Water Sanitization by the Elimination of Cd2+ Using Recycled PET/MWNT/LDH Composite: Morphology, Thermal, Kinetic and Isotherm Studies
The fabrication and characterization of recycled polyethylene terephthalate nanocomposites (R-PET NCs) reinforced with multiwalled carbon nanotubes/Mg–Al mixed metal oxides (MWNT/LDH) is reported in this study. The morphology images and X-ray diffraction indicated that the MWNT/LDH hybrids were mostly exfoliated in the R-PET matrix. The good dispersion of filler in the R-PET caused MWNT/LDH to operate as a gas barrier and slowed down the thermal degradation of the R-PET matrix. The prepared composite was further employed to eliminate Cd2+from aqueous media. The influence of pH, contact time, coexist ions, temperature, and initial pollutant concentration on the sorption procedure was examined. The high removal efficiency was gained for the Cd2+ sorption by R-PET/MWNT/LDH NC 4 wt %. The sorption equilibria were well explained by both the Freundlich and Langmuir models. The adsorption kinetics of Cd2+ onto R-PET/MWNT/LDH NC 4 wt % could be well described by the pseudo-second-order model. The extracted E value from the Dubinin–Radushkevich equation and thermodynamic data proposed that the sorption was mainly physical. In addition, without the use of magnetic separation, prepared sorbent could be simply collected and reused.