TY - JOUR
T1 - Competition for electrons between reductive dechlorination and denitrification
AU - Cao, Lifeng
AU - Sun, Weihua
AU - Zhang, Yuting
AU - Feng, Shimin
AU - Dong, Jinyun
AU - Zhang, Yongming
AU - Rittmann, Bruce
PY - 2017/12/1
Y1 - 2017/12/1
N2 - It is common that 2,4,6-trichlorophenol (TCP) coexists with nitrate or nitrite in industrial wastewaters. In this work, simultaneous reductive dechlorination of TCP and denitrification of nitrate or nitrite competed for electron donor, which led to their mutual inhibition. All inhibitions could be relieved to a certain degree by augmenting an organic electron donor, but the impact of the added electron donor was strongest for TCP. For simultaneous reduction of TCP together with nitrate, TCP’s removal rate value increased 75% and 150%, respectively, when added glucose was increased from 0.4 mmol∙L–1 to 0.5 mmol∙L–1 and to 0.76 mmol∙L–1. For comparison, the removal rate for nitrate increased by only 25% and 114% for the same added glucose. The relationship between their initial biodegradation rates versus their initial concentrations could be represented well with the Monod model, which quantified their half-maximum-rate concentration (KS value), and KS values for TCP, nitrate, and nitrite were larger with simultaneous reduction than independent reduction. The increases in KS are further evidence that competition for the electron donor led to mutual inhibition. For bioremediation of wastewater containing TCP and oxidized nitrogen, both reduction reactions should proceed more rapidly if the oxidized nitrogen is nitrite instead of nitrate and if readily biodegradable electron acceptor is augmented. [Figure not available: see fulltext.].
AB - It is common that 2,4,6-trichlorophenol (TCP) coexists with nitrate or nitrite in industrial wastewaters. In this work, simultaneous reductive dechlorination of TCP and denitrification of nitrate or nitrite competed for electron donor, which led to their mutual inhibition. All inhibitions could be relieved to a certain degree by augmenting an organic electron donor, but the impact of the added electron donor was strongest for TCP. For simultaneous reduction of TCP together with nitrate, TCP’s removal rate value increased 75% and 150%, respectively, when added glucose was increased from 0.4 mmol∙L–1 to 0.5 mmol∙L–1 and to 0.76 mmol∙L–1. For comparison, the removal rate for nitrate increased by only 25% and 114% for the same added glucose. The relationship between their initial biodegradation rates versus their initial concentrations could be represented well with the Monod model, which quantified their half-maximum-rate concentration (KS value), and KS values for TCP, nitrate, and nitrite were larger with simultaneous reduction than independent reduction. The increases in KS are further evidence that competition for the electron donor led to mutual inhibition. For bioremediation of wastewater containing TCP and oxidized nitrogen, both reduction reactions should proceed more rapidly if the oxidized nitrogen is nitrite instead of nitrate and if readily biodegradable electron acceptor is augmented. [Figure not available: see fulltext.].
KW - 2,4,6-trichlorophenol
KW - Bioremediation
KW - Competition for electrons
KW - Denitrification
KW - Nitrate
KW - Reductive dechlorination
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U2 - 10.1007/s11783-017-0959-x
DO - 10.1007/s11783-017-0959-x
M3 - Article
AN - SCOPUS:85021206029
VL - 11
JO - Frontiers of Environmental Science and Engineering
JF - Frontiers of Environmental Science and Engineering
SN - 2095-2201
IS - 6
M1 - 14
ER -