[Adsorption behavior of anionic dyes onto magnetic chitosan derivatives]

Adsorption of acid red 1 (AR1) and xylenol orange (XO) onto magnetic quaternary chitosan particles were studied through the static adsorption method. The results showed that, the maximal adsorption capacities calculated by Langmuir equations were 781.55 mg x g(-1) for AR1, 537.40 mg x g(-1) for XO at pH 3.0 and 25 degrees C. The constant n obtained by Frendlich equations were 1.71 and 1.92 respectively, which reflected the favourable adsorption of the dyes onto CS/EPTAC/Fe3O4. Temkin equations showed that heterogeneous surface of adsorbent was the main adsorption point. The adsorption kinetics of two kinds of dyes followed the pseudo-second-order model, which indicated the process was mainly chemical adsorption. Compared with the powder activated carbon, CS/EPTAC/Fe3O4 showed advantages of excellent adsorption performance, rapid separation and easy regeneration.