Performance of membrane photocatalytic reactor incorporated with ZnO-Cymbopogon citratus in treating palm oil mill secondary effluent

• Published in: Process safety and environmental protection Vol. 143; pp. 273 - 284
• Main Authors: Sidik, Dilaeleyana Abu Bakar, Hairom, Nur Hanis Hayati, Ahmad, Mohd Khairul, Madon, Rais Hanizam, Mohammad, Abdul Wahab
• Format: Journal Article
• Language: English
• Published: Rugby Elsevier B.V 01.11.2020; Elsevier Science Ltd
• Subjects: Chemical precipitation; Color; Cymbopogon citratus; Effluent treatment; Effluents; Fourier transforms; Infrared spectroscopy; Membrane photocatalytic reactor; Membrane processes; Membranes; Nanoparticles; Palm oil; Palm oil mill secondary effluent; Photocatalysis; Plant extracts; Precipitation; Reactors; Synthesis; Transmission electron microscopy; Turbidity; Vegetable oils; Wastewater treatment; X-ray diffraction; Zinc oxide; Membrane photocatalytic reactor; Zinc oxide; Precipitation; Cymbopogon citratus; Palm oil mill secondary effluent
• ISSN: 0957-5820; 1744-3598
• DOI: 10.1016/j.psep.2020.06.038

•Green synthesize of ZnO nanoparticle using different concentration of ZnO solution.•The ZnO-CC 3:1 indicated smaller size (6.6–42.9 nm) of nanoparticles.•Photocatalytic process with ZnO-CC resulting higher colour degradation of POMSE and minimize membrane fouling in membrane photocatalytic reactor (MPR). Green synthesis provides new avenues of nanoparticle synthesis using plants. In the present study, we attempted to synthesise ZnO nanoparticles via precipitation using different ratios of ZnO solution to leaf extract of Cymbopogon citratus (3:1, 5:1, and 9:1). The modified ZnO was characterised using Fourier transform infrared spectroscopy, transmission electron microscopy, and X-ray diffraction. The influences of the modified ZnO-C. citratus (ZnO-CC) nanoparticles on the removal of colour from and decline in the flux of palm oil mill secondary effluent (POMSE) in a membrane photocatalytic reactor (MPR) were studied. The performance of ZnO-CC 3:1 in terms of colour (99.84 %), COD (98.97 %), BOD (96.24 %) and turbidity removal (99.89 %) of the treated POMSE was significant. The improvement of the performance efficiency for POMSE treatment using MPR correlate with the reduction in the size of ZnO-CC 3:1 (6.6–42.9 nm) which promote higher degradation activity and minimize membrane flux decline during the process. Thus, it can be deduced that the coupled MPR system has significant potential for application in the palm oil mill effluent treatment industry as it mitigates membrane fouling and yields treated effluent of good quality.