Determination of Potassium and Calcium in Beans and Rices by Suspension Sampling Flame Atomic Emission Spectrometry

The suspension sampling technique was applied to flame atomic emission spectrometry to determine successfully potassium and calcium in red bean,green bean,rice,millet and sorghum.An analytical method for the rapid determination of potassium and calcium in beans and rice was developed.The selection of suspension agents,elimination of inter ference,the linear range and the detection limit were studied.The samples were ground down and made into agar suspension for rice or agar dibutyl phthalate suspension for beans.The test solutions were prepared by adding releasing agent La(Ⅲ) or deionization agent NaCl solution and proper amount of agar solution to appropriate amount of the suspension .The determination results were consistent with those obtained by ashing method-flame atomic absorption spectrometry.The relative errors between the two methods were less than±4.0%.The T test showed that no difference was found between the results obtained from these two methods.RSD was less than 3.3%. The detection limits obtained from 3σ/S were respec tively 0.012 for potassium and 0.041mg/L for calcium.This method is convenient,rapid and accurate.