|XU Rong, SUN Juan, HU Xiao le.Research on the Interference of Iron and Aluminum Ions to the Detection of Water Soluble Fluoride in Soil[J].Environmental Monitoring and Forewarning,2018,10(3):21-24
|通过离子选择电极法测定Fe3+和Al3+不同含量的土壤样品中水溶性氟化物试验，研究Fe3+ 和Al3+对测定的干扰与消除方法，证实了在总离子强度调节缓冲溶液共存下，Fe3+和Al3+对土壤提取液中水溶性氟化物检测结果存在不同程度的负干扰。选择6种代表性土壤样品，在水溶性氟化物提取液中加入20mg/L的 Al3+和100 mg/L的 Fe3+做干扰试验，比较了分取不同体积土壤提取液对氟化物检测结果的影响，结果表明，对水溶性ρ（Fe3+）和ρ（Al3+）高的土壤样品，可选择减少提取液取样体积来消除干扰。选取的5种标准样品测试结果与标准值相符，干扰消除方法具有良好的适用性。
|关键词: 铁、铝离子 土壤水溶性氟化物 离子选择电极法 干扰
|Research on the Interference of Iron and Aluminum Ions to the Detection of Water Soluble Fluoride in Soil
XU Rong, SUN Juan, HU Xiaole
Nanjing Environmental Monitoring Center, Nanjing，Jiangsu 210013, China
|The interference and elimination methods of iron and aluminum ions were studied by experiments which were about the determination of water soluble fluoride by ion selective electrode method in soils that contain different levels of iron and aluminum ions. Under the coexistence of the total ion intensity regulation buffer solution, the negative interference of iron and aluminum ions in the detection of water soluble fluoride in soil extracts was confirmed by experiments. 20 mg/L aluminum ions and 100 mg/L iron ions were added to water soluble fluoride extract of the six representative soil samples selected for interference test. The effects of different volume of the soil extracts on fluoride test results were compared. The test results showed that the interference could be eliminated by reducing the sampling volume when the sample was accompanied by high content of water soluble iron and aluminum ions. The test results of the five kinds standard samples selected were all consistent with the standard values which proved that the interference elimination method had good applicability.
|Key words: Iron and aluminum ions Water soluble fluoride in soil Ion selective electrode method Interference