Adsorption and removal of Cu (II) ions from aqueous solution using pretreated fish bones

Pretreated fish bones obtained from engraulis European anchovy ( Engraulis encrasicolus), European anchovy ( Sardine pilchardus), bogue ( Boops boops), bluefish ( Pomatomus saltatrix) and gilthead seabream ( Sparus aurata) were used as natural, cost-effective, waste sorbents for the adsorption and removal of copper from aqueous systems. The removal efficiency of the adsorbent was investigated as a function of pH, contact time, initial metal concentration, temperature, cleaning process, fish species and adsorbent dose. The maximum adsorption capacity was 150.7 mg/g at optimum conditions. The kinetic results of adsorption obeyed a pseudo-second-order model. Copper adsorption fitted the Langmuir isotherm. Δ H 0 value was 12.9 kJ/mol indicating that the adsorption mechanism was endothermic. The activation energy, E a , was determined as 52.9 kJ/mol. Weber–Morris and Urano–Tachikawa diffusion models were also applied to experimental equilibrium data. The fish bones were effectively used as a sorbent for the removal of Cu ions from aqueous solution.