ICP-AES Determination of Magnesium, Calcium, Aluminum, Iron, Manganese and Chloride in Light-Weight Partition Board

Ten grams of the sample were dissolved in 100 mL of 8 mol·L-1 HNO3. A definite amount of AgNO3 solution, 1.2 times as much as the equivalent amount (amount of substance) of Cl--ion estimated in the sample solution was added to form AgCl precipitate quantitatively. After aging, the mixture was filtered, and the filtrate was diluted to 200 mL in a volumetric flask. An aliquot of the solution was diluted 200 times, and macroamounts of Mg2+, Ca2+ and Ag+ ion (i.e. the excess of AgNO3 solution remained in the filtrate) were determined by ICP-AES. Amounts of chloride ion in the solution were calculated indirectly from the analytical results of Ag+-ion present in the solution. Another aliquot was taken from the filtrate in the volumetric flask and diluted 5 times, in which traces of Al(Ⅲ), Fe(Ⅲ) and Mn2+ were determined by ICP-AES. The proposed method was used in the determination of Mg2+, Ca2+, Cl- and Al(Ⅲ), Fe(Ⅲ), Mn2+ in a substantial sample, values of RSD′s (n=6) found were all less than 2%.