Effect of free nitrous acid on nitritation process: Microbial community, inhibitory kinetics, and functional
Yucan Liu1, Yuliang Zhu1, Daishun Wu2
1School of Environmental and Material Engineering, Yantai University, Yantai 264005, China; School of Civil Engineering, Yantai University, Yantai 264005, China.
Abstract:
This work comprehensively deciphered the effect of free nitrous acid (FNA) on the microbial community, inhibitory kinetics, and nitrifiers in nitritation process. Nitritation was first successfully achieved through selective inhibition of free ammonia (FA) on nitrite oxidizers (NOB). Then, batch tests clearly showed that FNA significantly inhibits the ammonia oxidation rate (rsu) and the growth rate (μ) of ammonia oxidizers (AOB), which was well described by the Hellinga model (KI = 0.222 mg·L-1). The structural equation model indicated that FNA was significantly and negatively associated with rsu, μ, Nitrosomonas, Commamons, Nitrospira, and Nitrotoga and positively correlated with Paracoccus. Furthermore, Nitrosomonas significantly drove the ammonia utilization and growth of AOB and was identified as the most important functional biomarker indicating the nitritation in response to FNA levels using random forest model. This study provides helpful information on the kinetics of the mechanism underlying the FNA inhibition on nitrification.
Related Concept Videos
2° Amines to N-Nitrosamines: Reaction with NaNO2
Inorganic Nitrogen Assimilation
1° Amines to Diazonium or Aryldiazonium Salts: Diazotization with NaNO2 Overview
The nitrous acid is unstable. Hence, it is formed in situ from a solution of sodium nitrite and cold aqueous acids such as hydrochloric or sulfuric acid. In an acidic solution, the –OH group of nitrous acid undergoes protonation to give oxonium ion, followed by...
Metabolism of Chemolithotrophs
1° Amines to Diazonium or Aryldiazonium Salts: Diazotization with NaNO2 Mechanism
Overview of Nitrogen Metabolism
The largest pool of nitrogen available in the terrestrial ecosystem is gaseous nitrogen (N2) from the air, but this...


