{"id":337557,"date":"2017-04-04T18:59:39","date_gmt":"2017-04-04T10:59:39","guid":{"rendered":"http:\/\/techcrunch.com\/?p=1472349"},"modified":"2017-04-04T18:59:39","modified_gmt":"2017-04-04T10:59:39","slug":"graphene-used-to-sieve-salts-from-seawater","status":"publish","type":"post","link":"https:\/\/people.utm.my\/asmawisham\/graphene-used-to-sieve-salts-from-seawater\/","title":{"rendered":"Graphene used to sieve salts from seawater"},"content":{"rendered":"

<\/p>\n

Scientists continue to explore the potential of graphene<\/a>, aka the one-atom thin\u00a0sheet of bonded carbon atoms that\u00a0was created\u00a0more than a decade ago\u00a0after researchers first peeled a few layers off\u00a0a block of graphite with some\u00a0Scotch Tape \u2014 before going on to refine their technique\u00a0until a sheet just a single atom thick was\u00a0produced.<\/p>\n

The nanomaterial has been posited\u00a0for all sorts of potentially revolutionary uses, from faster<\/a>, thinner and even transparent electronics; to biotech implants<\/a>; to\u00a0better battery capacity<\/a>. Now researchers at the University of Manchester say they have come up with a method for\u00a0controlling the permeation of graphene oxide membranes so they can act as\u00a0a sieve to desalinate seawater.<\/p>\n

By controlling the size of the pores in the membranes the\u00a0team was able to\u00a0prevent common salts passing through the material \u2014 turning seawater into drinking water.<\/p>\n

While graphene has previously been demonstrated for filtering\u00a0small nanoparticles, organic molecules and even large salts, the challenge with common salts found in seawater is their small size. Graphene membranes also swell in size when immersed in water \u2014 meaning smaller sieves were required in order to block these common salts.<\/p>\n

The team at Manchester say they used physical confinement to control the interlayer spacing within graphene laminates immersed in water \u2014 enabling them to\u00a0achieve what they describe as \u201caccurate and tunable ion sieving\u201d, and to provide a sieve size smaller than the\u00a0diameters of hydrated ions.<\/p>\n

And while they found that permeation rates for the membranes decrease exponentially with decreasing sieve size, they also report that\u00a0water transport itself is only \u201cweakly affected\u201d \u2014 meaning the filtered water flows through the membrane relatively quickly; an important factor if the aim is to develop affordable desalination technology.<\/p>\n

As well as potential uses for desalination, the team envisages wider industrial applications for \u201con-demand filtration capable of filtering out ions according to their sizes\u201d. Their research is detailed in a paper<\/a>\u00a0published in the journal Nature Nanotechnology<\/em>.<\/p>\n

Commenting in a statement<\/a>, one of the researchers, Professor Rahul Nair, said: \u201cRealisation of scalable membranes with uniform pore size down to atomic scale is a significant step forward and will open new possibilities for improving the efficiency of desalination technology.<\/p>\n

\u201cThis is the first clear-cut experiment in this regime. We also demonstrate that there are realistic possibilities to scale up the described approach and mass produce graphene-based membranes with required sieve sizes.\u201d<\/p>\n

Scientists\u00a0at the\u00a0university, which houses the\u00a0\u00a361M National Graphene Institute<\/a> research center, have also been looking\u00a0at using\u00a0graphene membranes for gas separation, such as filtering carbon dioxide molecules from power station flue\u00a0gases\u00a0\u2014 hinting at\u00a0a possible\u00a0route\u00a0for enabling economic carbon capture and storage at scale.<\/p>\n","protected":false},"excerpt":{"rendered":"

\"\" Researchers at the University of Manchester have come up with a method for controlling the permeation of graphene oxide membranes — enabling the nanomaterial to act as a sieve to desalinate seawater. Read More<\/a><\/p>\n

\n<\/img><\/a> <\/img><\/a> <\/img><\/a> <\/img><\/a> <\/img><\/a> <\/img><\/a>\n<\/div>\n

\"\"\/ <\/p>\n","protected":false},"author":5817,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_et_pb_use_builder":"","_et_pb_old_content":"","_et_gb_content_width":"","footnotes":""},"categories":[25],"tags":[59,66,26],"class_list":["post-337557","post","type-post","status-publish","format-standard","hentry","category-technology","tag-media","tag-techcrunch","tag-technology"],"_links":{"self":[{"href":"https:\/\/people.utm.my\/asmawisham\/wp-json\/wp\/v2\/posts\/337557","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/people.utm.my\/asmawisham\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/people.utm.my\/asmawisham\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/people.utm.my\/asmawisham\/wp-json\/wp\/v2\/users\/5817"}],"replies":[{"embeddable":true,"href":"https:\/\/people.utm.my\/asmawisham\/wp-json\/wp\/v2\/comments?post=337557"}],"version-history":[{"count":0,"href":"https:\/\/people.utm.my\/asmawisham\/wp-json\/wp\/v2\/posts\/337557\/revisions"}],"wp:attachment":[{"href":"https:\/\/people.utm.my\/asmawisham\/wp-json\/wp\/v2\/media?parent=337557"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/people.utm.my\/asmawisham\/wp-json\/wp\/v2\/categories?post=337557"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/people.utm.my\/asmawisham\/wp-json\/wp\/v2\/tags?post=337557"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}