Efficiency of chemically activated raw and calcined waste fish bone for Adsorption of Cd(II) and Pb(II) from polluted water

Abstract

Bone biochare is used widely as an adsorbent in water pollution control; because of its high surface area and pore volumes . This study is attempting to prepare a low cost adsorbent from waste fish bone by chemical activation, and uses it for the removal of Pb and Cd from polluted water. Two methods were used for preparation of fish bone adsorbents. The first method includes the chemical activation of waste fish bone using different chemical activators ( 0.001 M HNO3, 0.1 M NaOH, 0.5 % H2O2, and ethanol), while the second one includes calcination of waste fish bone after the chemical activation at 600oC. The synthesized fish bone adsorbents were characterized by electron microscopy (SEM), X-ray diffractometer (XRD), X-ray fluorescence (XRF), BET surface area, and Fourier transform infrared (FT-IR). The efficiency of the prepared adsorbents for removal of Pb and Cd were investigated as a function of contact time, solution pH, solution temperature, initial metal concentration, and adsorbent dose. Metal concentrations were measured by atomic absorption spectroscopy . The results reveal that activation of the waste fish bone by 0.1 M NaOH is the suitable for the higher adsorption of Pb and Cd than with the other activators. The maximum adsorption of Pb and Cd on the chemically prepared adsorbent were 99.74 and 99.35 % , respectively at optimum conditions. The results of kinetic adsorption obeyed a pseudo-second-order model. Freundlich and Langmuir isotherms were applied , and the adsorption was found to be fitted well with the Langmuir model. This study ended with the success for preparing an ecofriendly and low cost fish bone adsorbent from the waste fish bone, and used it for the removal of Pb and Cd from polluted water