It is an understatement to say that water is a vital part of our existence. But with the current state of things, will we have enough drinking water to last for generations to come? Greenhouse gases are being emitted into the atmosphere with adverse side effects for our planet. With record droughts happening all around the world, poison-filled water wells, and soaring temperatures clean and natural spring water may soon become obsolete. And so, we are faced with the necessity of finding a solution to this problem quickly.
In response to this issue, many countries have begun to look to the oceans for potable fluids especially with the ever-rising sea level. The existing Reverse Osmosis plants rely heavily upon processes that are energy-intensive and very expensive to operate. However, it is pivotal to desalinate ocean water before we could ever drink it, or bath with it for that matter. So it is a good thing that engineers at Lockheed Martin have just recently announced a newly-developed salt filter that could possibly reduce desalinization energy costs by 99 percent.
The Reverse Osmosis process works on a simple molecular level: molecules found within a liquid will flow across a semipermeable membrane from areas of higher concentration to lower concentration, until both sides finally reach an equilibrium. However, that same membrane can act as a filter for large ions and molecules if outside pressure is enforced to one side of the system. The desalinization process typically employs a sheet of thin-film composite (TFC) membrane, and this membrane is made from an active thin-film layer of polyimide stacked on a porous layer of polysulfone. The main issue with these membranes is that their thickness needs the presence of large amounts of pressure and energy to press water through them.
On the other hand, Lockheed Martin’s Perforene, is made from single atom-thick sheets of graphene. Because these sheets are so thin, water is able to flow through them much easier than through the traditional TFC. Filters made through this Perforene process could incorporate filtering holes only 100 mn in diameter. This is large enough to allow water molecules through but small enough to capture any dissolved salts. It looks thin, but ounce for ounce it’s 1000 times stronger than steel. “It’s 500 times thinner than the best filter on the market today and a thousand times stronger. The energy that’s required and the pressure that’s required to filter salt is approximately 100 times less.” John Stetson ,the Lockheed engineer credited with this invention, explains.
There are currently no announced plans of when this technology will be available to the everyday consumer. But when the time comes that the Perforene process is readily available, it just may turn our impending doom into a glimmer of hope and prosperity. Clean water for all!