{"id":34191,"date":"2018-10-30T16:15:27","date_gmt":"2018-10-30T10:45:27","guid":{"rendered":"https:\/\/blog.forumias.com\/?p=34191"},"modified":"2018-10-30T16:15:27","modified_gmt":"2018-10-30T10:45:27","slug":"iit-guwahati-uses-superhydrophobic-cotton-to-remove-oil-spill","status":"publish","type":"post","link":"https:\/\/forumias.com\/blog\/iit-guwahati-uses-superhydrophobic-cotton-to-remove-oil-spill\/","title":{"rendered":"IIT Guwahati uses superhydrophobic cotton to remove oil &#8211; spill"},"content":{"rendered":"<p><a href=\"http:\/\/www.thehindu.com\/sci-tech\/science\/iit-guwahati-uses-superhydrophobic-cotton-to-remove-oil-spill\/article19981565.ece?homepage=true\"><span style=\"font-weight: 400;\">IIT Guwahati uses superhydrophobic cotton to remove oil &#8211; spill<\/span><\/a><\/p>\n<p><b>Context<\/b><\/p>\n<p><span style=\"font-weight: 400;\">A team of Researchers at the Indian Institute of Technology (IIT) Guwahati has removing up to <\/span><b>95% of oil-spill of different densities<\/b><span style=\"font-weight: 400;\">, light and heavy oils, repetitively at least 100 times using super hydrophobic (extremely water repelling) medical cotton.<\/span><\/p>\n<p><b>What was the experiment?<\/b><\/p>\n<ul>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">The researchers turned the medical cotton, which is extremely water absorbing, into a super hydrophobic (water contact angle of 157 degrees) material and used it for absorbing oil both in air and under water.<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">The efficacy of absorption is very high, above 2,000 weight percentage for both heavy and light oils.<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">One gram of the super hydrophobic cotton absorbs 20 grams of either heavy or light oils. The results were published in the <\/span><b><i>Journal of Materials Chemistry A.<\/i><\/b><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">The absorbed oil can be recovered through <\/span><b>physical compression<\/b><span style=\"font-weight: 400;\">. The super hydrophobicity remained intact even when the cotton was manually compressed up to 1,000 times and subjected to other physical manipulations.<\/span><\/li>\n<\/ul>\n<p><b>Other characteristics of the experiment<\/b><\/p>\n<ul>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">It has the ability to absorb oil from three complex phases \u2014 light oil that floats in the air\u2013water interface, sediment oil that settles at the bottom as it is heavy, and from water-in-oil emulsion.<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">The super hydrophobic property remains intact even when exposed to <\/span><b>UV light for ten days<\/b><span style=\"font-weight: 400;\">, the material was able to absorb oil from river and sea water, and extremely acidic (pH 1) and alkaline (pH 12) water.<\/span><\/li>\n<\/ul>\n<p><b>Treating emulsions<\/b><\/p>\n<ul>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">The cotton is inherently incompetent of removing <\/span><b>oil from oil-in-water emulsion.<\/b><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">In the case of <\/span><b>oil-in-water emulsion<\/b><span style=\"font-weight: 400;\"> there is very little of oil present and as there is more water present, the super hydrophobic material <\/span><b>does not come in contact with oil<\/b><span style=\"font-weight: 400;\"> and thus it is unable to remove oil efficiently from oil-in-water emulsion.<\/span><\/li>\n<\/ul>\n<p><b>Filtering oil<\/b><\/p>\n<ul>\n<li><b>Selective filtration of oil under water against gravity<\/b><span style=\"font-weight: 400;\"> in the case of heavy oil that has settled at the bottom was achieved.<\/span><\/li>\n<li><span style=\"font-weight: 400;\">To conduct the experiment, the researchers plugged one end of a tube with the super hydrophobic cotton and dips the tube so it comes in contact with the oil.<\/span><\/li>\n<li><span style=\"font-weight: 400;\">Once in contact with the sediment oil, the cotton absorbs the oil and due to hydraulic pressure, the oil gets removed from the cotton and accumulates inside the tube.<\/span><\/li>\n<li><span style=\"font-weight: 400;\">In the case <\/span><b>of gravity-driven filtration<\/b><span style=\"font-weight: 400;\">, heavy oil mixed with water is <\/span><b>poured into a funnel<\/b><span style=\"font-weight: 400;\">, the tip of which is closed with the super hydrophobic cotton. The heavy oil settles to the bottom and comes in contact with the cotton which filters it leaving the water in the funnel.<\/span><\/li>\n<li>This method can be used in industry to remove the oil component from water before letting out the waste water.<\/li>\n<\/ul>\n<p><strong>Cotton processing<\/strong><\/p>\n<ul>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">The hydroxyl group seen in cotton is first modified with branched <\/span><b>poly (ethylenimine (BPEI)<\/b><span style=\"font-weight: 400;\"> to make it functionalized with amine group.<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">A nanocomplex is prepared separately by mixing BPEI with dipentaerythritol pentaacrylate (5Acl) and added to the functionalised cotton.<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">The nanocomplex provides essential topography and makes the cotton chemically reactive, thus making it possible to further optimize the appropriate chemistry of the material.<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">The nanocomplex reacts with amine-based small molecules of choice to make the cotton hydrophobic to varying degrees.<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">The hydrophobicity from hydrophilic can be tuned to super hydrophobic using different amine-containing small molecules<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\"> It is a green synthesis without the use of any catalyst or hazardous material. The process of making super hydrophobic cotton is a simple three-step process and scalable.<\/span><\/li>\n<\/ul>\n<p><b>What is Super hydrophobic coating?<\/b><\/p>\n<ul>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">A <\/span><b>superhydrophobic coating<\/b><span style=\"font-weight: 400;\"> is a nanoscopic surface layer that repels water. Droplets hitting this kind of coating can fully rebound in the shape of column or pancake.<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">In industry, super-hydrophobic coatings are used in ultra-dry surface applications. The coating causes an almost imperceptibly thin layer of air to form on top of a surface.<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Super-hydrophobic coatings are also found in nature; they appear on plant leaves, such as the Lotus leaf, and some insect wings.<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">The coating can be sprayed onto objects to make them waterproof. The spray is anti-corrosive and anti-icing; has cleaning capabilities; and can be used to protect circuits and grids.<\/span><\/li>\n<\/ul>\n<p><b>Use of super hydrophobic coating<\/b><\/p>\n<ul>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Due to the extreme repellence and in some cases bacterial resistance of hydrophobic coatings, there is much enthusiasm<\/span> <span style=\"font-weight: 400;\">for their wide potential uses with surgical tools, medical equipment, textiles, and all sorts of surfaces and substrates.<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">However, the current state of the art for this technology is hindered in terms of the weak durability of the coating making it unsuitable for most applications.<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Newer engineered surface textures on stainless steel are extremely durable and permanently hydrophobic.<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Optically these surfaces appear as a uniform matte surface but microscopically they consist of rounded depressions one to two microns deep over 25% to 50% of the surface. These surfaces are produced for buildings which will never need cleaning.<\/span><\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<p>IIT Guwahati uses superhydrophobic cotton to remove oil &#8211; spill Context A team of Researchers at the Indian Institute of Technology (IIT) Guwahati has removing up to 95% of oil-spill of different densities, light and heavy oils, repetitively at least 100 times using super hydrophobic (extremely water repelling) medical cotton. What was the experiment? The&hellip; <a class=\"more-link\" href=\"https:\/\/forumias.com\/blog\/iit-guwahati-uses-superhydrophobic-cotton-to-remove-oil-spill\/\">Continue reading <span class=\"screen-reader-text\">IIT Guwahati uses superhydrophobic cotton to remove oil &#8211; spill<\/span><\/a><\/p>\n","protected":false},"author":61,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"footnotes":""},"categories":[555],"tags":[],"class_list":["post-34191","post","type-post","status-publish","format-standard","hentry","category-test-1","entry"],"jetpack_featured_media_url":"","views":{"total":0,"cached_at":"","cached_date":1704897060},"jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/forumias.com\/blog\/wp-json\/wp\/v2\/posts\/34191","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/forumias.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/forumias.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/forumias.com\/blog\/wp-json\/wp\/v2\/users\/61"}],"replies":[{"embeddable":true,"href":"https:\/\/forumias.com\/blog\/wp-json\/wp\/v2\/comments?post=34191"}],"version-history":[{"count":0,"href":"https:\/\/forumias.com\/blog\/wp-json\/wp\/v2\/posts\/34191\/revisions"}],"wp:attachment":[{"href":"https:\/\/forumias.com\/blog\/wp-json\/wp\/v2\/media?parent=34191"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/forumias.com\/blog\/wp-json\/wp\/v2\/categories?post=34191"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/forumias.com\/blog\/wp-json\/wp\/v2\/tags?post=34191"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}