(332f) Adsorption on NDMA on Biomass-Derived Activated Carbons in Lab-Scale Columns

The purpose of this research is to test the ability of biochars made from local agroforestry and forestry wastes, to adsorb N-nitrosodimethylamine (NDMA) at very low concentrations out of water. According to the EPA, NDMA is a probable human carcinogen found in ground and drinking water, especially in ground water near rocket testing sites that used unsymmetrical dimethylhydrazine fuel. The treatment standards for NDMA typically range from 1 to a few ng/L (parts per trillion), which creates analytical challenges for monitoring and development of remediation methods.

In this study, biochars produced from pecan shells and local forestry waste were tested in a lab-scale column for adsorption of NDMA. Concentrations of carbon-14-labeled NDMA in well water obtained near a NASA rocket-test site were measured at regular time intervals over the course of the flow through the biochar-filled column for several adsorbents. Liquid scintillation counting was used for quantification to enable faster and most consistent results with smaller sample sizes. Data from the breakthrough curves was used to calculate column design parameters to estimate the cost of adsorption treatment.