Alkali modified corn cob hydrochar as biosorbent of Mn2+ ions from aqueous solutions

Abstract

In this study corn cob hydrochar was investigated as potential material for the biosorption process. The corn cob hydrochar obtained at different carbonization temperatures (180, 200 and 220°C) were examined as potential adsorbent of Mn2+ from aqueous solution. The adsorption capacity of corn cob hydrochar obtained at different carbonization temperatures followed the decreasing order: 220°C > 200°C > 180°C To enhance adsorption potential, hydrochar with best adsorption abilities obtained at 220°C (HC) was subjected to cold alkaline modification. The modified corn cob (M-HC) was prepared through a chemical treatment process using 2M KOH solution. Preliminary results showed that the M-HC exhibited excellent adsorption characteristics for Mn2+ removal from aqueous solution. The maximum adsorption capacity (qmax) of M-HC and HC was 31.83 and 7.83 mg/g, respectively. It can be concluded that modified corn cob hydrochar can be used as a lowcost, eco-friendly and promising adsorbent with a good adsorption capacity for Mn ions removal from aqueous solutions.