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Adsorption is a preferred decontamination process for the treatment of industrial effluents, and various materials have been developed for this purpose. In the present work, esters based on sulfonated poly(ether ketone)/ionic liquids were prepared and their structures were evaluated by Fourier transform Infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopies. Batch adsorption experiments were carried out on a mixed solution comprising Pb2+, Cu2+, Cd2+ and Zn2+ ions with concentration ranging from 4 to 10 μg L-1. The adsorption affinity of the esters expressed as the equilibrium metal ions uptake capacity, qe (mg g-1) was in the order: Pb2+ (6.2), Cd2+ (5.1), Cu2+ (2.8) and Zn2+ (0.8). It was interesting to observe the low values of qe of all adsorbents for Zn2+, which is advantageous in the treatments of wastewater as Zn2+ present in high concentration and could reduce the ion exchange capacity of the adsorbent largely toward other metal ions pollutant. Esterification with ionic liquids open the opportunity to upcycle polymer wastes that can be sulfonated, such as polystyrene, PEEK and its cross-linked form.

Discharge of untreated industrial wastewater containing heavy metals such as Pb2+ is hazardous to the environment due to their high toxicity. This study reports on the adsorption, desorption, and kinetic study on Pb2+ removal from aqueous solutions using wood/Nano-manganese oxide composite (WB-NMO). The optimum pH, contact time and temperature for adsorption were found to be 5.0, 4 h and 333 K, respectively. Pseudo-second-order kinetics best described the adsorption process with an initial sorption rate of 4.0 mg g min-1, and a half-adsorption time t1/2 of 31.6 min. Best fit for adsorption isotherm was obtained with the Brunauer-Emmett-Teller (BET) model with a maximum adsorption capacity of 213 mg/g for an initial metal concentration of 60 mg/L. Both intra-particle diffusion and film diffusion contribute to the rate-determining step. Desorption experiments with 0.5 mol/L HCl, inferred the reusability of the composite. Adsorption experiment of Pb2+ from industrial wastewater confirmed that the prepared WB-NMO is a promising candidate for wastewater treatment. The WB-NMO demonstrated high Pb2+ removal efficiency and is considered as a promising alternative and reusable composite for lead removal from contaminated effluents.