Phosphate removal from wastewaters by a naturally occurring, calcium-rich sepiolite

► Natural occurring sepiolite was evaluated the first time as a phosphate absorbent. ► Natural occurring sepiolite has high phosphorus sorption capacity (32 mg P/g). ► The adsorption of phosphate was highly pH dependent. ► Except F− and HCO3−, no anions had influence on phosphorus removal capacity. ► Phosphate removed was primarily as Ca8-P precipitation.