{"id":139164,"date":"2024-02-20T07:35:00","date_gmt":"2024-02-20T06:35:00","guid":{"rendered":"https:\/\/renewable-carbon.eu\/news\/?p=139164"},"modified":"2024-02-16T14:57:06","modified_gmt":"2024-02-16T13:57:06","slug":"capturing-greenhouse-gases-with-the-help-of-light","status":"publish","type":"post","link":"https:\/\/renewable-carbon.eu\/news\/capturing-greenhouse-gases-with-the-help-of-light\/","title":{"rendered":"Capturing greenhouse gases with the help of light"},"content":{"rendered":"\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-large is-resized\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"512\" src=\"https:\/\/renewable-carbon.eu\/news\/media\/2024\/02\/image.imageformat.carousel.2028160280-2-1024x512.jpg\" alt=\"In the new process, air is channelled through a liquid to capture CO2. If the liquid is irradiated with light, the greenhouse gas is released again and can be collected (AI-\u200bgenerated symbol image). \" class=\"wp-image-139171\" style=\"aspect-ratio:2;width:815px;height:auto\" srcset=\"https:\/\/renewable-carbon.eu\/news\/media\/2024\/02\/image.imageformat.carousel.2028160280-2-1024x512.jpg 1024w, https:\/\/renewable-carbon.eu\/news\/media\/2024\/02\/image.imageformat.carousel.2028160280-2-300x150.jpg 300w, https:\/\/renewable-carbon.eu\/news\/media\/2024\/02\/image.imageformat.carousel.2028160280-2-150x75.jpg 150w, https:\/\/renewable-carbon.eu\/news\/media\/2024\/02\/image.imageformat.carousel.2028160280-2-768x384.jpg 768w, https:\/\/renewable-carbon.eu\/news\/media\/2024\/02\/image.imageformat.carousel.2028160280-2-1536x768.jpg 1536w, https:\/\/renewable-carbon.eu\/news\/media\/2024\/02\/image.imageformat.carousel.2028160280-2-2048x1024.jpg 2048w, https:\/\/renewable-carbon.eu\/news\/media\/2024\/02\/image.imageformat.carousel.2028160280-2-400x200.jpg 400w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><figcaption class=\"wp-element-caption\">In the new process, air is channelled through a liquid to capture CO<sub>2<\/sub>. If the liquid is irradiated with light, the greenhouse gas is released again and can be collected (AI-\u200bgenerated symbol image).&nbsp;(Visualisation: ETH Zurich)<\/figcaption><\/figure><\/div>\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Researchers use light-\u200breactive molecules to influence the acidity of a liquid and thereby capture of CO<sub>2<\/sub><\/strong>.<\/li>\n\n\n\n<li><strong>They have developed a special mixture of different solvents to ensure that the light-\u200breactive molecules remain stable over a long period of time.<\/strong><\/li>\n\n\n\n<li><strong>Conventional carbon capture technologies are driven by temperature or pressure differences and require a lot of energy. This is no longer necessary with the new light-\u200bbased process.<\/strong><\/li>\n<\/ul>\n\n\n\n<p><strong>If we want to slow down global warming, we need to drastically reduce greenhouse gas emissions. Among other things, we need to do without fossil fuels and use more energy-\u200b\u200befficient technologies. However, reducing emissions alone won\u2019t do enough to meet the climate targets. We must also capture large quantities of the greenhouse gas CO<sub>2<\/sub>&nbsp;from the atmosphere and either store it permanently underground or use it as a carbon-\u200b\u200bneutral feed material in industry. Unfortunately, the carbon capture technologies available today require a lot of energy and are correspondingly expensive.<\/strong><\/p>\n\n\n\n<p>That\u2019s why researchers at ETH Zurich are developing a new method that uses light. With this process, in the future, the energy required for carbon capture will come from the sun.<a><\/a><\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>Light-\u200bcontrolled acid switch<\/strong><\/h3>\n\n\n\n<p>Led by Maria Lukatskaya, Professor of Electrochemical Energy Systems, the scientists are exploiting the fact that in acidic aqueous liquids, CO<sub>2<\/sub>&nbsp;is present as CO<sub>2<\/sub>, but in alkaline aqueous liquids, it reacts to form salts of carbonic acid, known as carbonates. This chemical reaction is reversible. A liquid\u2019s acidity determines whether it contains CO<sub>2<\/sub>&nbsp;or a carbonate.<\/p>\n\n\n\n<p>To influence the acidity of their liquid, the researchers added molecules, called photoacids, to it that react to light. If such liquid is then irradiated with light, the molecules make it acidic. In the dark, they return to the original state that makes the liquid more alkaline.<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"512\" src=\"https:\/\/renewable-carbon.eu\/news\/media\/2024\/02\/image.imageformat.1286.1031563644-1024x512.jpg\" alt=\"Photoacids and differences between dark and light enable a cyclic process for the capture and release of CO2. \" class=\"wp-image-139170\" srcset=\"https:\/\/renewable-carbon.eu\/news\/media\/2024\/02\/image.imageformat.1286.1031563644-1024x512.jpg 1024w, https:\/\/renewable-carbon.eu\/news\/media\/2024\/02\/image.imageformat.1286.1031563644-300x150.jpg 300w, https:\/\/renewable-carbon.eu\/news\/media\/2024\/02\/image.imageformat.1286.1031563644-150x75.jpg 150w, https:\/\/renewable-carbon.eu\/news\/media\/2024\/02\/image.imageformat.1286.1031563644-768x384.jpg 768w, https:\/\/renewable-carbon.eu\/news\/media\/2024\/02\/image.imageformat.1286.1031563644-1536x768.jpg 1536w, https:\/\/renewable-carbon.eu\/news\/media\/2024\/02\/image.imageformat.1286.1031563644-400x200.jpg 400w, https:\/\/renewable-carbon.eu\/news\/media\/2024\/02\/image.imageformat.1286.1031563644.jpg 1560w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><figcaption class=\"wp-element-caption\">Photoacids and differences between dark and light enable a cyclic process for the capture and release of CO<sub>2<\/sub>.&nbsp;(Scheme: ETH Zurich)<\/figcaption><\/figure><\/div>\n\n\n<p>This is how the ETH researchers\u2019 method works in detail: The researchers separate CO<sub>2<\/sub>&nbsp;from the air by passing the air through a liquid containing photoacids in the dark. Since this liquid is alkaline, the CO<sub>2<\/sub>&nbsp;reacts and forms carbonates. As soon as the salts in the liquid have accumulated to a significant degree, the researchers irradiate the liquid with light. This makes it acidic, and the carbonates transform to CO<sub>2<\/sub>. The CO<sub>2<\/sub>&nbsp;bubbles out of the liquid, just as it does in a bottle of cola, and can be collected in gas tanks. When there is hardly any CO<sub>2<\/sub>&nbsp;left in the liquid, the researchers switch off the light and the cycle starts all over again, with the liquid ready to capture CO<sub>2<\/sub>.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>It all depends on the mixture<\/strong><\/h3>\n\n\n\n<p>In practice, however, there was a problem: the photoacids used are unstable in water. <\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p>\u201cIn the course of our earliest experiments, we realised that the molecules would decompose after one day,\u201d says <strong>Anna de Vrie<\/strong>s, a doctoral student in Lukatskaya\u2019s group and lead author of the study.<\/p>\n<\/blockquote>\n\n\n\n<p>So Lukatskaya, de Vries and their colleagues analysed the decay of the molecule. They solved the problem by running their reaction not in water but in a mixture of water and an organic solvent. The scientists were able to determine the optimum ratio of the two liquids by laboratory experiments and were able to explain their findings thanks to model calculations carried out by researchers from the Sorbonne University in Paris.<a><\/a><\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"alignleft size-full is-resized\"><img loading=\"lazy\" decoding=\"async\" width=\"1000\" height=\"1000\" src=\"https:\/\/renewable-carbon.eu\/news\/media\/2024\/02\/image.imageformat.fullwidth.1663587253-1.jpg\" alt=\"Maria Lukatskaya\" class=\"wp-image-139168\" style=\"aspect-ratio:1;width:145px;height:auto\" srcset=\"https:\/\/renewable-carbon.eu\/news\/media\/2024\/02\/image.imageformat.fullwidth.1663587253-1.jpg 1000w, https:\/\/renewable-carbon.eu\/news\/media\/2024\/02\/image.imageformat.fullwidth.1663587253-1-300x300.jpg 300w, https:\/\/renewable-carbon.eu\/news\/media\/2024\/02\/image.imageformat.fullwidth.1663587253-1-150x150.jpg 150w, https:\/\/renewable-carbon.eu\/news\/media\/2024\/02\/image.imageformat.fullwidth.1663587253-1-768x768.jpg 768w, https:\/\/renewable-carbon.eu\/news\/media\/2024\/02\/image.imageformat.fullwidth.1663587253-1-270x270.jpg 270w\" sizes=\"auto, (max-width: 1000px) 100vw, 1000px\" \/><figcaption class=\"wp-element-caption\">Maria Lukatskaya<\/figcaption><\/figure><\/div>\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p>\u201cOur process doesn\u2019t need any heating, so it requires much less energy.\u201d<\/p>\n<\/blockquote>\n\n\n\n<div style=\"height:10px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<p>For one thing, this mixture enabled them to keep the photoacid molecules stable in the solution for nearly a month. For another, it ensured that light could be used to switch the solution back and forth as required between being acidic and being alkaline. If the researchers were to use the organic solvent without water, the reaction would be irreversible.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>Doing without heating<\/strong><\/h3>\n\n\n\n<p>Other carbon capture processes are cyclical as well. One established method works with filters that collect the CO<sub>2<\/sub>molecules at ambient temperature. To subsequently remove the CO<sub>2<\/sub>&nbsp;from the filters, these have to be heated to around 100 degrees Celsius. However, heating and cooling are energy-\u200bintensive: they account for the major share of the energy required by the filter method. \u201cIn contrast, our process doesn\u2019t need any heating or cooling, so it requires much less energy,\u201d Lukatskaya says. More than that, the ETH researchers\u2019 new method potentially works with sunlight alone.<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p>\u201cAnother interesting aspect of our system is that we can go from alkaline to acidic within seconds and back to alkaline within minutes. That lets us switch between carbon capture and release much more quickly than in a temperature-\u200bdriven system,\u201d <strong>de Vries<\/strong> explains.<\/p>\n<\/blockquote>\n\n\n\n<p>With this study, the researchers have shown that photoacids can be used in the laboratory to capture CO<sub>2<\/sub>. Their next step on the way to market maturity will be to further increase the stability of the photoacid molecules. They also need to investigate the parameters of the entire process to optimise it further.<a><\/a><\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>Reference<\/strong><\/h2>\n\n\n\n<p>de Vries A, Goloviznina K, Reiter M, Slanne M, Lukatskaya MR: Solvation-\u200bTuned Photoacid as a Stable Light-\u200bDriven pH Switch for CO<sub>2<\/sub>&nbsp;Capture and Release, Chemistry of Materials, 20 December 2023, doi:&nbsp;<a href=\"https:\/\/doi.org\/10.1021\/acs.chemmater.3c02435\">external page10.1021\/acs.chemmater.3c02435<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>If we want to slow down global warming, we need to drastically reduce greenhouse gas emissions. Among other things, we need to do without fossil fuels and use more energy-\u200b\u200befficient technologies. However, reducing emissions alone won\u2019t do enough to meet the climate targets. We must also capture large quantities of the greenhouse gas CO2&nbsp;from the [&#8230;]<\/p>\n","protected":false},"author":59,"featured_media":139191,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_seopress_robots_primary_cat":"none","nova_meta_subtitle":"Researchers at ETH Zurich are developing a new method to remove CO2 from the atmosphere. It involves molecules that become acidic when exposed to light. Their new process requires much less energy than conventional technologies","footnotes":""},"categories":[5571],"tags":[10744,21452,10416,12390,10743],"supplier":[277],"class_list":["post-139164","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-co2-based","tag-carboncapture","tag-carbonstorage","tag-circulareconomy","tag-solvents","tag-useco2","supplier-eidgenoessische-technische-hochschule-zuerich-eth-zuerich"],"_links":{"self":[{"href":"https:\/\/renewable-carbon.eu\/news\/wp-json\/wp\/v2\/posts\/139164","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/renewable-carbon.eu\/news\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/renewable-carbon.eu\/news\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/renewable-carbon.eu\/news\/wp-json\/wp\/v2\/users\/59"}],"replies":[{"embeddable":true,"href":"https:\/\/renewable-carbon.eu\/news\/wp-json\/wp\/v2\/comments?post=139164"}],"version-history":[{"count":0,"href":"https:\/\/renewable-carbon.eu\/news\/wp-json\/wp\/v2\/posts\/139164\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/renewable-carbon.eu\/news\/wp-json\/wp\/v2\/media\/139191"}],"wp:attachment":[{"href":"https:\/\/renewable-carbon.eu\/news\/wp-json\/wp\/v2\/media?parent=139164"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/renewable-carbon.eu\/news\/wp-json\/wp\/v2\/categories?post=139164"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/renewable-carbon.eu\/news\/wp-json\/wp\/v2\/tags?post=139164"},{"taxonomy":"supplier","embeddable":true,"href":"https:\/\/renewable-carbon.eu\/news\/wp-json\/wp\/v2\/supplier?post=139164"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}