Synthesis and characterization of mackinawite nanocrystals (FeSm) and their application in recovery of aqueous Hg(II) solution

摘要

Stabilized FeSm (Mackinawite) nanocrystals have been synthesized by hydrothermal treatment of single precursor polymer metal complex. The polymer metal complex was prepared by the reaction of thiourea-formaldehyde resin with metal Fe(II) ion. The synthesized FeSm nanocrystals were characterized by X-ray spectrometry and electronic microscopy. The transmission electron microscopy micrographs showed needle shaped nanocrystals and the thickness and length of these nanocrystals were found to be 12 +/- 3 and 120 +/- 5nm, respectively. The lattice fringes in the HRTEM images, with d-spacing 0.521 +/- 0.005nm very close to (001) plane of mackinawite nature. The interaction between aqueous Hg(II) and synthetic FeSm was studied via batch sorption experiments. The maximum absorption capacity of FeSm has been found with 0.001:0.08M ratio of Hg(II) and FeSm, while the minimum absorption capacity was found with 0.001:0.005M ratio of Hg(II) and FeSm and removed only 60% of Hg(II) from aqueous solution. Batch studies revealed that FeSm nanocrystals were effectively remove Hg(II) from aqueous solution along a broad pH range.