The role of Water Chemistry and Natural Organic Matter on the Treatment of Emerging Contaminants of concern
Citation:
Tegenaw, A., E. Sahle-Demessie, Ben Mezgebe, AND M. Nadagouda. The role of Water Chemistry and Natural Organic Matter on the Treatment of Emerging Contaminants of concern. American Chemical Society Annual Spring Meeting 2024, New Orleans, LA, March 17 - 21, 2024.
Impact/Purpose:
This work deals on the effect of organic matter and water chemistry on the treatment of micropollutants. An example is the the use of polymeric adsorbents that are easily regenerated (soft washing) and their surface could be modified (polar/non-polar) to remove specific contaminants. Furthermore, polymeric adsorbents have lower costs than activated carbon, while recycled plastic can be converted to the adsorbents.
Description:
Emerging contaminants of concern (ECCs), such as flame retardants and per- and poly-fluoroalkyl substances (PFAS), are frequently detected in various environmental compartments and biological matrices/species due to widespread use and release through different exposure pathways. The persistence, mobility, bioconcentration, bioaccumulation, and biomagnification of such anthropogenic compounds in the environment have posed immense ecological and human health concerns. Treatment options that are commonly considered for ECCs from drinking water include adsorption using conventional adsorbents. Granular activated carbon and ion exchange resins are widely used sorbents for PFAS treatment. However, both have critical limitations towards short-chain PFAS and interference with dissolved ions and natural organic matter (NOM). Polymeric adsorbents, such as polyamides, are gaining attention due to convenience, cost-effectiveness, higher efficiency, versatility, all-inclusiveness, and regeneration capacity. The performance of such adsorbents depends on particle size, pore size, specific surface area, and solution chemistry (pH, co-existing ions, and NOM). The adsorption of short- and long-chain PFAS that include hydroxylic and sulfonic groups and GenX is tested in synthetic and real waters using batch equilibrium studies. The effectiveness of such adsorbents is investigated as a function of solution pH, competing ions, and NOM at different concentrations/scales. The findings of this work provide insight into the potential application and performance efficiency of polyamide polymers in the treatment of emerging contaminants of high concern as a function of solution chemistry and NOM.