Development of Silica-Eggshell Ceramic Membranes for Dye Removal via Forward Osmosis

Water is an essential resource for life on earth and human development. Unfortunately, many hazardous and persistent chemicals, such as polycyclic aromatic hydrocarbons in dyestuff effluent, can degrade ecosystems and threaten the survival of numerous species. For example, Malaysia faces challenges related to air and water pollution, waste management, and health effects caused by textile industrial activities. Therefore, the purpose of this study is to synthesize and characterize a hollow fibre ceramic membrane made of silica-eggshell to remove dye from the solution through forward osmosis. The membranes were fabricated using a phase inversion method. The results from the characterization and filtration processes of the silica-eggshell membranes with different ratios were compared. The ATR-FTIR results indicated the presence of silica and calcium carbonate in the membranes, confirming the completion of the fabrication. The FESEM results also showed that the 1:2 (silica: eggshell) ratio membrane had more active sites compared to the 1:1 (silica: eggshell) ratio membrane. From the forward osmosis results, it was observed that the membrane with a higher eggshell content (1:2 ratio) efficiently filtered the dye, achieving a 65.33% dye removal efficiency with 30 ppm Remazol Brilliant Blue R dye, compared to the 1:1 (silica: eggshell) membrane. The membrane with a 1:2 silica-to-eggshell ratio also showed an increasing trend in dye removal efficiency when reused in the forward osmosis system for approximately 10 minutes. In conclusion, domestic waste, such as eggshells, can be used to fabricate membranes and effectively remove RBBR dye from the solution. Furthermore, eggshells are a natural material, and incorporating them into membrane fabrication reduces the dependence on synthetic or harmful substances, thereby minimizing the environmental impact of the membrane production process.