Membranes - Page 8

Researchers at the University of Florida's Department of Mechanical and Aerospace Engineering are developing a graphene-based membrane that aims to improve the process of dialysis treatments and reduce treatment times.

To achieve these goals, the researchers identified two things that needed addressing: the configuration of the membrane, and the material from which it was made. This membrane is based on simplicity, the team said. It is based on something that uses forces of physics, rather than brute force. I made it simple through better understanding and utilizing molecular and nanomaterials self-assembly processes.

Researchers at the National Graphene Institute and School of Chemical Engineering and Analytical Science at The University of Manchester have developed an ultra-thin membrane using graphene-oxide sheets, that were assembled in a way that they were able to completely remove various organic dyes, dissolved in methanol, which were as small as a nanometre. This is exciting as GO membranes were once thought to be permeable only to aqueous solutions, but the researchers developed a new form of graphene oxide membrane that can filter organic solvents.

In the newly developed ultrathin membranes, graphene-oxide sheets are assembled in such a way that pinholes formed during the assembly are interconnected by graphene nanochannels, which produces an atomic-scale sieve allowing the large flow of solvents through the membrane. When used to filter Cognac and whisky, the membrane permitted alcohol to pass through but trapped the larger molecules that gives the whisky its color. Professor Nair, which led the group, said that "the clear whisky smells similar to the original whisky but we are not allowed to drink it in the lab, however it was a funny Friday night experiment!

Researchers at The University of Manchester have fabricated highly sensitive miniaturized pressure sensors using graphene membranes.

The team reported that the new sensor was made possible by developing a way to effectively float a graphene membrane mere nanometers above a silicon chip. When pressure moves this membrane closer to the surface of the chip, the resulting change in capacitance is measured to read out the pressure change. By fabricating thousands of such floating membranes next to each other, a device can be made of exceptionally high sensitivity to pressure changes.

Researchers at the U.S. Army Engineer Research and Development Center (ERDC) are developing a water treatment system based on a mix of graphene oxide and a byproduct made from shrimp shells.

The ERDC team’s breakthrough was the ability to scale the membranes from the inch and a half diameter membranes other labs throughout the world are working on, to sheets stretching up to two feet long with the potential of making them as big as needed.

China-based manufacturer CKCOM has launched an Indiegogo crowdfunding campaign for Alien Earbuds, offering an affordable but high quality alternative to more expensive true wireless earbuds on the market. Alien earbuds feature graphene-enhanced drivers, 4.5-hour playtime, built-in mic for hands-free calling, and multi-touch button for important gestures, and more. The campaign has already reached $15,498 USD at the time of writing, which stand for 77% of the $20,000 (flexible) goal, with a month left to go.

According to the company, the graphene drivers are "lightweight yet sturdy enough to conduct clear highs, crisp mids, and resonant bass". Graphene prevents unwanted sound distortions that come with standard audio drivers. CKCOM defines the Alien earbuds as "the first pair of true wireless earbuds that offer premium features at the lowest price on the market. Alien Earbuds have all of the bases covered: they're perfect for exercising, traveling, and working out".

The European Commission has released an interim review report of the Graphene Flagship project's first year following the two-and-half-year ramp-up phase. The Graphene Flagship was concluded to have achieved most of its objectives and milestones and delivered exceptional results with significant immediate or potential impact. The Graphene Flagship is further commended for focusing its work towards a more industrially oriented initiative with a higher Technology Readiness Level.

The report mentioned several significant results close to commercial exploitation, including work with Airbus to produce aircraft parts made of graphene composites, a motorcycle helmet with a graphene coating, a new viscoelastic graphene-polymer sensor material, perovskite photovoltaic cells with improved stability and a demonstration of tuneable ion sieving using GO membrane for water desalination.

The Smart Filter project received new Innovate UK funding that follows a previous £700,000 project grant awarded in 2015. The previous grant enabled a two-year project by G2O and the Centre for Process Innovation (CPI), focused on transferring and scaling up the water filtration technology from laboratory to industry, ensuring the technology is usable with full quality control.

The technology has since been validated at CPI and the new grant will focus on transferring it to large-scale manufacturing. That will include the use of industrial printing technology to manufacture membranes and validate their performance using prototypes and will involve collaboration with a number of UK partner organizations including chemicals manufacturer William Blythe and CPI.

An international group of researchers, including scientists from Shinshu University in Japan and Penn State’s ATOMIC Center, created a graphene and graphene oxide-based coating for desalination membranes which are said to be more scalable and sturdier than current nanofiltration membrane technologies available.

The result of this creation would hopefully be a filter for clean water solutions, protein separation, wastewater treatment, as well as pharmaceutical and food industry applications. This membrane uses a simple spray-on technology to coat a mixture of graphene oxide and graphene in solution onto a backbone support membrane of polysulfone that is modified with polyvinyl alcohol. The team reports that even in the early stages of the development of the membrane, it can already reject 85% of salt, which is sufficient for agricultural purposes, and 96% of dye molecules.

Ionic Industries recently announced a process for economically mass-producing graphene micro supercapacitors and added that its directors and key personnel have taken direct stakes in the company.

Ionic stated that since it published the positive results on its graphene micro planar supercapacitors 2 years before, the company has been working toward developing a device that not only demonstrates similar performance but can be produced at scale to deliver an economically viable device.

Researchers at the UAE-based Masdar Institute, part of the Khalifa University of Science and Technology, have announced significant progress in their research in the field of optimized graphene-based membranes, which aim to make water filtration and desalination more efficient and sustainable.

The team worked to develop membranes made of layered reduced graphene-oxide sheets that are able to block the passage of salt ions in a membrane-based seawater desalination process. The spacing between the sheets is what ultimately affects the membrane’s efficacy, or its ability to filter impurities like salt ions while still permitting water molecules to pass through. The spaces between sheets must be just right if they are too large and salt ions are not filtered out, and if they too small and even water molecules are unable to penetrate the membrane.