溶态、离子交换态、可还原态、可氧化态及残渣态5种形态;对各种形态连续提取过程中使用的提取液进行了选择。采用建立的方法获得提取土壤中F-的检出限为0.76μg/g;方法精密度(RSD,n=7)各形态氟为水溶态氟11.3%,离子交换态氟13.5%,可还原态氟10.7%,可氧化态氟8.9%。

The five fluorine species including water soluble fluorine, ion exchangeable fluorine, reducible fluorine, oxidizable fluorine and residual fluorine, in fluorine-rich soils in Yanchi County, Ningxia municipality were studied by sequential extraction and ion chromatographic analysis. The extraction reagents and conditions used in the sequential extraction were discussed. The detection limit of the method for F^- by ion chromatography is 0.76μg/g with the precision （n = 7） of 11.3% RSD for water soluble fluorine, 13.5% RSD for ion exchangeable fluorine, 10.7% RSD for reducible fluorine and 8.9% RSD for oxidizable fluorine.