Possibility of Removal of phosphate from an enclosed sea area by iron and steel slag coated with iron hydroxide

Abstract

ABSTRACT：In this study, the iron and steel slag coated with iron hydroxide was investigated for adsorbing phosphate from seawater by field experiments on an enclosed sea area. From the results of field experiments, it was found that the ability for phosphate adsorption was mostly influenced by phosphate concentration and pH of seawater. The adsorbed amount of phosphate also decreased with increasing pH and decreasing phosphate concentration of seawater. Particularly, as the phosphate concentration of seawater was less than 0.01 mg/L and pH of seawater was more than 8, the adsorbed phosphate was desorbed from the iron and steel slag coated with iron hydroxide. The seawater quality on the field sea area was changed by hydrographic conditions.