Immobilization of mercury by pyrite (FeS2).
Elemental mercury (Hg(0)) is a metal with a number of atypical properties, which has resulted in its use in myriad anthropogenic processes. However, these same properties have also led to severe local subsurface contamination at many places where it has been used. As such, we studied the influence of various parameters on Hg(II) sorption onto pyrite (pH, time, Hg(II) concentration), a potential subsurface reactive barrier. Batch sorption studies revealed that total Hg(II) removal increases with both pH and time. X-ray absorption spectroscopy analysis showed that a transformation in the coordination environment at low pH occurred during aging over 2 weeks, to form an ordered monolayer of monodentate Hg-Cl complexes on pyrite. In column studies packed with pure quartz sand, the transport of Hg(II) was significantly retarded by the presence of a thin pyrite-sand reactive barrier, although dissolved oxygen inhibited Hg(II) sorption onto pyrite in the column.
Bower
Julia
J
Department of Civil Engineering, Auburn University, 238 Harbert Engineering Center, Auburn, AL 36849, USA.
Savage
Kaye S
KS
Weinman
Beth
B
Barnett
Mark O
MO
Hamilton
William P
WP
Harper
Willie F
WF
D015502:Absorptiometry, Photon; D000327:Adsorption; D004784:Environmental Monitoring / Q000379:methods; D004785:Environmental Pollutants / Q000032:analysis / Q000737:chemistry*; D052918:Environmental Restoration and Remediation / Q000379:methods*; D006863:Hydrogen-Ion Concentration; D007501:Iron / Q000032:analysis / Q000737:chemistry*; D008628:Mercury / Q000032:analysis / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D011791:Quartz; D013440:Sulfides / Q000032:analysis / Q000737:chemistry*; D013995:Time
D004785:Environmental Pollutants; D013440:Sulfides; C011342:pyrite; D011791:Quartz; D007501:Iron; D008628:Mercury