摘要
针对乙二胺四乙酸(EDTA)-乙酸铵交换法测定土壤阳离子交换量耗时长的问题,对方法的搅拌方式、搅拌时间、蒸馏时间进行优化。优化后分析条件为:用磁力搅拌器代替人工橡皮头玻璃棒搅拌,确定搅拌时间为90 s,确定蒸馏时间为6 min。选择4个不同地区不同阳离子交换量的土壤标准物质用优化前、后的方法分别进行7次测定,其检测结果相对标准偏差为1.53%~5.32%;28个实际样品进行成对二样本均值分析,优化前、优化后测定的土壤阳离子交换量结果无显著性差异;对优化前、后28个土壤样品阳离子交换量测定结果进行相关性分析,线性相关显著,相关系数r=0.998。结果表明,EDTA-乙酸铵交换法优化前、后均具有较好的精密度和准确度,结果无显著性差异,EDTA乙酸铵交换法优化后的方法检测时间(1人测定8个样品)由280 min缩短到130 min,提高了检测效率,适合批量石灰性土壤阳离子代换量的测定。
Aiming at the problem that the ethylenediamine tetraacetic acid(EDTA)-ammonium acetate exchange method takes a long time to determine the cation exchange capacity(CEC)of soil,the stirring mode,stirring time and distillation time of the method were optimized.After optimization,the analysis conditions were as follows:magnetic stirrer was used to instead of manual eraser glass rod for stirring,the stirring time was determined to be 90 s,and the distillation time was determined to be 6 min;Four soil reference materials with different CEC content in different areas were selected for 7 times by the method before and after optimization,and the relative standard deviations of the detection results were 1.53%-5.32%.The pairwise two-sample mean analysis of 28 actual samples showed that there was no significant difference between the results of soil cation exchange capacity measured before and after optimization.The correlation analysis of the cationic exchange capacity of 28 soil samples before and after optimization showed that the linear correlation was significant,and the correlation coefficient R=0.998.The results showed that the EDTA-ammonium acetate exchange method had good precision and accuracy before and after optimization,and there was no significant difference in the results.The detection time of the optimized EDTA-ammonium acetate exchange method(1 person to determine 8 samples)was shortened from 280 min to 130 min,which improved the detection efficiency and was suitable for the determination of cation substitution amount in calcaric soil in batches.
作者
王卓
郭全恩
曹诗瑜
展宗冰
WANG Zhuo;GUO Quanen;CAO Shiyu;ZHAN Zongbing(Institute of soil,fertilizer and water-saving agriculture,Gansu Academy of Agricultural Sciences,Lanzhou 730070,China;Gansu Academy of Agricultural Sciences,Lanzhou 730070)
出处
《化学分析计量》
CAS
2024年第2期87-92,共6页
Chemical Analysis And Meterage
基金
甘肃省科技厅重点研发计划(22YF7NA036)。
关键词
土壤
阳离子交换量
乙二胺四乙酸-乙酸铵交换法
磁力搅拌器
soil
cation exchange capacity
ethylenediamine tetraacetic acid-ammonium acetate exchange method
agnetic stirrer
