Development of Cellulose Acetate-Polyethylene Glycol-Chitosan Membrane-Embedded TiO2 Nanoparticles for Reverse Osmosis Desalination

Abstract

The clean water crisis in Indonesia has recently increased due to wastewater pollution in groundwater. As an alternative, the use of seawater for clean water needs to be developed, considering that Indonesia has a very abundant area of sea water which is an alternative as a raw material for clean water resources. In this study, we fabricated TiO₂ nanoparticles (NPs) embedded in CA/PEG/Chitosan membranes for seawater desalination. The effect of TiO₂ NPs for high-performance of developed membranes was evaluated by reverse osmosis (RO) method to determine the unique characteristics and performance of membranes material for evaluating seawater desalination process. Preparation of CA/PEG/Chitosan membrane-embedded TiO₂ NPs was evenly dispersed into the CA/PEG/Chitosan membrane interlayer by blending method and printed on a glass surface to obtain a thin film developed membranes. The characterization and performance over developed membranes were evaluated to observe unique characteristic by adding TiO₂ NPs and its high-performance to reject salt content in seawater. Based on these results, the developed membranes were interestingly characterized by using FTIR spectrophotometer shows the presence of functional groups for organic and inorganic bonds such as C = O, -CH₃, NH₂, C-O, -OH, C-H, and Ti–O-Ti. The presence of TiO₂ NPs indicates the attachment of TiO₂ NPs in the membranes. In addition, a scanning electron microscope (SEM) was also confirmed to evaluate the morphological structure of without and CA/PEG/Chitosan-modified TiO₂ type (I) and (II), in which the pore size of CA/PEG/Chitosan is larger than membrane-embedded TiO₂ NPs. Moreover, XRD analysis also confirmed that TiO₂ NPs has shown amorphously structures formed on CA/PEG/Chitosan membrane, in which the TiO₂ NPs crystal size with 0.25 g of 2.87 nm and 0.5 g of 3.05 nm. Determination of seawater desalination and water flux has shown Ca/PEG/Chitosan membrane-modified TiO₂ NPs can increase salt rejection value but reduce membrane water flux value. The highest flux value is 29.4 L/m indicates by CA/PEG/Chitosan membrane, while the salt rejection value is 61.76% from CA/PEG/Chitosan membrane-embedded 0.5 g TiO₂ NPs. This study provides a new idea for preparing highly permeable and seawater desalination membranes of CA/PEG/Chitosan membrane-embedded TiO₂ NPs under the reverse osmosis method for producing clean water resources.