Removal of phosphate from wastewater using fly ash/ferrihydrite composite adsorbent

Fly ash/ferrihydrite composite adsorbent was prepared with fly ash and iron nitrate as raw materials in this study. Apparent characteristic of adsorbent was studied by means of scan electronic microscope (SEM). The removal of phosphate from wastewater was evaluated using fly ash treated with alkali and fly ash/ferrihydrite composite adsorbent. Also,batch experiments for adsorption were performed and the data of adsorption equilibrium were obtained. The results from Langmuir and Freundlich model regression analysis showed that the pattern of adsorption of phosphate with fly ash treated by alkali matches the Langmuir model,and fly ash/ferrihydrite composite adsorbent matches the Freundlich model.