Characterization and evaluation of the adsorption potential of chitosan-impregnated cellulose nanofiber multi-walled carbon nanotube aerogel for copper ions

Abstract

The development of aerogel materials with high preparation efficiency, no pollution, and high adsorption efficiency is still an effective solution for water pollution caused by heavy metal ions. We propose a simple and efficient way to prepare composite aerogel with a porous network-like structure to adsorb copper ions. The new adsorbent (CTC) was prepared by impregnating cellulose nanofiber (CNF)/multi-walled carbon nanotubes (MWCNTs) aerogel directly into the chitosan solution. The influence of different experimental factors such as the concentration of impregnated chitosan solution, pH value, temperature, and contact time on the CTC adsorption effect was tested. The results showed that the adsorption of CTC reached equilibrium after 2 h. At 25 °C, when the pH value of the solution was four and the concentration of impregnated chitosan was 0.6 wt%, the maximum adsorption capacity was 46.05 mg g⁻¹. CTC was expected to become a new environmentally-friendly adsorbent for copper ion adsorption due to its high adsorption efficiency and use of no toxic substances in the preparation process.