Abstract The impact of raw-water pH value, polymeric-ferric-sulphate (PFS) dosage, coexisting anion (i.e., bicarbonate and phosphate ions), and humic acid (HA) was explored on antimony (V) removal effect from drinking water sources by enhanced coagulation with PFS (as flocculant). In addition, the action mechanisms of removal process were also discussed. The results showed that pH value of raw water significantly affects antimony (V) existing forms and PFS hydrolysates during enhanced coagulation, reflected by an increase of antimony (V) removal efficiency with reducing pH value or increasing PFS dosage. As a result of competitive adsorption, coexsiting anion and HA have a negative influence on the removal of antimony (V) by coagulation. Moreover, antimony (V) removal process by PFS coagulation has been found to be more in line with the pseudo-second-order kinetic model.
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Received: 08 May 2015
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