Abstract
Manganese dioxide nanowhiskers (MDN), prepared by the reduction of potassium permanganate by ethyl alcohol has been investigated as an adsorbent for Hg(II) removal from aqueous medium. Characterization of the as-synthesized material was carried out using transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive analysis of X-rays (EDAX), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD). SEM and TEM data showed that the as-synthesized MDN looks like agglomerated whiskers of 5–10 nm in diameter and 100–300 nm in length. XRD data revealed the formation of birnessite type layered manganese dioxide. Mn(IV) oxidation state of Mn in MDN was confirmed by XPS. Batch experiments were conducted to evaluate the Hg(II) adsorption capacity of MDN. Hg(II) adsorption on MDN is a fast process and the kinetics followed a pseudo-second-order rate equation. The Hg(II) uptake varied with pH and showed optimum performance at pH 6–9. The experimental evidence revealed that physisorption is the dominating mechanism in Hg(II) removal. Considering the practical difficulty in handling nanomaterials, MDN was supported on Al 2O 3 (MDN@Al 2O 3) and the composite was shown to be an efficient adsorbent for Hg(II) from simulated chlor-alkali industrial effluent. The results suggest that this material can be a practical solution for Hg(II) scavenging in several industrial processes.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.