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

Abstract

Background: 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 (biochare) from the waste fish bone by chemical activation, and uses it for the removal of Pb and Cd from wastewater. Fish bone adsorbent was prepared by two methods, one by activation with different chemical activators include 0.001 M HNO3, 0.1 M NaOH, 0.5 % H2O2, and ethanol ( FB) . The other method by calcination after the chemical activation at 600oC (FB-Hy). The synthesized fish biochare 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 Pb and Cd were investigated as a function of contact time, pH,solution temperature, initial metal concentration, and adsorbent dose. Metal concentrations were determined by atomic absorption spectroscopy .Results: The results reveal that activation of the fish bone by 0.1 M NaOH is the suitable for the higher adsorption of Pb and Cd than with the other activators. The chemically treated bone adsorbent by 0.1 M NaOH (FB) shows higher removal of Pb and Cd than with that chemically calcinated adsorbent (FB-Hy). The maximum adsorption of Pb and Cd on the chemically prepared adsorbent(FB) 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 in which the adsorption fitted with the Langmuir isothermConclusion: 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