Alternative indirect method for sulfate determination in natural samples

Keeping in mind the determination of sulfate in natural samples like sea water and industrial effluents, a new indirect method for the determination of sulfate is proposed. It is based on the precipitation of sulfate as lead sulfate. The precipitate is dissolved in excess of ammoniacal solution of standard EDTA and the excess of this solution is determined by titration with magnesium standard solution using an indicator-mixture. A −0.56% relative error was found to a 12 mg level of sulfate mass. A study of the interference by several ions was also carried out.