Identification of adsorption mechanism for Iron uptake by activated carbon derived from Alocasia indica

Abstract

The present study assess the potential of activated carbon derived from Alocasia indica, Taro, (ACT) for the removal of Fe(II) from the groundwater of Yaingangpokpi, Imphal East District, Manipur, India. The ground water was observed to be having Fe (II) concentration of 4.34 mg/L which is very much above the permissible limit of 1 mg/L. The adsorbent was activated using phosphoric acid and characterized by scanning electron microscopy (SEM) and energy dispersive X-ray measurements (EDAX). Adsorption kinetics study reveals that the kinetic data were better obeyed the Elovich kinetic model with correlation coefficient (R2) of 0.992 as compared to that of diffusion model with 0.93. Though, activated carbon are predominately physical adsorption due to the presence of large surface area, the study reveals a major chemical based adsorption due to the presence of functional groups in Alocasia indica (Taro). Adsorption isotherm studies reveals the adsorption was able to explained by both the non-linear Langmuir and Freundlich isotherm with insignificant error Chi square value of 0.05 and 0.003 respectively. The maximum adsorption capacity obtained was 4.03 mg Fe (II)/g ACT. These results proved that the adsorbent ACT is effective for the removal of Fe (II) from ground water.