Co-removal of P-nitrophenol and nitrate in sulfur-based autotrophic and methanol-fed heterotrophic denitrification bioreactors


Yenilmez A. E., Ertul S., Yilmaz T., Ucar D., Di Capua F., Sahinkaya E.

Journal of Environmental Chemical Engineering, vol.11, no.6, 2023 (SCI-Expanded) identifier

  • Publication Type: Article / Article
  • Volume: 11 Issue: 6
  • Publication Date: 2023
  • Doi Number: 10.1016/j.jece.2023.111325
  • Journal Name: Journal of Environmental Chemical Engineering
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, CAB Abstracts, Chemical Abstracts Core, Compendex, INSPEC, Veterinary Science Database
  • Keywords: Autotrophic denitrification, Elemental sulfur, Heterotrophic denitrification, Nitrate, Nitrophenol
  • Istanbul Technical University Affiliated: Yes

Abstract

P-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.