Membranes - Page 7

Researchers associated with the Graphene Flagship have reported overcoming the theoretical limiting performance of membranes in gas separation. This collaborative research from CNR, University of Bologna and Graphene-XT has potential applications in hydrogen purification and carbon capture and storage.

The team explains that polymer-based membranes for gas separation have a trade-off between high gas permeability and high gas selectivity, the so-called Robeson upper bound. By combining individual graphene oxide sheets with polymer spacers, in a sandwich style structure, the researchers have been able to overcome this limit, separating gas quickly and efficiently.

Researchers at MIT have developed a method that might enable the production of long rolls of high-quality graphene. The continuous manufacturing process can reportedly produce five centimeters of high-quality graphene per minute. The longest run was nearly four hours, and it generated around 10 meters of continuous graphene.

MIT is referring to the development as the first demonstration of an industrial, scalable method for manufacturing high-quality graphene that is tailored for use in membranes that filter a variety of molecules. These membranes could be used in biological separation or desalination, for example. The researchers drew from the common industrial roll-to-roll approach blended with chemical vapor deposition, a common graphene-fabrication technique.

Hong Kong-based advanced materials company Surwon Technology announced that a version of a new membrane coating it has tested in heavy-duty desalination applications could soon be part of new water filtration products specially-developed for the consumer market.

The ultra-thin, graphene-based coating has reportedly continued to perform well in ongoing controlled tests at various desalination plants on the Chinese mainland and the company says it is convinced the technology can make a substantial contribution to reducing the cost of thermal and reverse osmosis systems.

As part of a national research collaboration, Spanish researchers including the ICN2 have reached a milestone in graphene research, that potentially brings science a step closer to using graphene in filtration and sensing applications.

The researchers have successfully synthesized a graphene membrane with pores whose size, shape and density can be tuned with atomic precision at the nanoscale. Engineering pores at the nanoscale in graphene can change its fundamental properties. It becomes permeable or sieve-like, and this change alone, combined with graphene's intrinsic strength and small dimensions, points to its future use as the most resilient, energy-efficient and selective filter for extremely small substances including greenhouse gases, salts and biomolecules.

An interesting project under the H2020 initiative is GRAPHENART - focused on examining graphene as an anti-fading agent for the protection of artworks. The project, funded at about €150,000, started at October 2017 and will go on until March 2019.

The reasoning behind the project is that fading, yellowing and discoloration are common degradation effects that result from exposure to UV and visible light and oxidizing agents, resulting in the irreversible alteration of the appearance of contemporary artworks. The GRAPHENART project aims to develop innovative, multi-functional graphene-based products (graphene ‘veils’ and inclusions) that provide UV shielding, de-acidification, oxygen and humidity barriers for the protection of old and modern paintings and artworks.

Researchers at UNSW have developed a graphene-based, laboratory-scale filter that can remove more than 99% of the natural organic matter left behind during conventional treatment of drinking water. In a research collaboration with Sydney Water, the team has demonstrated the success of the approach in laboratory tests on filtered water from the Nepean Water Filtration Plant in western Sydney, and is working to scale up the new technology.

"Our advance is to use filters based on graphene an extremely thin form of carbon. No other filtration method has come close to removing 99% of natural organic matter from water at low pressure," the UNSW team said. "Our results indicate that graphene-based membranes could be converted into an alternative new option that could in the future be retrofitted in conventional water treatment plants."

The Department of Energy (DoE) has selected six projects that seek to make carbon capture technology more affordable and reliable for use in coal-fired power plants to receive $17.3 million in federal funding. Among the project is one graphene project.

The Institute of Gas and Technology has been awarded $2.9 million to develop a transformational graphene oxide-based membrane process for post-combustion carbon capture. The project has also secured $750,052 in non-federal funding.

Scientists from the Australian Commonwealth Scientific and Industrial Research Organisation (CSIRO) have used their own type of graphene called "GraphAir" to develop a water filter membrane that is reportedly capable of making water from Sydney Harbor drinkable.

The membrane makes water purification simpler, more effective and quicker, say CSIRO scientists. Conventional water filter membranes used in water purification​ are made from polymers (plastics) and cannot handle a diverse mix of contaminants, they clog or allow contaminants to pass through, so they have to be separated out before the water is filtered, they said. This technology can create clean drinking water, regardless of how dirty it is, in a single step.

Researchers at The University of Manchester have found a new and exciting physical effect in graphene membranes that could be used in devices to artificially mimic photosynthesis.

The new findings demonstrated an increase in the rate at which the material conducts protons when it is simply illuminated with sunlight. The 'photo-proton' effect, as it has been named, could be utilized to design devices able to directly harvest solar energy to produce hydrogen gas, a promising green fuel. It might also be of interest for other applications, such as light-induced water splitting, photo-catalysis and for making new types of highly efficient photodetectors.

Ghostek announced a new graphene-based headphones, the Rapture Wireless Headphones. Ghostek says that the Rapture uses 40 mm graphene drivers to deliver a "Next-Level HD Audio Experience". Other features include Bluetooth 4.1+EDR, aptX Audio Technology, soft protein leather ear cups, a 3.5mm audio jack input, built-in HD microphone and a LED battery status.

Ghostek's Rapture Wireless Headphones will ship on January 22 for $125.