Evaluation of Hydrophilic-Coated Ceramic Membranes for Cost-Effective Treatment of Dye-Contaminated Wastewater

Abstract

Rapid urbanization and the Industrial Revolution have resulted in large quantity of wastewater generation. Therefore, there is a need to explore sustainable options to treat and reuse it. This study investigates the removal of Texas dye, an industrial waste, from an aqueous solution using a cost-effective ceramic membrane. The ceramic membrane is manufactured using a mixture of 63 wt% bentonite, 3 wt% cetyltrimethylammonium bromide (CTAB), 2 wt% calcium carbonate, and 32 wt% quartz, and is fabricated using the hydraulic pressing method followed by sintering. The structural and morphological properties of the manufactured membrane are characterized using Scanning Electron Microscopy (SEM) and X-ray Diffraction (XRD). Experiments are conducted using a synthetic dye solution with an initial concentration of 100 mg/L, under a constant operating pressure of 1 psi and a hydraulic retention time of 60 minutes.

A novel hydrophilic surface modification is applied using Moringa oleifera leaf extract and silver nitrate solution. The modified membrane exhibits an improved permeability of 54.4% and an average pore size of 50 nm. The ceramic membrane shows promising removal efficiency of Texas dye. Reusability tests of the manufactured membrane demonstrate stable membrane performance over five continuous filtration cycles. The membranes are cleaned by backwashing, and removal tests are conducted for further nine cycles. The membrane maintains high removal efficiency of Texas dye, as measured in chemical oxygen demand (COD), as well as hardness, during the first five cycles. This research highlights the potential of ceramic membranes for efficient, low-pressure dye removal and wastewater treatment, with enhanced durability and reusability.