(Top) Testing degradation of xanthan gum polymer by sodium permanganate. The xanthan gum maintained most of its viscosity through five days, only showing more significant degradation after multiple weeks.
(Bottom) Moderate concentrations of polymer had minimal impact on the oxidation rates of polycyclic aromatic hydrocarbon (PAH) compounds (phenanthrene shown here), which are common contaminants.
Polymer-enhanced in situ chemical oxidation of groundwater contaminants
The objective of this work is to investigate enhanced approaches for oxidizing groundwater contaminants to clean-up contaminated sites, specifically evaluating the use of polymers and surfactants to improve the delivery and effectiveness of injected oxidants. To date, we have completed data sets to (1) allow comparison of oxidant-driven degradation kinetics of six PAH compounds with two polymer concentrations, as well as without polymer; (2) assess the effects of oxidant on the rheological properties of the polymer solutions; (3) determine second-order reaction rate constants for the polymer, allowing direct comparison with rate constants for other contaminant-oxidant combinations; and (4) applying the polymer-enhanced oxidant method to coal tar, a complex mixture of contaminant compounds that is a common source of groundwater contamination. Additional work to investigate alternative polymer-oxidant combinations and the flow of polymers with varying rheological properties in porous media system, which was planned for this year, has been delayed by the COVID-19 shutdown.