| Autor: |
Marcet, Tyler F., Ca´piro, Natalie L., Morris, Lawrence A., Hassan, Sayed M., Yang, Yi, Lo¨ffler, Frank E., Pennell, Kurt D. |
| Zdroj: |
Environmental Science & Technology; 20240101, Issue: Preprints |
| Abstrakt: |
Thermal treatment of soil and groundwater may provide an in situsource of soluble organic compounds and hydrogen (H2) that could stimulate microbial reductive dechlorination (MRD) at sites impacted by chlorinated solvents. The objectives of this study were to identify and quantify the release of electron donors and fermentable precursors during soil heating and to estimate availability of these compounds following thermal treatment. Fourteen solid materials containing <0.01 to 63.81 wt % organic carbon (OC) were incubated at 30, 60, or 90 °C for up to 180 d, leading to the release of direct electron donors (i.e., H2and acetate) and fermentable volatile fatty acids (VFAs). Total VFA release ranged from 5 ± 0 × 10–9carbon per gram solid (mol C/gs) during 30 °C incubation of quartz sand to 820 ± 50 × 10–6mol C/gsduring 90 °C incubation of humic acid, and was positively impacted by incubation time, temperature, and solid-phase OC content. H2gas was detected at a maximum of 180 ± 50 × 10–9mol H2/gs, accounting for less than 0.3% of reducing equivalents associated with VFAs released under the same conditions. These findings will allow for more reliable prediction of substrate release during thermal treatment, supporting the implementation of coupled thermal and biological remediation strategies. |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
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