摘要
盐湖沉积物中可溶性阴离子提取和测试方法对其实验结果至关重要,但不同的前处理提取和测试条件缺乏系统的对比和优化。通过对比水浴加热、超声提取、涡旋振荡三种前处理条件的提取效率,发现涡旋振荡离心的前处理方法回收率最佳,并进一步优化了水土比例、涡旋振荡离心方法的浸提时间和浸提次数。在离子色谱测试中发现以30 mmol/L KOH溶液作为淋洗液,流速1 mL/min,柱温30℃,电导检测器进行离子色谱分析效果最佳。最终建立了以涡旋振荡离心为前处理提取,离子色谱法测定盐湖沉积物中四种无机可溶性阴离子(F^(-)、Cl^(-)、SO_(4)^(2-)和NO_(3)^(-))的检测方法。结果表明,四种阴离子检出限≤0.026 mg/L,线性相关性良好R2≥0.998,加标回收率为80.0%~114%,精密度RSD为0.64%~1.3%,具有快速准确、灵敏度高、简单可靠等优点,通过对6份西藏地区盐湖表层沉积物样品进行分析,发现Cl_(-)和SO_(4)^(2-)是主要的阴离子成份,与湖泊盐度趋势基本符合。方法可适用于高盐度盐湖沉积物样品中无机阴离子的测定。
The extraction and determination of soluble anions in salt lake sediments are crucial to the experience of results,but there is a lack of systematic comparison and optimization of different extraction methods and determination conditions compared with water bath heating and ultrasonic extraction,the extraction efficiency of vortex oscilation exhibited better performance.The water and soil ratio,extraction time and extraction frequency were further optimized.It was found that 30 mmol/L KOH solution,1 mL/min flow rate,30℃column temperature,and conductivity detector for determination were the optimum conditions of the ion chromatography.A quantitative method for extraction and analysis of four inorganic soluble anions(fluorine,chloride,sulfate,and nitrate)by ion chromatography was established.It showed that the detection limit of four anions were below 0.026 mg/L,with correlation coefficients were above 0.998.The addition recoveries were in the range of 80.0%-114%,and RSD was in the range of 0.64%-1.3%.This method had advantages of high sensitivity,precision,and efficiency.The results showed that Cl^(-) and SO_(4)^(2-)were the main anions,which was consistent with the trend of lake salinity.As a result,this method can be applied to the determination of inorganic anions in high salinity salt lake sediment samples.
作者
陶泽榕
金苗
孟先强
沈幸
陈辉辉
TAO Zerong;JIN Miao;MENG Xianqiang;SHEN Xing;CHEN Huihui(Nanjing Institute of Geography&Limnology Chinese Academy of Sciences,Nanjing,Jiangsu 210023,China)
出处
《中国无机分析化学》
CAS
北大核心
2023年第6期623-629,共7页
Chinese Journal of Inorganic Analytical Chemistry
基金
国家自然科学基金资助项目(41907222)。
关键词
离子色谱
无机阴离子
盐湖沉积物
涡旋振荡
ion chromatography
inorganic anion
salt lake sediments
vortex oscillation
