Adsorption equilibrium and kinetic studies on effective removal of heavy metals onto modified cellulose bearing Schiff base with pyridine chelating groups from aqueous solution

A novel chemically modified cellulose (Cell-Py) adsorbent bearing chelating groups such as pendent Schiff base with pyridine chelating groups was synthesised. The new modified cellulose was examined for the removal of heavy metal ions (Cu(II) and Pb(II)) from aqueous solution. The experimental conditions and adsorption parameters, such as pH, contact time, adsorbent dose, temperature and initial metal ion concentration were optimised. The structural characteristics of the adsorbent were determined using FT-IR, solid state 13C-NMR, SEM, EDX and TGA analysis. Adsorption kinetic parameters of pseudo-first-order, pseudo-second-order and intraparticle diffusion models were used to fit the experimental data. Adsorption isotherms such as Langmuir and Freundlich have been investigated. Also, the thermodynamic parameters ΔG°, ΔH° and ΔS° have been evaluated. The Cell-Py adsorbent can be effectively regenerated with significant level of adsorption after several uses. The biocidal results of Cell-Py showed that toxic effect to the selective bacterial species.