23 Sep 2025

Alkaline Hydrolysis for Degrading the Emerging Munitions Contaminant Methylnitroguanidine and Regenerating Graphene Nanoplatelets for Sustainable Adsorption of Munition Compounds

Abstract: Alkaline hydrolysis has proven to be an effective treatment technique for several emerging and legacy munition compounds. This study evaluates its effectiveness in degrading the emerging insensitive MC methylnitroguanidine in comparison to NQ. Additionally, the feasibility of regenerating graphene nanoplatelets following adsorption of MCs, including MeNQ, NQ, NTO, TNT, DNAN, and RDX, is investigated. This study is among the first to successfully evaluate MeNQ treatment and proposes a novel strategy to regenerate GnPs for further environmental remediation. Regeneration performance in high-pH solutions was compared with processes using a 30:70 solution of acetonitrile:water and reagent water alone to further determine pH- and solvent-based interactions. In high-pH solutions, NTO was desorbed via electrostatic repulsion, while the other MCs degraded, generating breakdown products consistent with previous studies and current findings. The aqueous ammonium produced during degradation may have been removed by GnPs. The organic-aqueous blend enhanced MC removal, with recovery largely correlating with aqueous solubility, though π-π interactions may have hindered desorption. Adsorption following desorption with these techniques resulted in higher capacities compared to systems using reagent water alone, where desorption aligned with adsorption isotherms. Overall, this study provides valuable insights into MeNQ treatment and the reuse of GnPs for sustainable water remediation.

31 Mar 2022

Design, Construction, and Testing of the PFAS Effluent Treatment System (PETS), a Mobile Ion Exchange–Based System for the Treatment of Per-, Poly-Fluorinated Alkyl Substances (PFAS) Contaminated Water

Abstract: Poly-,Per-fluorinated alkyl substances (PFAS) are versatile chemicals that were incorporated in a wide range of products. One of their most important use was in aqueous film-forming foams for fighting liquid fuel fires. PFAS compounds have recently been identified as potential environmental contaminants. In the United States there are hundreds of potential military sites with PFAS contamination.The ERDC designed and constructed a mobile treatment system to address small sites (250,000 gallons or less) and as a platform to field test new adsorptive media. The PFAS Effluent Treatment System (PETS) has cartridge filters to remove sediments and a granular activated carbon (GAC) media filter to remove organic compounds that might compete with PFAS in the ion exchange process, although it may also remove PFAS too. The last process is an ion exchange resin specifically designed to remove PFAS to a target level of 70 ng/L or less (equivalent to the US Environmental Protection Agency (EPA) Drinking Water Health Advisory). The system was tested at Hurlburt Field, a US Air Force facility in Florida and at Naval Support Activity (NSA) Mid-South in Millington, TN.

12 May 2021

Application of Incremental Sampling Methodology for Subsurface Sampling

ABSTRACT:  Historically, researchers studying contaminated sites have used grab sampling to collect soil samples. However, this methodology can introduce error in the analysis because it does not account for the wide variations of contaminant concentrations in soil. An alternative method is the Incremental Sampling Methodology (ISM), which previous studies have shown more accurately captures the true concentration of contaminants over an area, even in heterogeneous soils. This report describes the methods and materials used with ISM to collect soil samples, specifically for the purpose of mapping subsurface contamination from site activities. The field data presented indicates that ISM is a promising methodology for collecting subsurface soil samples containing contaminants of concern, including metals and semivolatile organic compounds (SVOCs), for analysis. Ultimately, this study found ISM to be useful for supplying information to assist in the decisions needed for remediation activities.