Determination of the Point of Zero Charge for Electrocoagulation Precipitates from an Iron Anode

This study determined the variation of current, temperature, pH, and amount of precipitate generated during an electrocoagulation process conducted using a pure iron electrode in 0.1 Na2SO4. Then, the points of zero charge of the hydroxide/oxyhydroxide precipitates thus produced were obtained by two different methods: a simplified mass potentiometic titration method and a salt titration method. The results from both methods yieldedpzc values of 3.6 ± 0.7. This signals the predominance of positively- charged surface groups. Users desiring the removal of specifically-charged water pollutants can use this information to adjust the pH values for such purposes.