Engineers have developed a new technology for the production of filtration membranes from bacterial nanocellulose and graphene, which are able to effectively purify water and have unique antibacterial properties.
Scientists predict that by 2025 half of the world’s population will live in areas with a shortage of drinking water, so researchers are actively engaged in the development of filtering devices. A group of engineers from the Washington University for five years has been looking for a way to create effective antibacterial membranes that do not contain gold or other expensive materials.
The process of forming their new invention begins with the cultivation of Gluconacetobacter Hansenii bacteria, which absorb sugar, form cellulose nanofibers in water. Next, as the structure grows, the team gradually adds a graphene oxide flakes (GO) to it to make a stable and durable membrane. After the material reaches a certain size, it passes a special processing, during which live Gluconacetobacter Hansenii is removed.
When the light enters the finished membrane, graphene oxide begins to produce heat, quickly heating the surrounding water and nanocellulose. In the course of tests on the material, bacteria were bacteria, and then lit its surface. After three minutes of irradiation with light, all harmful microorganisms died. Engineers determined that the membrane is heated to 70 ° C, which leads to the destruction of the cell walls of E. coli bacteria.
The destruction of microorganisms also helps to clean the filter itself, significantly increasing its effectiveness. Researchers say that the process of production of membranes resembles 3D printing using biomaterial. The technology will allow you to enter not only graphene, but any other component in the process of growing the structure.
Scientists recognize that the introduction of the invention into traditional inverse osmosis systems is a challenge. Therefore, they offer a modular system with a spiral winding, which will cover LEDs or nanogenerator using the mechanical energy of the fluid flow for the production of light and heat.
We previously reported on the invention of lasting