Evaluation of fuller's earth clay ceramic membrane in treating raw rubber-processing wastewater

Ceramic membranes are considered more effective for wastewater treatment applications than polymeric membranes because of their excellent resistance to thermal and chemical environments and possess high durability. To avoid the high cost of commercial ceramic membranes, recently, a significant improvement has been accomplished in developing them using low-cost alternative materials and their application in wastewater treatment. This study investigated the performance of an innovative ceramic microfiltration (MF) membrane fabricated with inexpensive Fuller's earth clay in treating the natural raw rubber (ribbed smoked sheet)-processing wastewater. The flat sheet low-cost membrane used in this study was prepared by uniaxial dry pressing route, followed by sintering at 850 °C, and it possessed 39% porosity with 0.176 µm pore size. The wastewater was treated in dead-end filtration mode at different pressures varying from 0.35 to 2 bar and observed the percentage removal of COD, turbidity, and total suspended solids (TSS). Untreated wastewater had a turbidity of 150 NTU, 1200 mg/L TSS, and 10,800 mg/L COD. At a low operating pressure of 0.35 bar, 94% removal of turbidity and total suspended solids was obtained. Also, significant COD removal of 70.4% from wastewater was obtained using the prepared low-cost MF membrane. Finally, the fouling phenomenon during the wastewater treatment was analyzed and it was concluded that it followed the cake filtration model. For future work, cross-flow filtration of wastewater using fabricated Fuller's earth clay ceramic membrane is recommended as it could pave the way forward towards commercialization and wide-scale industrial applications.