Characterization and Performance Evaluation of Cellulose Acetate-Polyurethane Film for Lead II Ion Removal

Global pollution from toxic metal waste has resulted in increased research on toxic metal adsorption. A cellulose acetate-polyurethane (CA-PU) film adsorbent was successfully prepared in this research. The cellulose acetate-polyurethane film adsorbent was prepared with a polycondensation reaction between cellulose acetate and methylene diphenyl diisocyanate. The CA-PU bond formation was confirmed by functional group analysis obtained from Fourier transform infrared (FTIR) spectroscopy. The obtained film was characterized for improved tensile and thermal properties with the addition of methylene diphenyl diisocyanate (MDI). The adsorption ability of the obtained film was evaluated with laser-induced breakdown spectroscopy (LIBS). The best film adsorbent from the LIBS was selected and studied for adsorption isotherm. The FTIR analysis confirmed the formation of the CA-PU bond from the polycondensation between cellulose acetate and the methylene diphenyl diisocyanate. The result showed that the addition of methylene diphenyl diisocyanate (MDI) resulted in the urethane network's growth. The characterization result showed an improvement in the morphology, thermal stability, and tensile strength of the film. The LIBS studies showed improvement in the adsorption of Pb²⁺ with CA-PU compared with the neat CA. The isotherm studies revealed that Pb²⁺ adsorption by cellulose acetate-polyurethane film adsorbent was heterogeneously dependent on the Freundlich isotherm model (R² = 0.97044). Overall, the polycondensation method proposed by this study enhanced the Pb²⁺ removal, and was comparable to those reported in previous studies.