Removal of Fe (II) in groundwater using rice husk-sourced biosorbent in continuous column adsorption

Abstract

Ferrous is one of the groundwater contaminants that negatively impacts health and the environment. The allowed ferrous content is < 1 ppm in water for daily use. Removal of Fe in groundwater by adsorption using low-cost bio-sorbent from rice husk has been conducted. The process was carried out in continuous mode using two types of rice husk-sourced adsorbents, one was only carbonated at 400 C and another was followed by a physical activation at 650 C. To study the effects of physical activation on the surface characteristics, both types of biosorbents were characterized by Scanning Electron Microscope and Fourier-transform infrared spectroscopy. The concentration of artificial sample before and after adsorption was evaluated using the Atomic Absorption Spectroscopy. From the results, the adsorption using physically activated sorbent had greater removal efficiency of 74.02% compared to that of without activation treatment, which was only 65.70%. In addition, the concentration of ferrous was successfully reduced to 1,029 and 0.779 ppm from the initial concentration of 3 ppm for the process using the adsorbent without and with activation, respectively. It can be concluded that the physically activated rice husk has the potential to be used for adsorption of Ferrous in continuous column.