No abstract

Performance and reusability of different zinc oxide nanoparticles (ZnO-PVP and ZnO-PEG) for photocatalytic degradation of palm-mill oil effluent (POME) has been studied. The nanoparticles properties were characterised with fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and transmission electron microscopy (TEM). The TEM results show that ZnO-PEG nanoparticles exhibit the smaller size than ZnO-PVP with less agglomeration. It was found that ZnO-PEG shows better effectiveness than ZnO-PVP in reducing turbidity, colour and increasing the dissolved oxygen (DO). By using two types of reusability methods: (a) oven drying (b) hot water rinsing, the oven drying method portrayed the most efficient route for POME treatment. This research would be a solution to the palm oil industry for photocatalyst recovering as well as reduction of the chemical usage in order to meet the development of advanced and greener technologies.

Due to the lack of studies regarding the potential of polyvinylpyrrolidone (PVP) as capping agent in precipitation of zinc oxide (ZnO) nanoparticles, this research focused on the performance of ZnO nanoparticles with presence of PVP loading on photocatalytic degradation treatment for industrial dye wastewater. Three different samples of ZnO-PVP were successfully synthesized via precipitation method. The degradation rate of dye approached 90.61% under pH7 in the presence of ZnO-PVP (0.025g/L of PVP). The chemical bonds in ZnO-PVP was analysed using Fourier Transform Infrared Spectroscopy (FTIR).

Industrial textile wastewater can be considered as main water polluting source in which constitutes a threat to human health and ecosystems; due to high water consumption and generated a large volume of color liquid waste. In the present study, the effect of various applied pressure in membrane photocatalytic reactor (MPR) system using ZnO-PEG nanoparticles and polypiperazine amide tight ultrafiltration (UF-PPA) for textile wastewater treatment was systematically investigated mainly through membrane fouling phenomenon. Results showed that the final permeate flux after 180 min was found to increase with the increase of applied pressure which obtained 0.4133 at 6 bar. Under 6 bar of pressure, the dye rejection of permeate was successfully reduced by approximately 100%. The Field Scanning Electron Microscopy (FESEM) analysis was also revealed that 6 bar of applied pressure did not affect or changed the structure of membrane cross-sectional pattern of UF-PPA membrane. In summary, the integrated usage of ZnO-PEG nanoparticles in photocatalysis combined with UF-PPA process improved the membrane fouling phenomenon and able to completely remove the colour from the feed of industrial dye wastewater.