Photocatalytic demulsification of oily wastewater by TiO2-magnetite-reduced graphene oxide nanocomposites

• Main Authors: Tan, Ko Shyn, Mohamed Salleh, Waliyuddin, Khe, Cheng Seong, Chong, Fai Kait, Lai, Chin Wei, You, Kok Yeow, Tan, Pi Lin
• Format: Conference or Workshop Item
• Published: 2023
• Subjects: TK Electrical engineering. Electronics Nuclear engineering
• Online Access: http://eprints.utm.my/108095/; http://dx.doi.org/10.1063/5.0115147
• Institution: Universiti Teknologi Malaysia

Emulsified oily wastewater which contain oil-in-water emulsions, produced by polymer flooding are extremely stable because the dissolved polymers absorbed onto oil/water interface and reducing the interfacial tension. Numerous attentions have been given to such pollution control but to remove the residual oil from emulsion for saving energy and protecting the environment continues to be a challenge in petroleum industry. A novel ternary photocatalyst, consisting of magnetite-RGO decorated with TiO2 nanoparticles, TiO2-Fe3O4-RGO nanocomposites was proposed in order to demulsify the polymer stabilized oil-in-water emulsion. Various techniques were employed to characterize TiO2-Fe3O4-RGO nanocomposites. The morphology of TiO2-Fe3O4-RGO nanocomposites was determined by using FESEM. From observation, TiO2 and Fe3O4 particles that deposited on RGO sheets were arbitrary shape. Besides, EDX analysis shows titanium content is more than Fe. From the XRD pattern of TiO2-Fe3O4-RGO nanocomposites, few main peaks were found at 2? = 25.2°, 36.2°, 37.8°, 47.6°, 54.0° and 62.5°, which were similar to the peaks of TiO2 and Fe3O4 particles. The main diffraction patterns for carbon variety characteristic (002) peaks of graphene at 25.9° did not detected, it might be protected by main peaks of anatase TiO2 at 25.2°. From RAMAN analysis, TiO2-Fe3O4-RGO nanocomposites was attributed to disorder carbon (D band) signal in 1359cm-1 and graphite carbon (G band) signal around 1599cm-1. Besides, TiO2-Fe3O4-RGO nanocomposites was indicated specific vibration at 315cm-1, which can be contributed to the presence of anatase phase of TiO2. In FTIR analysis, there are some specified stretching vibrations. The presence of Ti-O-Ti bond stretching at 797cm-1, 781cm-1 and 662cm-1 were attributed to the good distribution of TiO2 on reduced graphene oxide (RGO). From these analyses, TiO2-Fe3O4-RGO nanocomposites was confirmed successfully synthesized. Photocatalytic demulsification of crude oil-in-water emulsion was tested using TiO2-Fe3O4-RGO nanocomposite and demulsification’s efficiency was achieved more than 75%.