Modification of Cellulosic Fibers and Adsorption of Chromium (VI) Ion from Dilute Aqueous Solution

The removal of Cr (VI) from aqueous solution is paying more and more attention due to the higher concern of environmental influence of this ion. In this paper, the biodegradable cellulosic fibers were modified with the grafting reaction to introduce the amide groups onto the fibers. In the grafting reaction, the toluene diisocyanate was firstly grafted on the surface of natural fibers, and then the 3-Chloro-2-hydroxypropyltrimethylammonium chloride (HPTMAC), as a high efficiency trapping agent of Cr (VI), was introduced through the condensation reaction. The modified fibers was characterized by infrared spectroscopy (IR) and elemental analysis. The modified fibers were applied to adsorb chromium (VI) ion from aqueous solution. The adsorption capability of the modified fibers was evaluated under different pH, time and temperature. The optimal adsorption conditions were obtained. The results showed that the grafted fibers had high efficient adsorption of chromium (VI) ion.