CaCO3-coated PVA/BC-based composite for the simultaneous adsorption of Cu(II), Cd(II), Pb(II) in aqueous solution.

A polymer composite material comprising polyvinyl alcohol/bacterial cellulose/calcium carbonate (PVA/BC/CaCO3) was prepared for enabling the selective adsorption of toxic heavy metal ions, such as Cd(II), Cu(II), and Pb(II) from solution. FT-IR, SEM and XRD analyses confirmed the successful incorporation of CaCO3 into the PVA-based polymer by chemical cross-linking with epichlorohydrin. The optimal pH for adsorption of the metal ions onto PVA/BC/CaCO3 was determined to be 6.0. The pseudo-first-order kinetics model was best-suited for fitting the adsorption kinetics data, and the Langmuir model was best-suited for fitting the thermodynamic adsorption data. The maximum adsorption capacities of PVA/BC/CaCO3 for Cu(II), Pb(II), and Cd(II) were found to be 57.1, 513.6, and 238.6 mg/g, respectively, at 40 °C. In addition, the adsorbent was found to be highly recyclable. Overall, PVA/BC/CaCO3 adsorbent has the applicable potential in the removal of heavy metal ions from contaminated solution.