Tag Archives: G2O Water

Graphene and water (G20 Water commentary)

Tim Harper’s, Chief Executive Officer (CEO) of G2O Water, July 13, 2015 commentary was published on Nanotechnology Now. Harper, a longtime figure in the nanotechnology community (formerly CEO of Cientifica, an emerging technologies consultancy and current member of the World Economic Forum, not unexpectedly focused on water,

In the 2015 World Economic Forum’s Global Risks Report survey participants ranked Water Crises as the biggest of all risks, higher than Weapons of Mass Destruction, Interstate Conflict and the Spread of Infectious Diseases (pandemics). Our dependence on the availability of fresh water is well documented, and the United Nations World Water Development Report 2015 highlights a 40% global shortfall between forecast water demand and available supply within the next fifteen years. Agriculture accounts for much of the demand, up to 90% in most of the world’s least-developed countries, and there is a clear relationship between water availability, health, food production and the potential for civil unrest or interstate conflict.

The looming crisis is not limited to water for drinking or agriculture. Heavy metals from urban pollution are finding their way into the aquatic ecosystem, as are drug residues and nitrates from fertilizer use that can result in massive algal blooms. To date, there has been little to stop this accretion of pollutants and in closed systems such as lakes these pollutants are being concentrated with unknown long term effects.

Ten years ago, following discussions with former Israeli Prime Minister Shimon Peres, I organised a conference in Amsterdam called Nanowater to look at how nanotechnology could address global water issues. [emphasis mine] While the meeting raised many interesting points, and many companies proposed potential solutions, there was little subsequent progress.

Rather than a simple mix of one or two contaminants, most real world water can contain hundreds of different materials, and pollutants like heavy metals may be in the form of metal ions that can be removed, but are equally likely to be bound to other larger pieces of organic matter which cannot be simply filtered through nanopores. In fact the biggest obstacle to using nanotechnology in water treatment is the simple fact that small holes are easily blocked, and susceptibility to fouling means that most nanopore membranes quickly become barriers instead of filters.

Fortunately some recent developments in the ‘wonder material’ graphene may change the economics of water. One of the major challenges in the commercialisation of graphene is the ability to create large areas of defect-free material that would be suitable for displays or electronics, and this is a major research topic in Europe where the European Commission is funding graphene research to the tune of a billion euros. …

Tim goes on to describe some graphene-based solutions including a technology developed at the University of South Carolina, which is also mentioned in a July 16, 2015 G20 Water press release,

Fouling of nano/ultrafiltration membranes in oil/water separation is a longstanding issue and a major economic barrier for their widespread adoption. Currently membranes typically show severe fouling, resulting from the strong adhesion of oil on the membrane surface and/or oil penetration inside the membranes. This greatly degrades their performance and shortens service lifetime as well as increasing the energy usage.

G2O™s bio inspired approach uses graphene oxide (GO) for the fabrication of fully-recoverable membranes for high flux, antifouling oil/water separation via functional and structural mimicking of fish scales. The ultra-thin, amphiphilic, water-locking GO coating mimics the thin mucus layer covering fish scales, while the combination of corrugated GO flakes and intrinsic roughness of the porous supports successfully reproduces the hierarchical roughness of fish scales. Cyclic membrane performance evaluation tests revealed circa 100% membrane recovery by facile surface water flushing, establishing their excellent easy-to-recover capability.

The pore sizes can be tuned to specific applications such as water desalination, oil/water separation, storm water treatment and industrial waste water recovery. By varying the GO concentration in water, GO membranes with different thickness can be easily fabricated via a one-time filtration process.
G2O™s patented graphene oxide technology acts as a functional coating for modifying the surface properties of existing filter media resulting in:
Higher pure water flux;
High fouling resistance;
Excellent mechanical strength;
High chemical stability;
Good thermal stability;
Low cost.

We’re going through a water shortage here in Vancouver, Canada after a long spring season which distinguished itself with a lack of rain and the introduction of a heatwave extending into summer. It is by no means equivalent to the situation in many parts of the world but it does give even those of us who are usually waterlogged some insight into what it means when there isn’t enough water.

For more insight into water crises with a special focus on the Middle East (notice Harper mentioned Israel’s former Prime Minister Shimon Peres in his commentary), I have a Feb. 24, 2014 posting (Water desalination to be researched at Oman’s newly opened Nanotechnology Laboratory at Sultan Qaboos University) and a June 25, 2013 post (Nanotechnology-enabled water resource collaboraton between Israel and Chicago).

You can check out the World Economic Forum’s Outlook on the Global Agenda 2015 here.

The Outlook on the Global Agenda 2015 features an analysis of the Top 10 trends which will preoccupy our experts for the next 12-18 months as well as the key challenges facing the world’s regions, an overview of global leadership and governance, and the emerging issues that will define our future.

G20 Water can be found here.