Grantee Research Project Results

Predictive Transport Model of Natural Colloids and Engineered Nanomaterials in Porous Media

EPA Grant Number: FP917805
Title: Predictive Transport Model of Natural Colloids and Engineered Nanomaterials in Porous Media
Investigators: Rasmuson, Jacqueline Anna
Institution: University of Utah
EPA Project Officer: Lee, Sonja
Project Period: September 1, 2015 through August 31, 2018
Project Amount: $132,000
RFA: STAR Graduate Fellowships (2015) RFA Text | Recipients Lists
Research Category: Academic Fellowships

Objective:

Engineered nanomaterials present novel environmental solutions and problems. Due to their high reactivity and surface-area-to-volume ratio, ENMs may travel further distances in the environment than their macroscopic counterparts, and may pose unique health risks that have not yet been addressed. My research will focus on the effects of surface roughness, aggregation, charge heterogeneity, and density on ENM attachment and detachment in the environment.

Approach:

I will concentrate on providing a model that predicts ENM transport in the environment. The model will incorporate hydrodynamic as well as colloidal (i.e. van der Waals, electric double layer, steric, and Born) forces that act on nanoparticles. I will incorporate surface roughness by conducting atomic force microscopy (AFM) experiments, which will be used to calibrate ENM and collector (i.e. sand) surfaces. In conjunction with this work, I will conduct impinging jet and column experiments for a variety of ENMs in order to elucidate attachment at the pore-scale, and to validate the applicability of the model at the continuum-scale. Due to the computationally intensive nature of my research, I will provide correlation equations in order to make my findings accessible to others.

Expected Results:

Due to the various unique properties of ENMs, including high surface to volume ratios and diffusivity, I expect ENM transport to differ from their macro-counterparts. I expect ENMs with a high density and a tendency to aggregate will show more retention in column and jet experiments than ENMs with a low density and/or aggregation tendency. I expect my model to predict well the field-scale tranport of ENMs because my model will incorporate the nano-scale interactions that dictate continuum-scale behavior.

Supplemental Keywords:

Engineered Nanomaterials, Colloid Transport, Water Quality

Progress and Final Reports:

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.