摘要
通常采用原子吸收分光光度计测定土壤中交换性钙、镁,采用火焰光度计测定土壤中交换性钾、钠,该方法的缺点是四种元素需要采用两种仪器共进行四次测定,分析流程较长,不能满足批量样品快速分析的需要。为了适应大批量样品分析,实验通过对石灰性土壤交换性钾、钠、钙、镁的前处理流程进行优化,用离心法代替淋洗法,先用70%乙醇溶液洗去土壤中水溶性的钾、钠、钙、镁,再用pH 8.5的0.1 mol/L氯化铵-70%乙醇溶液交换出土壤胶体吸附的钾、钠、钙、镁,并将交换液进行稀释,从而建立了电感耦合等离子体发射光谱法测定石灰性土壤中的交换性钾、钠、钙、镁的分析方法。在选定的测定条件下,各组分校准曲线线性相关系数均大于0.999,检出限为0.0073~0.0314 cmol/kg。按照实验方法测定土壤有效态一级标准物质GBW07493、ASA-2b-CZ、ASA-3b-CZ中交换性钾、钠、钙、镁,结果与认定值的相对误差(RE)为-1.48%~4.30%,相对标准偏差(RSD,n=6)为0.60%~3.07%,满足《生态地球化学评价样品分析技术要求(试行)》(DD2005-03)的分析质量要求。方法操作简便,成本低廉,适合大批量土壤样品分析。
Exchangeable calcium and magnesium in soil are usually determined by atomic absorption spectrophotometer and exchangeable potassium and sodium in soil are determined by flame photometer.However,it has some disadvantages such as the four elements need to be measured by two instruments for four times,and the analysis process is long,which cannot meet the needs of rapid analysis of samples in large quantities.In order to adapt to the analysis of large quantities of samples,the pretreatment process of exchangeable potassium,sodium,calcium and magnesium in calcareous soil was optimized,the leaching method was replaced by centrifugal method.The water-soluble potassium,sodium,calcium and magnesium in the soil were washed with 70%ethanol solution first,then the potassium,sodium,calcium and magnesium adsorbed by soil colloid were exchanged with 0.1 mol/L ammonium chloride-70%ethanol solution of pH 8.5,and the exchange solution was diluted.Thus,an analytical method for the determination of exchangeable potassium,sodium,calcium and magnesium in calcareous soil by inductively coupled plasma emission spectrometry was established.Under the selected testing conditions,the linear correlation coefficients of calibration curves of elements were all greater than 0.999.The detection limit of method were between 0.0073 cmol/kg and 0.0314 cmol/kg.The content of exchangable potassium,sodium,calcium and magnesium in primary reference materials of available state of soil(including GBW07493,ASA-2b-CZ and ASA-3b-CZ)were determined according to the experimental method.The relative error(RE)between found results and certified values were between-1.48%and 4.30%,and the relative standard deviation(RSD,n=6)were between 0.60%and 3.07%,which could meet the analysis quality requirements of“technical requirements for analysis of samples for ecological geochemistry assessment(trial implementation)”(DD2005-03).The method is simple,low cost and suitable for analysis of samples in large quantities.
作者
申硕果
赵一星
辛涛
吴林海
钟盼
刘春霞
张兰
杜华涛
SHEN Shuo-guo;ZHAO Yi-xing;XIN Tao;WU Lin-hai;ZHONG Pan;LIU Chun-xia;ZHANG Lan;DU Hua-tao(Geological Disaster Preventing and Controlling Center of Henan Provincial Bureau of Geology,Henan Zhengzhou 450012;The first Geological Exploration Institute Henan Bureau of Geology and Mineral Resources,Henan Zhengzhou 450000,China)
出处
《广州化工》
CAS
2023年第3期129-132,共4页
GuangZhou Chemical Industry
基金
河南省黄河中下游污染耕地生态环境监测关键技术研究与应用。
关键词
电感耦合等离子体发射光谱法
石灰性土壤
交换性钾、钠、钙、镁
离心法
inductively coupled plasma emission spectrometry
calcareous soil
exchangeable potassium,sodium,calcium and magnesium
centrifugal method
