摘要
为实现固体废物中氟含量的准确测定,采用氢氧化钠熔融样品,建立了碱熔-自动进样离子色谱法测定土壤中氟的分析方法。对碱熔剂用量、碱熔温度和碱熔时间进行了条件实验,确定了适用于土壤样品的前处理方法,样品于镍坩埚内加入3.5 g分析纯NaOH于马弗炉中缓慢升温至370℃与样品混合充分,继续升温到600℃熔融25 min。热水溶解提取、静置澄清55 h后取上清液使用732型强酸性阳离子交换树脂柱交换10 min后待测,将试液使用离子色谱AS^(-1)9250*4 mm阴离子分析柱分离,选用20 mmol·L^(-1) KOH淋洗液,流速为1.0 mL·min^(-1),化学抑制电导检测器检测氟含量。用标准物质曲线法进行实验,结果表明:使用土壤和水系沉积物标准物质曲线法进行计算,可以有效提高数据的准确度和校正离子干扰。按照实验方法测定土壤和水系沉积物国家标准物质中氟含量,本方法相关系数r>0.999,检出限为1.0 mg·kg^(-1),结果的相对标准偏差RSD<3%、加标回收率介于91%~105%之间。本实验方法操作简单、快速、准确且灵敏,适合于大批量土壤中氟的测定。
In order to determine fluorine in solid waste accurately,a method for the determination of fluorine in soil by Ion Chromatography with alkali fusion and automatic sampling was developed by using sodium hydroxide melt samples.The amounts of alkali flux,alkali melting temperature and alkali melting time were tested,and the suitable pretreatment method for soil samples was determined,the samples were heated to 370°C in muffle furnace by adding 3.5 g pure NaOH to a nickel crucible and mixed with the samples,and then heated to 600℃for 25 minutes.The supernatant was extracted by hot water and left to be clarified for 55 hours.The supernatant was then ion-exchange resined on a 732 type strong acid positive column for 10 minutes.The sample was then separated by Ion Chromatography on an AS^(-1)9250*4 mm anion analytical column,20 mmol·L^(-1) KOH eluent with a flow rate of 1.0 mL·min^(-1) was used to determine the fluorine content.The results show ed that using the standard material curve method to calculate the soil and stream sediments can effectively improve the accuracy of data and correct ion interference.According to the experimental method,the fluorine content in the national standard material of soil and stream sediment was determined.The experimental results showed that the correlation coefficient of this method was r>0.999,and the detection limit was 1.0 mg·kg^(-1).The relative standard deviation of the results was RSD<3%,the recoveries were from 91%to 105%.Therefore,The method is simple,rapid,accurate,sensitive and suitable for the determination of fluorine in a large number of soils.
作者
王斌堂
乔浩
吕旭
邓长生
李鹏飞
马传亮
WANG Bintang;QIAO Hao;LYU Xu;DENG Changsheng;LI Pengfei;MA Chuanliang(Geology Party No.216,CNNC,Urumqi Xinjiang 830011,China)
出处
《世界核地质科学》
CAS
2022年第3期587-595,共9页
World Nuclear Geoscience
关键词
土壤
氟
碱熔法
离子色谱法
soil
fluorine
alkali fusion
Ion Chromatography
