Yenilmez, Aylin EbruErtul, SelinYilmaz, TulayUcar, DenizDi Capua, FrancescoSahinkaya, Erkan2026-02-122026-02-1220232213-29292213-3437https://doi.org/10.1016/j.jece.2023.111325https://hdl.handle.net/20.500.12885/6787P-nitrophenol (PNP) can co-occur with nitrate (NO3-) in industrial and municipal wastewater due to effluent discharges from industry and agricultural activities. In this study, the simultaneous removal of PNP and NO3- was investigated under autotrophic and heterotrophic denitrifying conditions in two bioreactor columns at laboratory scale. Autotrophic denitrification with elemental sulfur showed efficient elimination of both PNP (85 % on average for 5-50 mg/L) and NO3- (99 % on average) even at feed PNP concentration of 50 mg/L. In contrast, the heterotrophic column showed significantly lower PNP removal (53 % on average for 5-50 mg/L) despite denitrification efficiency being >= 95 %. ORP was identified as a possible control parameter to modulate PNP removal efficiency. The autotrophic column showed better resiliency than the heterotrophic one under intermittent feeding of 50 mg/L of PNP. Absorbance spectra and HPLC results revealed no accumulation of PNP by-products, i.e., aminophenol, in the autotrophic column during transient feeding conditions.eninfo:eu-repo/semantics/closedAccessNitrophenolNitrateAutotrophic denitrificationElemental sulfurHeterotrophic denitrificationArticle10.1016/j.jece.2023.111325116WOS:0011012737000012-s2.0-85175170842Q1Q1