Mercury Persulphate

Earlier work on the determination of total mercury in river sediments also include that of Iskander et al. [41], Iskander applied flameless atomic absorption to a sulphuric acid nitric acid digest of the sample following reduction with potassium permanganate, potassium persulphate and stannous chloride. A detection limit of one part in 109 is claimed for this somewhat laborious method. 

Jurka and Carter [50] have described an automated determination of down to O.lpg L 1 mercury in river sediment samples. This method is based on the automated procedure of El-Awady [51] for the determination of total mercury in waters and waste waters in which potassium persulphate and sulphuric acid were used to digest samples for analysis by the cold vapour technique. These workers proved that the use of potassium permanganate as an additional oxidizing agent was unnecessary. 

Turbidity (AgCl) caused by traces of chloride present during silver-catalysed persulphate oxidation is prevented by the addition of a little mercury(II) sulphate [a stable complex, HgCL, is formed in the presence of Hg(ll)]. The mechanism and the conditions of Mn(ll) oxidation by persulphate in the presence of Ag(I) ions have been studied [11]. 

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