Synthesis of aminated cellulose and its adsorption properties for heavy metals from aqueous solution

Cotton contains a large amount of cellulose polymer, which has good application potential for removing pollutants from wastewater due to its broad availability, low-cost, and rich functional groups. In this work, absorbent cotton was grafted with polyethylene polyamine chains on the surfaces of the cotton fibers to obtain the modified cotton adsorbent triethylenetetramine carboxymethyl cellulose amide. The surface morphology and chemical structure of this adsorbent were characterized via FTIR, 13 C NMR spectroscopy, and SEM/EDS. In addition, the adsorption performances of this adsorbent for Cu 2+ , Pb 2+ , and Cd 2+ ions were evaluated via ICP spectroscopy. The results of the adsorption experiment indicate that the modified cotton adsorbent exhibited coordination properties and affinity for multiple metal ions. The fitting results of kinetic models showed that the adsorption was dominated by chemisorption, and the adsorption process involved both monolayer and multilayer adsorption. The maximum adsorption capacities for Cu 2+ , Pb 2+ , and Cd 2+ were estimated to be 38.07, 94.27, and 195.39 mg/g, respectively. Therefore, this adsorbent derived from the abundant natural material cotton has great potential for treating wastewater polluted with heavy metals.