(562ac) Magnetically Recoverable Carbon-Coated Iron Carbide for Organic and Arsenic Adsorptive Removal

Authors: 
Powell, C., Rice University
Guo, S., Rice University
Wong, M. S., Rice University
Atkinson, A. J., Arizona State University
Godret-Miertschin, L. M., Rice University, Abercrombie C140
Ventura, K., University of Texas at El Paso
Lounsbury, A. W., Yale University
Villagran, D., University of Texas at El Paso
Zimmerman, J. B., Yale University
Westerhoff, P., Arizona State University
Magnetic particles, generally nanostructured and magnetite-based, have been used extensively to remove drinking water contaminants. Compositions alternative to Fe3O4 could address long-standing issues of magnetic recoverability and materials integrity in real waters. The stability, magnetic separability, and adsorptive properties of nanostructured carbon-coated iron carbide (Fe3C@C) were compared to those of Fe3O4 and other common iron oxide-based nanomaterials. Experimental results show that (i) Fe3C@C is chemically stable in simulated drinking water, (ii) can be separated from water magnetically under flow with greater than 99% recovery, and (iii) has a 100´ higher adsorption capacity for methylene blue (39.8 mg/g) than Fe3O4 and a comparable adsorption capacity for arsenic (168 µg/g). These properties suggest Fe3C@C as a viable magnetic engineered nanomaterial (ENM) for the removal of organics and oxo-anions with further development.