摘要
提出了碱熔-超声提取-离子色谱法测定土壤中总氟化物(以F-计)含量的方法。称取过筛后的土壤样品0.200 0 g于镍坩埚中,加入氢氧化钠2.00 g,用马弗炉以程序升温方式(以5℃·min^(-1)速率升温至300℃,保持10 min;再以5℃·min^(-1)速率升温至560℃,保持30 min)熔融样品。熔融结束后,将镍坩埚放入预先装有40 mL水的烧杯中,超声提取10 min,将提取液转移至100 mL比色管,用15 mL水清洗烧杯3次,清洗液转移至比色管中,缓慢加入50%(体积分数)盐酸溶液5.0 mL,再用水定容,静置15 min,所得溶液经0.45μm微孔滤膜过滤,滤液经DionexTMInGuardTMAg柱处理后采用离子色谱柱法测定其中总氟化物的含量。结果显示:F-质量浓度在5.00 mg·L^(-1)以内与其对应的峰面积呈线性关系,检出限为25 mg·kg^(-1);以土壤标准物质GBW 07408、GBW 07446、GBW 07447验证方法精密度和准确度,氟化物测定值的相对标准偏差(n=6)为1.1%~2.8%,相对误差为-0.87%~2.7%;方法用于分析3个实际土壤样品,氟化物的测定值分别为309,927,636 mg·kg^(-1),与离子选择电极法所得测定结果基本一致。
A method for the determination of total fluoride(F-) in soil by ion chromatography after alkali fusion and ultrasound extraction was proposed. The sieved soil sample(0.200 0 g) was placed into nickel crucible, and 2.00 g of sodium hydroxide was added. The sample was fused by muffle furnace with programmed heating(the temperature was heated at 5 ℃·min^(-1)to 300 ℃, keeping for 10 min at 300 ℃, and then heated at 5 ℃·min^(-1)to 560 ℃, keeping for 30 min at 560 ℃). After fusion, the nickel crucible was placed into beaker pre-loaded 40 mL of water, and ultrasonic extraction was performed for 10 min. Then the extraction solution was transferred to a 100 mL-colorimetric tube, and the beaker was washed 3 times with 15 mL of water. The cleaning solution was transferred to the above colorimetric tube, and 5.0 mL of 50%(volume fraction) hydrochloric acid solution was slowly added, and then its volume was filled with water, settling for 15 min. The obtained solution was filtered by 0.45 μm microporous filter membrane, and the filtrate was processed by DionexTMInGuardTMAg column for determination of total fluoride by ion chromatography. As shown by the results, linear relationship between the values of mass concentration and its corresponding peak area of F-was kept within 5.00 mg·L^(-1), with detection limit of 25 mg·kg^(-1). The soil reference materials GBW 07408, GBW 07446 and GBW 07447 were used for verification of precision and accuracy of this method, and RSDs(n=6) of the determined values of fluoride were in the range of 1.1%-2.8%, and the relative errors ranged from-0.87% to 2.7%. This method was applied to analysis of 3 actual soil samples, and the determined values of fluoride were 309, 927, 636 mg·kg^(-1), respectively, which were basically consisten with those obtained by the ion selective electrode method.
作者
张晨芳
刘献锋
李墨
龚亮
胡霜
苏海涛
钱亮
胡建
ZHANG Chenfang;LIU Xianfeng;LI Mo;GONG Liang;HU Shuang;SU Haitao;QIAN Liang;HU Jian(Institute of Geochemical Exploration and Marine Geological Survey East China Mineral Exploration and Development Bureau,Nanjing 210007,China;Key Laboratory of Coastal Salt Marsh Ecosystems and Resources,Ministry of Natural Resources,Nanjing 211135,China;College of Environment Engineer,Institute Technology of Nanjing,Nanjing 211167,China)
出处
《理化检验（化学分册）》
CAS
CSCD
北大核心
2023年第1期93-97,共5页
Physical Testing and Chemical Analysis(Part B:Chemical Analysis)
基金
长江经济带(南通段)沿江地区多要素生态地质环境综合调查与评价项目(苏财资环[2019]14号)。
关键词
氟化物
超声提取
土壤
离子色谱法
fluoride
ultrasonic extraction
soil
ion chromatography
