Octahedral Molecular Sieve Manganese Oxide: Feasible Material for Hg(II) Remediation

Abstract

Manganese-oxide material prepared by simple sol-gel method was used as an adsorbent of Hg(II) in aqueous solution. X-ray diffraction pattern and Raman spectroscopy were conducted to prove the cryptomelane crystal. The Hg(II) adsorption behavior of the synthesized material well obeyed kinetic models of pseudo-second-order and Elovich equations indicating a chemisorption from the collected kinetic parameters. 500 mgHg2+/gcryptomelane of equilibrium uptake capacity from pseudo-second-order and 7.87x103 mgHg2+/gcryptomelane/day of initial adsorption rate from the Elovich model were obtained for adsorption of Hg2+ cation over cryptomelane adsorbent. Desorption constant of 0.018 gcryptomelane/mgHg is a significant small value, in comparison to initial adsorption rate, proposing a possible chemisorption for remediation of Hg(II) on cryptomelane structure.