水和氯化铵提取-电感耦合等离子体原子发射光谱(ICP-AES)法测定石灰性土壤中的交换性钾钠钙镁

Determination of Exchangeable Potassium, Sodium, Calcium and Magnesium in Calcareous Soil by Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES) with Water and Ammonium Chloride Extraction

为了提高石灰性土壤中交换性钾钠钙镁的分析效率及分析准确度,采用水和氯化铵对石灰性土壤进行处理,并采用振荡交换、离心分离的方式进行石灰盐清洗、钾钠钙镁离子交换提取,提取液直接在电感耦合等离子体原子发射光谱仪(ICP-AES)上测定。交换性盐基钾钠钙镁的检出限分别为0.004、0.012、0.01、0.009 cmol/kg。用国家一级标准物质GBW07498中新疆棕漠土和新疆地区石灰性土壤进行验证,方法相对标准偏差均小于5%,加标回收率在97.0%~105%。方法适用于石灰性(碱性)土壤(特别是新疆土壤)样品中交换性钾钠钙镁的分析测定。

In order to improve the analysis efficiency and accuracy of exchangeable potassium, sodium, calcium and magnesium in calcareous soil, water and ammonium chloride were used innovatively to treat calcareous soil, and vibration exchange and centrifugal separation were used for lime salt cleaning, potassium-sodium-calcium-magnesium ion exchange extraction, and the extract was directly measured by inductively coupled plasma-atomic emission spectrometry(ICP-AES).The detection limits of exchangeable calcium, magnesium, potassium and sodium were 0.01,0.009,0.004 and 0.012 cmol/kg, respectively.Verification was carried out with brown desert soil and calcareous soil in Xinjiang mentioned in national standard reference materials GBW07498.The precision of the method was less than 5%,and the recovery rate was between 97.0% and 105%.The method is suitable for the analysis and determination of exchangeable potassium, sodium, calcium and magnesium in calcareous(alkaline) soil(especially soil in Xinjiang).