pH-Dependent Hydrogenotrophic Denitratation Based on Self-Alkalization

Producing stable nitrite is a necessity for anaerobic ammonium oxidation (anammox) but remains a huge challenge. Here, we describe the design and operation of a hydrogenotrophic denitratation system that stably reduced >90% nitrate to nitrite under self-alkaline conditions of pH up to 10.80. Manually lowering the pH to a range of 9.00–10.00 dramatically decreased the nitrate-to-nitrite transformation ratio to