Science
Related: About this forumResearchers Consider Graphene as a Cure for Desalination Woes
The earth harbors about 1.4 billion cubic kilometers of water. Unfortunately, the vast majority of that water comes from the sea and is not potable unless treated by expensive, energy-hungry desalination plants. Those problems stem largely from inefficiency in the way salt ions are separated from water molecules, and the solution, says a team of materials scientists from the Massachusetts Institute of Technology, lies in fundamentally revising that process.
The predominant desalination method todayreverse osmosis (RO)relies on polymer-based membranes to remove salt and requires great pressure to push water through a semipermeable film.The more pressure applied, the higher the cost. The M.I.T. researchers, led by Jeffrey Grossman and David Cohen-Tanugi, propose that films made of graphene could filter out salt without inhibiting the water flow as much. Graphene, a superstrong sheet of carbon that is only one atom thick, has mostly been seen as a material for improving electronics and optical communications.
Reverse osmosis requires less energy than other desalination approachessuch as thermal distillationbut graphene membranes containing nanoscale pores that are more permeable than the polymers currently used would further cut energy requirements, the researchers reported online last month in Nano Letters.
The idea is to discriminate between water molecules and salt ions based on size. "Reverse osmosis uses size exclusion, except it excludes everything," says Grossman, an associate professor of power engineering.
http://www.scientificamerican.com/article.cfm?id=graphene-desalination-water-crisis&WT.mc_id=SA_CAT_TECH_20120717
Gregorian
(23,867 posts)I'm wasting my breath. Full steam ahead! Keep growing!
However, one must admit it's an interesting possibility. And would fix present problems. But still, the easiest, cheapest, no engineering fix is staring us in the face.
MindMover
(5,016 posts)What is your point ...?
ret5hd
(20,563 posts)i'm not a breeder...are you?
ProdigalJunkMail
(12,017 posts)yeah...fuck 'em...they can die...
sp
Gregorian
(23,867 posts)But only a few. And there are many many which aren't going to be addressed, nor even able to be.
I'll admit that my reply was semi-off topic. But I find it hard to resist bringing up what should be a well discussed and debated issue, but is essentially taboo.
MindMover
(5,016 posts)because being obtuse is really exasperating .....