A simultaneous removal of ammonium and turbidity via an adsorptive coagulation for drinking water treatment process.

The utilization of natural zeolite (NZ) as an adsorbent for NH removal was investigated. Three types of NZ (i.e., NZ01, NZ02, and NZ03) were characterized, and their NH adsorption process in aqueous solution was evaluated. The effect of pH towards NH adsorption showed that the NZ01 has the highest NH adsorption capacity compared with other natural zeolites used. The application of NZ01 for a simultaneous removal of NH and turbidity in synthetic NH-kaolin suspension by adsorptive coagulation process for treating drinking water was studied. The addition of NZ01 into the system increased the NH removal efficiency (η) from 11.64% without NZ01 to 41.86% with the addition of 0.2 g L of NZ01. The turbidity removal (η), however, was insignificantly affected since the η was already higher than 98.0% over all studied parameter's ranges. The thermodynamic and kinetic data analyses suggested that the removal of NH4 obeyed the Temkin isotherm model and pseudo-second-order kinetic model, respectively. Generally, the turbidity removal was due to the flocculation of destabilized solid particles by alum in the suspension system. The η in surface water was 29.31%, which is lower compared with the removal in the synthetic NH-kaolin suspension, but a high η (98.65%) was observed. It was found that the addition of the NZ01 could enhance the removal of NH as well as other pollutants in the surface water.