Cellulose-based aerogels for efficient dye sorption and oil-water separation in textile wastewater treatment

The increasing environmental pollution resulting from wastewater generated by the textile industry, which is often contaminated with non-biodegradable dyes and oils, underscores the urgent need for innovative treatment solutions. In this work, we introduce a novel bacterial cellulose (BC)-based aerogel, enhanced with sodium carboxymethyl cellulose (CMC) and polydimethylsiloxane (PDMS), designed for effective dye sorption and oilwater separation. The CMC/BC and PDMS/CMC/BC aerogels, fabricated through a straightforward mixing and freeze-drying process, exhibiting a high porosity of 96 %, a low density of 0.097 g/cm3, and remarkable mechanical strength with a compressive stress of 0.70 MPa at 80 % strain. The CMC/BC aerogel exhibited an exceptional dye sorption capacity of 484 mg/g, achieving a maximum removal rate of 96.80 % within 12 h. This performance aligns closely with the pseudo-second-order kinetic model and the Langmuir isothermal model, suggesting that the sorption process is controlled by chemisorption and occurs as a monolayer. Additionally, the PDMS/CMC/BC-11 aerogel exhibited remarkable oil sorption efficiency, attaining 186.03 g/g for petroleum ether, and effectively separated oil from water within 5 s. These findings highlight the potential of the composite aerogels for applications in environmental remediation and industrial processes.