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[Display omitted] • Pseudomonas sp. G16 was isolated with nitrification-denitrification ability. • Efficient removal of inorganic nitrogen at 15℃-30℃ under aerobic conditions. • No accumulation of NO 2 –-N was detected during nitrogen removal. • The nitrogen removal rate of immobilized pellets was increased by about 20%. From the aerobic pond of the farm, the Pseudomonas sp. G16 was screened and isolated, which was confirmed to exhibit heterotrophic nitrification and aerobic denitrification. The removal rates of Ammonia (100 mg/L), nitrate (120 mg/L), and nitrite (100 mg/L) by the strain were 94.13%, 92.62%, and 85.67%, and the nitrogen metabolism pathway of strain G16 was analyzed by whole genome sequencing combined with its nitrification-denitrification intermediate products, it was found that the strain had independent nitrification-denitrification ability and no nitrite accumulation. Under the conditions of carbon source of sodium succinate hexahydrate, C/N ratio of 15, pH of 7.5, temperature of 15 °C, and DO of 210 rpm, strain G16 showed excellent denitrification performance. Strain G16 was prepared into biochar-based immobilized bacterial particles, which successfully improved its nitrogen removal efficiency and stability. Therefore, the application of strain G16 in the field of real wastewater treatment has very necessary research value. [ABSTRACT FROM AUTHOR]

Designing a highly-active electro-Fenton (EF) catalytic membrane without the additional chemicals and iron sludge formation was a challenge for antibiotics treatment. In this study, we constructed Fe/N co-doping biochar (Fe-g-C 3 N 4 /biochar) based ultrafiltration membranes for degradation of tetracycline (a common antibiotic) and membrane fouling control under electro-assistance. The results showed that membranes presented high electro-Fenton catalytic activity because the presence of rich oxygen functional groups (high C–O/C O ratio) and nitrogen species (pyridinic N and pyrrolic N) promoted H 2 O 2 generation and accelerated Fe(III)/Fe(II) cycle. Moreover, H 3 PO 4 activation of biochar endowed the EF catalytic membrane with higher electrocatalytic activity, while it was opposite using biochar with higher pyrolysis temperature (600–700 °C). In particular, owing to the oxidative degradation by electro-generated •OH and •O 2 −, Fe-g-C 3 N 4 /ABC-600/Graphite/PVDF (600 represented the pyrolysis temperature) membrane presented 100% tetracycline removal within 0.749 min of residence time, excellent self-cleaning performance (flux recovery = 100%) at neutral pH and low energy consumption (0.199 W h/L) for the reclamation of synthetic municipal wastewater effluent. In addition, membrane self-cleaning mechanism was closely related to the synergy between partial mineralization and reduced fouling potential of foulants. Besides, the EF membrane also exhibited good reusability and stability, which was promising to apply in antibiotics removal. [Display omitted] • High-active electro-Fenton membrane was prepared with Fe/N co-doping biochar. • The electro-Fenton membrane can quickly remove antibiotics in water at neutral pH. • Membrane performance can be easily modulated by controlling the biochar structure. • The electro-Fenton membrane enabled excellent self-cleaning ability and stability. [ABSTRACT FROM AUTHOR]