Preparation of chitosan-titanium dioxide beads for phenol degradation

Abstract

In this research, three types of beads as alternative means for phenol treatment were developed. Titanium dioxide blended chitosan beads (chitosan-TiO2) and modified titanium dioxide (TiO2) grafted chitosan were synthesized through the use of chitosan as a recovery agent. In addition, TiO2 spheres were prepared which explotied chitosan as a binder. The adsorption-photodegradation of phenol in the presence of chitosan and various UV irradiated titanium dioxide (TiO2) catalysts was investigated. The results revealed that modified tiO2 grafted chitosan beasd showed the best ability to remove phenol. The effect of gluaraldehyde concentration and glutaraldehyde incubation time on the modification of TiO2 was investigated. An optimum condition was to use 3.75% of glutaraldehyde and incubated for 1 h. The degradation of phenol depended on several parameters such as the distance between UV lamp and surface of the solution, agitation of solution, modified TiO2 concentration that was grafted on chitosan beads, reaction temperature, light intensity and initial phenol concentration. The modified TiO2 grafted on chitosan beads at 1% (w/v) of modified TiO2 exhibited the best concentration for the degradation of phenol when compared with other concentrations. An increase of the distance between UV lamp and surface of the solution and initial phenol concentration showed a decrease of phenol photodegradation. On the other hand, when the reaction temperature and light intensity increased, the removal of phenol increased. Besides, the agitation of solution during the photodegradation process process had an effect on the enhancement of phenol degradation. The efficiency of modified TiO2 grafted chitosan beads at 1% (w/v) of modified TiO2 to degrade phenol was about 10% decrease when they were reused after 5 times.