Polyacrylic acid/carboxymethyl cellulose/activated carbon composite hydrogel for removal of heavy metal ion and cationic dye

For the purpose of purifying polluted water, polyacrylic acid grafted carboxymethyl cellulose and activated carbon composite material (PAA/CMC/AC) was used to efficiently and selectively capture heavy metal ions and dyes in polluted water. The maximum adsorption capacity of Cu2+ and methylene blue (MB) in the independent system reached 169 mg g(-1) and 119.9 mg g(-1), respectively. It is worth noting that in the case of coexistence of Cu2+ and MB, the adsorption of MB is hardly affected, while adsorption capacity of the adsorbent for Cu2+ increases with the increase of MB concentration in the presence of dyes, from 169 to 193.5 mg g(-1). For this, the adsorption isotherms and kinetics were fitted well by the Freundlich model and pseudo-second-order kinetic model. XPS results confirmed that surface complexation and electrostatic attraction are the main mechanisms of adsorption reaction. Finally, the regeneration performance of the adsorbent was explored.