Grantee Research Project Results

2006 Progress Report: Synthesis and Application of a New Class of Stabilized Nanoscale Iron Particles for Rapid Destruction of Chlorinated Hydrocarbons in Soil and Groundwater

EPA Grant Number: GR832373
Title: Synthesis and Application of a New Class of Stabilized Nanoscale Iron Particles for Rapid Destruction of Chlorinated Hydrocarbons in Soil and Groundwater
Investigators: Zhao, Dongye , Roberts, Christopher B.
Current Investigators: Zhao, Dongye , Roberts, Christopher B. , He, Feng
Institution: Auburn University Main Campus
EPA Project Officer: Hahn, Intaek
Project Period: August 1, 2005 through July 31, 2008 (Extended to July 31, 2009)
Project Period Covered by this Report: August 1, 2005 through July 31, 2006
Project Amount: $280,215
RFA: Greater Research Opportunities: Research in Nanoscale Science Engineering and Technology (2004) RFA Text | Recipients Lists
Research Category: Hazardous Waste/Remediation , Nanotechnology , Safer Chemicals

Objective:

The overall goal of this research is to develop a cost-effective, in-situ remediation technology that employs a new class of dispersed iron-based nanoparticles for rapid destruction of chlorinated hydrocarbons in soil and groundwater. The specific objectives are to: (1) synthesize a new class of stabilized iron-based nanoparticles using low-cost and “green” stabilizers, such as starches and celluloses; (2) test the effectiveness of the stabilized nanoparticles for dechlorination of select contaminants (trichloroethylene [TCE] and polychlorinated biphenyls [PCBs]) in soil and groundwater; and (3) test the feasibility of an in-situ remediation process that is based on the nanoparticles.

Progress Summary:

The major findings are summarized as follows:

We developed a new class of stabilized iron nanoparticles of controlled size and soil mobility by using select water-soluble starch or carboxymethyl cellulose (CMC) as a stabilizer.
We characterized the stabilized nanoparticles with respect to both dechlorination reactivity and soil transportability. Compared to non-stabilized Fe-Pd particles, the stabilized nanoparticles displayed > 37 times greater reactivity for TCE degradation. CMC appears to be a more effective stabilizer than starch. Application of 0.2% (w/w) NaCMC was able to stabilize 0.1 g/L of iron nanoparticles with a mean diameter of 4.3±1.8 nm.
Fourier Transform Infrared Spectroscopy (FTIR) results suggested that CMC molecules were adsorbed to the Fe nanoparticle surface through monodentate complexation and intermolecular hydrogen bonding. The adsorption process results in the encapsulation of the nanoparticles with a thin CMC layer, which prevented the particles from agglomeration.
Column tests showed that the stabilized nanoparticles can be readily transported and distributed in a loamy-sand soil, and then eluted completely with < 3 pore volume of deionized (DI) water, whereas non-stabilized counterparts were completely intercepted by the soil bed.
Factors such as the CMC/Fe²⁺ molar ratio and initial Fe²⁺ concentration; CMC structure, such as molecular weight and degree of substitution; synthesizing temperature; NaBH₄ adding rate and mixing; and synthesizing pH and cations in water significantly affected the stabilization of CMC-stabilized Fe nanoparticles.

Future Activities:

Continue to investigate the reactivity and mobility of the Fe-Pd nanoparticles synthesized under various experimental conditions.
Carry out batch and column degradation experiments in the presence of soils.

Journal Articles on this Report : 1 Displayed | Download in RIS Format

Publications Views
Other project views:	All 35 publications	19 publications in selected types	All 19 journal articles

Publications
Type	Citation	Project	Document Sources
Journal Article	He F, Zhao D, Liu J, Roberts CB. Stabilization of Fe-Pd nanoparticles with sodium carboxymethyl cellulose for enhanced transport and dechlorination of trichloroethylene in soil and groundwater. Industrial & Engineering Chemistry Research 2007;46(1):29-34.	GR832373 (2006) GR832373 (2007) GR832373 (Final)	Abstract: American Chemical Society-Abstract Exit

Supplemental Keywords:

carcinogen, chemicals, clean technologies, cleanup, DNAPL, drinking water, groundwater, innovative technology, nanotechnology, NAPL, organics, PCBs, reduction, remediation, TCE, toxics, water,, Sustainable Industry/Business, RFA, Scientific Discipline, TREATMENT/CONTROL, Waste, Water, Technology for Sustainable Environment, Sustainable Environment, Environmental Chemistry, Contaminated Sediments, Treatment Technologies, Environmental Engineering, chlorinated aromatic hydrocarbons (CAHs), chlorinated hydrocarbons (CHCs), nanomaterials, nanoparticle remediation, contaminated sediment, dechlorination, contaminated groundwater, decontamination, nanotechnology, groundwater rememdiation

Progress and Final Reports:

Original Abstract

The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.