Evaluation of the Potential of Bacterial Cellulose in the Treatment of Oily Waters

• Published in: Chemical engineering transactions 2019-05, Vol.74
• Main Authors: Cláudio Galdino, Hugo Meira, Thais Souza, Julia Amorim, Fabiola Almeida, Andrea Costa, Leonie Sarubbo
• Format: Article
• Language: English
• ISSN: 2283-9216
• DOI: 10.3303/CET1974053

Cellulose is the most abundant biopolymer on the planet and has a wide range of applications in different industrial sectors. Environmental preservation policies, on the other hand, promote the development of research to replace vegetable cellulose (VC), due to the fact that its production causes several damages to the environment. In this way, bacterial cellulose (BC) appears as a promising alternative to VC, since it differs from its vegetal similar mainly because it presents fibers of a nanometric character against the micrometric of the vegetable, which gives it excellent mechanical properties like greater purity, higher index of crystallinity, higher water absorption power and higher tensile strength. Thus, the present study was carried out for the development of a filter base on the use of BC membrane for the treatment of oily waters. BC membranes were initially produced in an alternative medium based on corn steep liquor (industrial waste) due to the fact that the standard production medium (HS) represents a high cost for the production of BC on an industrial scale, since is formulated with synthetic compounds. Then, wet BC membrane samples were purified and tested as filters for the separation of oily waters with oil concentrations of 10 ppm, 150 ppm and 230 ppm. The experiments were performed in triplicate and showed 100% removal of the oil present in all samples. Variables such as flow rate, filter diameter (25 mm, 50 mm, 110 mm) and production time of the membranes (6 and 10 days) were evaluated in a filtration system constructed in PVC. By showing that the filtration rate increases proportionally to the filter diameter, it decreases from the 6-day membrane to the 10-day membrane. The mean water mass present in both 6 and 10-day BC membranes exceeded 98%. The wet BC membranes presented satisfactory results in the mechanical assays, however the 10-day membrane supported 100% more in strength (N) than the 6-day film. The results obtained in this study showed the potential of this new nontoxic and efficient biodegradable material in the separation of water/oil mixtures generated in industrial environments. Keywords: Bacterial Cellulose, Gluconacetobacter hansenii; Industrial Waste; Filtrating Membranes; Filtration; Oily Water.