Abstract
In this study, biochar from palm oil shell waste was applied as supporting material for the immobilized iron and copper oxide to fabricate the magnetic adsorbent of Fe 3 O 4 -CuO/biochar. The characterization showed that metallic oxide Fe 3 O 4 and CuO are dispersed on the surface of biochar with high accessibility. BET surface area is 263 m 2 g -1 relating to a predominantly microporous structure. FTIR spectra showed that the bands at 615.27 and 590.15 cm -1 are assigned to Cu-O-C and Fe-O-C stretching vibration, respectively. The average crystallized size for Fe 3 O 4 -CuO/biochar is 25 nm related to nanoparticle size. The efficiency of the adsorbent was observed from the percentage removal of inorganic anions in an aqueous solution. The highest efficiency of the adsorption process is found in the removal of phosphate at different pH solutions and contact times. The adsorption isotherms are matched for Langmuir and Freundlich models except for the fluoride. The kinetic model shows that pseudo-second-order is more favorable for the removal of inorganic anions than pseudo-first-order. This result indicated that Fe 3 O 4 -CuO/biochar is a promising adsorbent and will be effectively used for the removal of anions from an aqueous solution.