Porous Adsorbent Based on Kaolin and Nanomagnetic Cobalt Ferrite for Effective Removal of Pb(II) from Wastewater

Porous ceramic compound as adsorbents for heavy metal removal was produced by mixing kaolin with charcoal in addition to cobalt ferrite nanoparticles at 0, 3, 5, 7, and 10 wt%. The synthesized magnetic cobalt ferrites, prepared using sol-gel auto-combustion method, were characterized by X-ray diffraction, field emission scanning electron microscopy, and vibrating sample magnetometer, as well as examining the physical and mechanical characteristics of the kaolin/cobalt ferrite composite. PH and adsorbent dose were studied in the context of the adsorption of Pb2+, with a comparison of results against using crushed kaolin/CoFe2O4 powder. The resulting CoFe2O4 nanoparticles have saturation magnetization values of about 48.85 emu/g. Darcy permeability of the porous ceramics prepared by the semi-dry pressing method was increased from 1.9 to 4.6 cm/s; meanwhile, for porous ceramics prepared by the slip casting method, the permeability varied from 5 to 7.9 cm/s. Utilizing kaolin/CoFe2O4 particles, the best removal efficiency for Pb2 + was found to be 100% at pH 3 used 10 wt% of Co-ferrite for samples prepared by slip casting method and 91.9% for samples prepared by semi-dry method. In contrast, the best lead removal efficiency of 89.6% was reported at pH 5 when utilizing crushed kaolin/CoFe2O4 powder, and the removal efficiency increased at high concentrations of lead ions from 16.7 to 96.68%, with the highest adsorption of lead ions obtained at 50 min, reaching a removal efficiency of 83.23%.