离子色谱-电导法检测白酒中氟化物

Determination of fluoride in Baijiu by ion chromatography conductance-method

建立用离子色谱-电导检测法测定白酒中氟化物的分析方法。试样经纯水稀释,依次过0.22μm微孔滤膜、Dionex OnGuard II RP小柱处理后进样检测,选用IonPac AS19阴离子交换分离柱,氢氧化钾淋洗液梯度洗脱,流速1.0 mL/min,以电导检测器检测。结果表明:氟离子在0.005~0.200 mg/L质量浓度范围内具有良好的线性关系,相关系数R2为0.9999;方法检出限为5.21μg/L;在0.01 mg/L、0.02 mg/L、0.10 mg/L三个添加浓度水平下,平均回收率为97.18%~99.54%。该方法线性范围广,准确性和精密度良好,操作较简便,结果满意,能满足日常检测要求。

A method for the determination of fluoride in Baijiu(Chinese liquor)was established by ion chromatography-conductance method.The samples were diluted by purified water and filtrated with 0.22μm membrane and Dionex OnGuard II RP column.IonPac AS19 anion exchange separation column was used for gradient elution with potassium hydroxide eluent at a flow rate of 1.0 ml/min,and the results were detected by conductivity detector.The results showed that the linear relation of fluoride was good in the range of 0.005-0.200 mg/L(correlation coefficient R2=0.9999).The detection limit was 5.21μg/L.At the concentration addition levels of 0.01 mg/L,0.02 mg/L and 0.10 mg/L,the average recovery rates were 97.18%-99.54%.The method had a wide linear range,good accuracy and precision,and the operation was simple with satisfactory results,which could meet the requirements of daily detection.