Synthesis of nano zero valent iron modified biochar for remediation of hexavalent chromium from water

Abstract

With the rapid industrialization, serious environmental concerns including wastewater pollution have been extensively reported over the globe. To meet effluent standards, various industries are focusing on environmental solutions utilizing green materials to keep environmental health safe. Amongst, food waste derived biochar material has received increased attention to remediate pollutants including heavy metals and organics from wastewater. Among various industries, tanneries are responsible for discharge of their effluents having large amount of chromium ions into water bodies. In lieu, current research focuses on a series of sorption experiments with focus towards remediation of Cr (VI) species with aid of orange peel powder biochar (BC) and nanoparticles of iron with zero valency modified carbon-based material called as biochar for example nZVI@BC. The outcomes indicated that nZVI@BC showed better Cr (VI) sorption performance than BC due to greater effective surface area, small particle size and uneven particle distribution. Current study also assesses different nZVI@BC modification ratios to examine Cr (VI) removal performance. It was noticed that nZVI@BC (1:3) shows greater removing ability of chromium (94.1%) instead of using nZVI@BC composites for starting amount of chromium in solution at 20mg/liter with water chemistry parameters adjusted at pH (2), standard temperature with amount of adsorbent (4 gram/Liter) and reaction proceeds for 120 minutes. The two-adsorption model as Freundlich adsorption model and pseudo second order adsorption model showed better results as compared to sorption results obtained from experiments. The XRD analysis along with FT-IR further confirmed the complexation reactions with additional reduction pathway as major sorption mechanisms in case of nZVI@BC. In general, current research may provide economic solutions to the tannery industry to remediate Cr (VI) from polluted water using nZVI@BC, thereby reducing its associated environmental health and ecological risks.