Bacterial Cellulose Membranes for Dye Removal: Adsorption Behavior, Thermodynamics, Regeneration, and Performance in Simulated Wastewater.

Bacterial cellulose is a sustainable biopolymeric material with considerable potential for wastewater treatment due to its nanofibrous structure and abundance of hydroxyl groups. In this study, BC membranes were evaluated as adsorbents for organic dyes, focusing on pH effects, adsorption behavior, and reusability. Adsorption performance was influenced by pH, with significant differences among some conditions; pH 7 was selected for subsequent experiments based on adsorption performance and its practical relevance. Kinetic studies showed rapid initial adsorption followed by a slower approach to equilibrium, while the maximum experimental adsorption capacity for methylene blue (MB) reached 100.15 mg g-1. BC membranes were separately evaluated with MB, crystal violet, and methyl orange in the presence of inorganic salts, showing effective but dye-dependent removal. Reusability tests showed a progressive decline, with a 37.26% loss after five adsorption-desorption cycles. FTIR analysis indicated preservation of the main structural features of BC after adsorption. Hydrogen bonding and electrostatic interactions are proposed as plausible contributors to adsorption. Overall, BC membranes showed promising adsorption performance, although regeneration requires further optimization.