Influence of Cellulose Acetate Concentration on The Performance of Biopolymer Membranes for Naphthol Dye Removal from Textile Wastewater

Abstract

Membrane technology has continuously advanced as a promising method for treating industrial wastewater, particularly in the textile sector, which generates large volumes of hazardous and toxic effluents. Textile wastewater typically contains high concentrations of complex organic and inorganic pollutants, with dyes being the most persistent and difficult to remove due to their stable aromatic structures. Compared to conventional treatment processes, membrane-based separation offers notable advantages, including lower energy consumption, a smaller footprint, and the ability to separate dissolved contaminants efficiently. In this study, membranes were fabricated via the phase-inversion technique to evaluate their potential for textile wastewater treatment. The membrane preparation involved varying the cellulose acetate (CA) concentration to 13%, 14%, and 15%, while polyethylene glycol (PEG) at 3% was incorporated as an additive to improve pore formation. Acetone was used as the primary solvent during casting. Comprehensive analyses of membrane characteristics—including water uptake, porosity, pure water flux, and dye rejection—were conducted to determine the relationship between polymer concentration and membrane performance. The findings indicate that the membrane with 13% CA exhibited the highest pure water flux, reaching 87.9483 L/m²·h, suggesting greater permeability due to increased pore formation. Conversely, the membrane prepared with 15% CA demonstrated the highest dye rejection, achieving 30.72% for a 20 ppm naphthol dye solution. These results highlight the inherent trade-off between permeability and selectivity: increasing polymer concentration enhances contaminant rejection but reduces membrane flux. The study provides valuable insights for optimizing membrane formulation for textile wastewater treatment applications.