A Study on Adsorption of Fe (II) Ion by Rice Husks Digested with Nitric Acid

The objective of this study is to produce activated carbon from rice husks for Fe(H) ion
adsorption. Rice husks were digested by nitric acid at different concentrations at ambient
temperature over a period of 4 - 12 hours. The adsorption uptake increased with the
increase of the nitric acid concentration and digestion time due to higher microporosity and
larger internal surface. The carbonization temperature was varied to 500°C and 700°C.
The optimum carbonization temperature was identified to be 700 °C. Using data supplied
by the Atomic Absorption Spectrometry, adsorption isotherms were structured. The
adsorption characteristics followed the Langmuir isotherms.