摘要
采用三氯化六氨合钴震荡提取,分光光度计测定土壤阳离子交换量。考虑pH对实验结果的影响,加入浸提液前所有土壤样品加固体NaOH改变土壤pH为碱性后,再进行分析;当样品阳离子交换量结果过高时采用减少称样量作为高含量样品的测定手段。实验结果表明,优化后方法检出限为8 mmol/kg;用该方法测定不同阳离子含量的土壤标准样品,测定结果均在标准值范围内。对样品平行测定5次,测定结果的相对标准偏差为2.7%~4.9%。对该方法与乙酸铵交换法在准确度﹑精密度﹑实际样品分析等方面进行对比,结果表明两种方法均满足实验要求,但三氯化六氨合钴分光光度法在安全性﹑试剂耗材和分析效率方面更具优势,适用于大批量土壤样品中阳离子交换量的测定。
The cation in soil was exchanged by cobalt trichloride hexaammonia spectrophotometry,and the cation exchange capacity in soil was determined by spectrophotometer.As pH might effect the experimental results,all sample were added with solid NaOH before adding the extraction solution to change the soil pH to alkaline,what’s more,the sample weight might be reduced when determining high content samples.The experimental results showed that the detection limit of the optimized method was 8 mmol/kg.The soil standard samples with different cationic contents were determined by this method,and the results were all within the standard value range.The samples were determined in parallel for 5 times,and the relative standard deviation of the determination results was 2.7%–4.9%.Compared with ammonium acetate exchange method in terms of accuracy,precision and actual sample analysis,the results showed that both methods meet the experimental requirements,however,cobalt hexaammoniate trichloride spectrophotometry has more advantages in safety,reagent consumables and analysis efficiency,which is suitable for the determination of a large number of soil cation exchange samples.
作者
岳中慧
岳启建
龙寿坤
周俊骅
范鹏飞
桂婷婷
YUE Zhonghui;YUE Qijian;LONG Shoukun;ZHOU Junhua;FAN Pengfei;GUI Tingting(Changsha Uranium Geology Research Institute,Changsha 410000,China;Lianshui County Center for Disease Prevention and Control,Huaian 223400,China)
出处
《化学分析计量》
CAS
2022年第4期55-59,共5页
Chemical Analysis And Meterage
关键词
震荡浸提
三氯化六氨合钴
阳离子交换量
土壤
vibration extraction
hexaammonium cobalt trichloride
cation exchange capacity
soil
