K. J. Somaiya

Abstract Nanoporous carbon (NPC) structures synthesized from grass clippings mown at yard were acid functionalized and coated with manganese oxide nanoparticles at room temperature. The synthesized composite was characterized by FTIR, XRD, BET, TEM, TGA and XPS. Characterization results showed formation of acid functionalized nanoporouscarbon/MnO2 (Af-NPC/MnO2) composite which was amorphous in nature. Af-NPC/MnO2 was further explored for removal of As(III) and As(V) from aqueous medium. Effects of factors such as pH, contact time, initial concentration and interfering ions on adsorption of arsenic by Af-NPC/MnO2 were studied in detail. The mechanism of adsorption was also studied using experimental data determined. The kinetic study indicated that removal of arsenic follow pseudo second order kinetics and the experimental equilibrium data fitted better in Langmuir isotherm model with maximum monolayer adsorption capacity of 8.85 mg/g and 9.43 mg/g for As(III) and As(V), respectively. The removal rate of arsenic was found to be very fast compared to other adsorbents. The results of this study imply that Af-NPC/MnO2 is an efficient adsorbent for removal of As(III) and As(V) from aqueous medium.