Determination of calcium content in chemical fertilizers by microwave digestion-ICP-OES method and microwave digestion-AAS method
New methods for the determination of calcium in chemical fertilizers by microwave digestion using ICP-OES and AAS were established.The results of the method in the national standard GB/T 19203-2003 and these two methods were studied by t-test.2 Compound fertilizer standard materials and 12 fertilizer samples containing different calcium contents were determined.The t-test results showed that there was no significant difference in the extraction results between the microwave digestion method and the nitric acid perchloric acid electric heating plate digestion method in GB/T 19203;there was no signifi-cant difference in the results among the AAS method,ICP-OES method,and the volumetric method in GB/T 19203.The precision of two instrumental methods are slightly superior to volumetric method.The precision,recovery rate,and standard curve determination coefficient of ICP-OES method are slightly bet-ter than AAS method.For microwave digestion-AAS method,the standard material recovery rate were 106.2％,106.4％,respectively,and the relative standard deviation of 6 parallel determinations was 1.63％.For microwave digestion-ICP-OES method,the standard material recovery rates were 104.6％,103.2％,respectively,and the relative standard deviation of 6 parallel determinations was 1.58％.
chemical fertilizercalcium contentmicrowave digestionICP-OESAAS
NETL
NSTL
万方数据
