Abstract Porous spherical adsorbents based on natural biopolymers, pure and co‐doped with activated carbon (AC), were prepared via dropping cum non‐solvent‐induced phase separation from ionic liquid–based solution. Their adsorption properties toward different types of model pollutants were evaluated. Blending of cellulose with chitosan (cellulose/chitosan = 75/25 wt/wt) led to improved adsorption of Cu 2+ and methyl orange (MO). Co‐doping with AC (10 wt % with respect to the biopolymer) clearly improved adsorption of dyes and tetracycline (TC) but slightly reduced adsorption of Cu 2+ . From mixed pollutant solutions, it was observed that TC and methylene blue can be adsorbed without competing for the same adsorption sites, whereas Cu 2+ and MO slightly compete.
Wittmar et al. (Fri,) studied this question.