Removal of phosphates using eggshells and calcined eggshells in high phosphate solutions

Abstract This study was conducted to evaluate the phosphate sorption properties of eggshell (ES) and calcined ESs (C-ESs) in a high-concentration solution. The C-ESs yield decreased rapidly at 900 °C, indicating that CaCO 3 constituting ES converted CaO by high calcination temperature. optimum temperature for removal using C-ES °C. actual amount C-ES900 agreement with Langmuir isothermal equation, maximum capacities derived from this equation were 178.6 270.3 mg/g, respectively. rate divided into two stages: an initial fast stage, followed slow stage. dominantly influenced pH salt concentration, whereas exhibited constant capacity regardless environmental changes. SEM–EDS XRD results demonstrated successfully adsorbed on C-SE900 surfaces. In study, it found occurred via ion exchange precipitation reactions affected precipitation. Above all, can be applied as effective adsorbent removing concentrations under wide range conditions.