Optimization of magnetic powdered activated carbon for aqueous Hg(II) removal and magnetic recovery

Emily K. Faulconer, Natalia V.Hoogesteijn von Reitzenstein, David W. Mazyck

Research output: Contribution to journalArticlepeer-review

104 Scopus citations

Abstract

Activated carbon is known to adsorb aqueous Hg(II). MPAC (magnetic powdered activated carbon) has the potential to remove aqueous Hg to less than 0.2μg/L while being magnetically recoverable. Magnetic recapture allows simple sorbent separation from the waste stream while an isolated waste potentially allows for mercury recycling. MPAC Hg-removal performance is verified by mercury mass balance, calculated by quantifying adsorbed, volatilized, and residual aqueous mercury. The batch reactor contained a sealed mercury-carbon contact chamber with mixing and constant N 2 (g) headspace flow to an oxidizing trap. Mercury adsorption was performed using spiked ultrapure water (100μg/L Hg). Mercury concentrations were obtained using EPA method 245.1 and cold vapor atomic absorption spectroscopy. MPAC synthesis was optimized for Hg removal and sorbent recovery according to the variables: C:Fe, thermal oxidation temperature and time. The 3:1 C:Fe preserved most of the original sorbent surface area. As indicated by XRD patterns, thermal oxidation reduced the amorphous characteristic of the iron oxides but did not improve sorbent recovery and damaged porosity at higher oxidation temperatures. Therefore, the optimal synthesis variables, 3:1 C:Fe mass ratio without thermal oxidation, which can achieve 92.5% (±8.3%) sorbent recovery and 96.3% (±9%) Hg removal. The mass balance has been closed to within approximately ±15%.

Original languageEnglish (US)
Pages (from-to)9-14
Number of pages6
JournalJournal of Hazardous Materials
Volume199-200
DOIs
StatePublished - Jan 15 2012

All Science Journal Classification (ASJC) codes

  • Environmental Engineering
  • Environmental Chemistry
  • Waste Management and Disposal
  • Pollution
  • Health, Toxicology and Mutagenesis

Fingerprint

Dive into the research topics of 'Optimization of magnetic powdered activated carbon for aqueous Hg(II) removal and magnetic recovery'. Together they form a unique fingerprint.

Cite this