Spectrophotometric Determination of Magnesium in the pressence of Mixed Sufactants by p-Sulfophenylazo Chromotropic Acid
Liu Shuren; Xu Xingling (Department of Chemical Engineening, Xi' an Petroleum institute, Xi' an 710061 )
p-Sulfophenylazo chromotropic acid reacts with magnesium in the presence of mixed surfactants (CPB+OP) to form a water soluble blue chelate. The optimum pH for the reaction is in the range of 10. 1~ 11. 3. The apparent molar absorption coeffient is 1. 23× 105 L. mol ~1. cm -1. By the addition of TEA-mannitol as masking reagents, better selectiv ity is achieved, and the method proposed can be applied to the determination of magnesium in the aluminium alloy with satisfactory results.