A NEW METHOD FOR THE DETERMINATION OF DISSOLVED SULFIDE IN STRONGLY COLORED ANAEROBICALLY TREATED EFFLUENTS

A simple method for dissolved sulfide determination in colored complex media was developed using ion exchange chromatography. Its principle is based on the complete oxidation of an unstable compound (sulfide) i nto its stable form (sulfate) through a strong oxidant:hydrogen peroxi de. The difference between sample analyzed before and after this treat ment gives the total dissolved sulfide. In order to avoid H2S exhaust, this oxidation has to be performed immediately after sampling, withou t cell separation. In that way, standard solutions were prepared using raw anaerobic effluents from an industrial plant. It was shown in the calibration curve that no bacterial interaction was present. Finally, sulfide from continuous and discontinuous digestions of these sulfate rich wastewaters were successfully assayed by this technique. A theor etical evaluation based on Henry's law and the sulfide dissociation eq uilibrium led to a very good agreement with the analytical results.