Acetonitrile wastewater treatment enhanced by a hybrid membrane-aerated bioreactor containing aerated and non-aerated zones.

•A membrane-aerated bioreactor (MAB) with aerated and non-aerated zones was constructed.•HF-MAB and SR-MAB were used to enhance acetonitrile (ACN) wastewater treatment.•Two zones synergistically promoted ACN degradation, nitrification and denitrification.•HF-MAB achieved an ACN removal loading of 1.116 kg/m3·d without secondary pollution.•The performances of the HF-MAB were slightly better than those of the SR-MAB.