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One of the main challenges in the treatment of industrial wastewater is the removal of oil-in-water emulsions, which are stable and therefore difficult to treat. Bacterial cellulose (BC) has structural characteristics that make it an ideal filtration membrane. Several research projects are underway to develop new materials, both biotechnological and traditional, for use in filter beds. The study examined the potential of a BC membrane filtration system for treating oily industrial wastewaters, an underexplored biomaterial in wastewater treatment. The results demonstrated that BC is highly effective at removing oily contaminants (~99%), reducing the colour and particulate matter of wastewater, as well as eliminating nearly the entire microbiological load (~99%). SEM, MEV, FTIR, XRD, and TGA confirmed the presence of oil in the interior of the membrane after filtration, characteristic peaks of its chemical composition, and a 40% reduction in crystallinity. TGA revealed an increase from three (pre-filtration) to five (post-filtration) stages of thermal degradation, indicating the retention of the contaminant in the BC. The mechanical tests demonstrated that the membrane has a tensile strength of 72.13 ± 8.22 MPa and tolerated elongation of up to 21.11 ± 4.81% prior to tearing. The BC membrane also exhibited excellent flexibility, as it could be folded >100 times at the same point without exhibiting signs of tearing. The BC surpasses traditional methods, such as activated charcoal and effluent treatment stations, in the removal of emulsified oils. The findings demonstrate that BC is promising for the treatment of industrial wastewaters, which is a field that requires continual technological innovations to mitigate the environmental impacts of the oil industry. [ABSTRACT FROM AUTHOR]

The environmental impacts of the exploration and use of petroleum and derivatives in recent decades have led to increasing interest in novel materials and processes for the treatment of oily effluents. Oily emulsions are difficult to manage and, in some cases, require different types of treatment or combined methods for phase separation. Sustainable, versatile, innovative biomaterials, such as bacterial cellulose (BC), have considerable applicability potential in mixture separation methods. In the present study, a cellulose membrane produced by a symbiotic culture of bacteria and yeasts (SCOBY) was investigated with the aim of measuring the characteristics that would enable its use in the treatment of oily wastewater. BC was analyzed through physicochemical characterizations, which demonstrated its porosity (>75%), chemical structure with high cellulose content and a large quantity of intramolecular H bonds, good thermal stability with maximum degradation at temperatures close to 300 °C, high crystallinity (66%), nanofibrils of approximately 84 nm in diameter and mechanical properties that demonstrated tensile strength of up to 65.53 Mpa, stretching of approximately 18.91% and the capacity to support a compression load of around 5 kN with only the loss of free water in its structure. The characteristic data of the membranes were used for the production of a filtering module for oily mixture separation processes. This support was developed with computational fluid dynamics of finite volumes and finite element structural analysis using advanced computer-assisted engineering tools. Lastly, the conceptual, basic project of a low-cost nanofiltration module was obtained; this module could be expanded to the industrial scale, operating with several modules in parallel. [ABSTRACT FROM AUTHOR]