SYNTHESIS OF MAGNETITE-DERIVED ZERO VALENT NANOIRON AND
TARGETING OF ZERO VALENT IRON FOR APPLICATION IN
ENVIRONMENTAL REMEDIATION
Open Access
Author:
Fowler, Daniel
Area of Honors:
Chemistry
Degree:
Bachelor of Science
Document Type:
Thesis
Thesis Supervisors:
Dr. Tom Mallouk, Thesis Supervisor Thomas E Mallouk, Thesis Supervisor Przemyslaw Maslak, Thesis Honors Advisor Raymond Edward Schaak, Faculty Reader
Keywords:
environmental remediation nanoiron iron targeting
Abstract:
Dense non-aqueous phase liquids (DNAPLs) form underground contamination zones that are vast and heterogeneous in their spatial distribution, making them both difficult and costly to remediate. The use of nanoscale zero valent iron (NZVI) as an in-situ agent is a good method for reducing contaminants to less toxic forms, but it is limited by cost, scalability, and hazardous synthetic routes. A new inexpensive and environmentally benign synthetic technique of making carbon-adsorbed NZVI from the reduction of iron oxide (magnetite) with carbon black was developed. Powder X-ray diffraction and scanning electron microscopy confirmed that charged polyelectrolytes were necessary to promote sufficiently intimate mixing of the reactants for production of NZVI. Transmission electron microscopy revealed iron particles on the order of 50 to 150 nm diameter. Delivery of nanoparticles to subterranean contamination zones was modeled by the transport of carbonyl iron powder suspended in anionic polymer solutions through sand columns. Iron particles modified with different anionic polymers were found to target dichlorobenzene-coated sand grains with different degrees of effectiveness. Trends in targeting correlated well with the surface energies of the polymer-modified iron surfaces, which were measured by the contact angle method. The experimental results indicate that NZVI can be produced in a new inexpensive, green manner and that the contaminant targeting properties of micron-sized iron particles can be effectively tailored using simple polymeric adsorbents.
