Adsorption of Cr(VI) from wastewater by iron-modified coconut shell biochar

This study is aimed to investigate the effect of raw and Fe-modified coconut shell biochar on the adsorption of Cr(VI) in the wastewater. Fe-modified biochar was obtained from the impregnation with FeNO3 solutions and the surface functional groups of two biochars were examined by infrared spectrometer.The result showed that the Fe-modified biochar had lower abundance of the surface functional groups than that of raw biochar, and had the group of Fe-O.The removal rate of Cr(VI) increased by 94.89% compared with the raw biochar because of existing of the group of Fe-O . The removal rate of Cr(VI) by modified biochar could reach more than 99.0% when the concentration of Cr(VI) was 12μg/ mL, pH 4.0, adsorbent dosage was 0.2g and adsorption time was 2h