Effect of chemical modification of cotton cellulose by anthranilic acid on the sorption of Cu(II) and Fe(II) ions

Abstract

The authors modified cotton cellulose with anthranilic acid to obtain a new sorbent capable of efficient extraction of heavy metal ions from aqueous solutions. We conducted the modification in two stages: at the first stage, we obtained dialdehyde cellulose by oxidation of cellulose with sodium metaperiodate; at the second stage, we treated dialdehyde cellulose with anthranilic acid to obtain a ready-made sorbent. The authors determined the optimum conditions for modifying cotton cellulose to achieve maximum sorption of iron(II) and copper(II) ions. We studied the equilibrium-kinetic characteristics of the original and modified cotton cellulose. Also, we have processed the results of the kinetic experiment within the framework of pseudo-first- and pseudo-second-order kinetics models. We selected sorption isotherms, processed them within the framework of the Langmuir model, and determined the values of the ultimate sorption capacity (A∞). The modification of cotton cellulose enables to increase its sorption capacity significantly. According to the results, the A∞ of the modified sorbent is about 4-5 times higher than the ultimate sorption capacity of native cotton cellulose to Cu(II) and Fe(II) ions. In contrast, we obtained and compared the IR spectra of anthranilic acid-modified cellulose and native cellulose. Additionally, we obtained SEM images of the modified sorbent and the native cotton cellulose surface structure.