Removal of arsenic(V) from aqueous solution by quaternized rice husk

The potential of using quaternized rice husk (QRH) as a sorbent for the rem oval of As(V) from aqueous solution was investigated. Both batch and column studies were carried out. Results of batch studies indicate that sorption was pH and temperature dependent. Equilibrium was attained within 20 minute s and sorption appeared to be essentially an ion exchange process. Experime ntal data could be fitted into the Langmuir isotherm with a maximum sorptio n capacity of 18.98 mg g(-1) at pH 7.5 and 28+/-2 degrees C. Anions such as SO42- and CrO42- interfere with the uptake of As(V) by QRH. In the column studies, results show that breakthrough depends on bed depth but not on flo w rate as sorption was very rapid. In addition, service time at 50% breakth rough was inversely proportional to influent concentration and had a linear relationship with bed-depth.