Adsorption of Mn (II) ion on polyvinyl alcohol/chitosan dry blending from aqueous solution

• The preparing of PVA/CS hydrogel.
• Applied PVA/CS nanoparticles as a Mn (II) ion adsorbent.
• Using ball milling as blending method.
• Ball milling is considered as friendly environmental method.

The present study explored the ability of polyvinyl alcohol/chitosan (PVA/CS) binary dry blend as an adsorbent for removal of Mn (II) ion from aqueous solution. We will study how the solid-state shear ball milling is employed to prepare the polyvinyl alcohol/chitosan hydrogel crosslinked without using the crosslinking agent. The PVA/CS was characterized by LDS, X-ray diffraction, FTIR and SEM. The results revealed that during the process of ball milling at ambient temperature, a PVA/CS blending can be effectively pulverized resulting in crosslinking of PVA/CS hydrogel having nanosized particles. Also, the removal of Mn (II) ion has been found to be pH, adsorbent dosage and contact time dependent and the optimum pH was 6.0. From the testing of equilibrium data by Langmuir and Freundlich isotherm models, it was found that the adsorption equilibrium was fitted well by Freundlich isotherm model. In addition, the kinetic adsorption was fitted well by the pseudo-second-order kinetic model. The thermodynamic study indicated that the adsorption of Mn (II) ion onto PVA/CS was spontaneous and endothermic in nature. Also, it showed that the PVA/CS binary blend was a good adsorbent for the removal of Mn (II) ion from aqueous solution.

The SEM images indicate that the surface was quite rough and dense in nature and thus provide maximum surface area for the adsorption of Mn (II) ion.Figure optionsDownload as PowerPoint slide