{"id":66647,"date":"2019-09-20T06:59:51","date_gmt":"2019-09-20T04:59:51","guid":{"rendered":"https:\/\/rss.nova-institut.net\/public.php?url=http%3A%2F%2Fwww.biofuelsdigest.com%2Fbdigest%2F2019%2F09%2F09%2Frice-university-researchers-use-co2-to-produce-formic-acid%2F"},"modified":"2019-09-15T18:38:20","modified_gmt":"2019-09-15T16:38:20","slug":"rice-reactor-turns-greenhouse-gas-into-pure-liquid-fuel","status":"publish","type":"post","link":"https:\/\/renewable-carbon.eu\/news\/rice-reactor-turns-greenhouse-gas-into-pure-liquid-fuel\/","title":{"rendered":"Rice reactor turns greenhouse gas into pure liquid fuel"},"content":{"rendered":"

A common greenhouse gas could be repurposed in an efficient and environmentally friendly way with an electrolyzer that uses renewable electricity to produce pure liquid fuels.<\/strong><\/p>\n

\"Rice
Rice postdoctoral researcher Chuan Xia, left, and chemical and biomolecular engineer Haotian Wang adjust their electrocatalysis reactor to produce liquid formic acid from carbon dioxide. Photo by Jeff Fitlow<\/figcaption><\/figure>\n

The catalytic reactor developed by the Rice University lab of chemical and biomolecular engineer Haotian Wang uses carbon dioxide as its feedstock and, in its latest prototype, produces highly purified and high concentrations of formic acid.<\/p>\n

Formic acid produced by traditional carbon dioxide devices needs costly and energy-intensive purification steps, Wang said. The direct production of pure formic acid solutions will help to promote commercial carbon dioxide conversion technologies.<\/p>\n

The method is detailed in Nature Energy.<\/p>\n

Wang, who joined Rice\u2019s Brown School of Engineering in January, and his group pursue technologies that turn greenhouse gases into useful products. In tests, the new electrocatalyst reached an energy conversion efficiency of about 42%. That means nearly half of the electrical energy can be stored in formic acid as liquid fuel.<\/p>\n

\u201cFormic acid is an energy carrier,\u201d Wang said. \u201cIt\u2019s a fuel-cell fuel that can generate electricity and emit carbon dioxide \u2014 which you can grab and recycle again.<\/p>\n

\"This
This schematic shows the electrolyzer developed at Rice to reduce carbon dioxide, a greenhouse gas, to valuable fuels. At left is a catalyst that selects for carbon dioxide and reduces it to a negatively charged formate, which is pulled through a gas diffusion layer (GDL) and the anion exchange membrane (AEM) into the central electrolyte. At the right, an oxygen evolution reaction (OER) catalyst generates positive protons from water and sends them through the cation exchange membrane (CEM). The ions recombine into formic acid or other products that are carried out of the system by deionized (DI) water and gas. Illustration by Chuan Xia and Demin Liu<\/figcaption><\/figure>\n

\u201cIt\u2019s also fundamental in the chemical engineering industry as a feedstock for other chemicals, and a storage material for hydrogen that can hold nearly 1,000 times the energy of the same volume of hydrogen gas, which is difficult to compress,\u201d he said. \u201cThat\u2019s currently a big challenge for hydrogen fuel-cell cars.\u201d<\/p>\n

\"Rice
Rice postdoctoral researcher Chuan Xia, left, and chemical and biomolecular engineer Haotian Wang. Photo by Jeff Fitlow<\/figcaption><\/figure>\n

Two advances made the new device possible, said lead author and Rice postdoctoral researcher Chuan Xia. The first was his development of a robust, two-dimensional bismuth catalyst and the second a solid-state electrolyte that eliminates the need for salt as part of the reaction.<\/p>\n

\u201cBismuth is a very heavy atom, compared to transition metals like copper, iron or cobalt,\u201d Wang said. \u201cIts mobility is much lower, particularly under reaction conditions. So that stabilizes the catalyst.\u201d He noted the reactor is structured to keep water from contacting the catalyst, which also helps preserve it.<\/p>\n

Xia can make the nanomaterials in bulk. \u201cCurrently, people produce catalysts on the milligram or gram scales,\u201d he said. \u201cWe developed a way to produce them at the kilogram scale. That will make our process easier to scale up for industry.\u201d<\/p>\n

The polymer-based solid electrolyte is coated with sulfonic acid ligands to conduct positive charge or amino functional groups to conduct negative ions. \u201cUsually people reduce carbon dioxide in a traditional liquid electrolyte like salty water,\u201d Wang said. \u201cYou want the electricity to be conducted, but pure water electrolyte is too resistant. You need to add salts like sodium chloride or potassium bicarbonate so that ions can move freely in water.<\/p>\n

\u201cBut when you generate formic acid that way, it mixes with the salts,\u201d he said. \u201cFor a majority of applications you have to remove the salts from the end product, which takes a lot of energy and cost. So we employed solid electrolytes that conduct protons and can be made of insoluble polymers or inorganic compounds, eliminating the need for salts.\u201d<\/p>\n

The rate at which water flows through the product chamber determines the concentration of the solution. Slow throughput with the current setup produces a solution that is nearly 30% formic acid by weight, while faster flows allow the concentration to be customized. The researchers expect to achieve higher concentrations from next-generation reactors that accept gas flow to bring out pure formic acid vapors.<\/p>\n

\"An
An electrocatalysis reactor built at Rice recycles carbon dioxide to produce pure liquid fuel solutions using electricity. The scientists behind the invention hope it will become an efficient and profitable way to reuse the greenhouse gas and keep it out of the atmosphere. Photo by Jeff Fitlow<\/figcaption><\/figure>\n

The Rice lab worked with Brookhaven National Laboratory to view the process in progress. \u201cX-ray absorption spectroscopy, a powerful technique available at the Inner Shell Spectroscopy (ISS) beamline at Brookhaven Lab\u2019s National Synchrotron Light Source II, enables us to probe the electronic structure of electrocatalysts in operando \u2014 that is, during the actual chemical process,\u201d said\u00a0co-author Eli\u00a0Stavitski, lead beamline scientist at ISS. \u201cIn this work, we followed bismuth\u2019s oxidation states at different potentials and were able to identify the catalyst\u2019s active state during carbon dioxide reduction.\u201d<\/p>\n

With its current reactor, the lab generated formic acid continuously for 100 hours with negligible degradation of the reactor\u2019s components, including the nanoscale catalysts. Wang suggested the reactor could be easily retooled to produce such higher-value products as acetic acid, ethanol or propanol fuels.<\/p>\n

\u201cThe big picture is that carbon dioxide reduction is very important for its effect on global warming as well as for green chemical synthesis,\u201d Wang said. \u201cIf the electricity comes from renewable sources like the sun or wind, we can create a loop that turns carbon dioxide into something important without emitting more of it.\u201d<\/p>\n

Co-authors are Rice graduate student Peng Zhu; graduate student Qiu Jiang and Husam Alshareef, a professor of material science and engineering, at King Abdullah University of Science and Technology, Saudi Arabia (KAUST); postdoctoral researcher Ying Pan of Harvard University; and staff scientist Wentao Liang of Northeastern University. Wang is the William Marsh Rice Trustee Assistant Professor of Chemical and Biomolecular Engineering. Xia is a J. Evans Attwell-Welch Postdoctoral Fellow at Rice.<\/p>\n

Rice and the U.S. Department of Energy Office of Science User Facilities supported the research.<\/p>\n","protected":false},"excerpt":{"rendered":"

A common greenhouse gas could be repurposed in an efficient and environmentally friendly way with an electrolyzer that uses renewable electricity to produce pure liquid fuels. The catalytic reactor developed by the Rice University lab of chemical and biomolecular engineer Haotian Wang uses carbon dioxide as its feedstock and, in its latest prototype, produces highly […]<\/p>\n","protected":false},"author":3,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_seopress_robots_primary_cat":"","nova_meta_subtitle":"","footnotes":""},"categories":[5572],"tags":[7204,12366,5817],"supplier":[574],"class_list":["post-66647","post","type-post","status-publish","format-standard","hentry","category-bio-based","tag-feedstock","tag-fuels","tag-research","supplier-rice-university-houston"],"_links":{"self":[{"href":"https:\/\/renewable-carbon.eu\/news\/wp-json\/wp\/v2\/posts\/66647","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\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/renewable-carbon.eu\/news\/wp-json\/wp\/v2\/comments?post=66647"}],"version-history":[{"count":0,"href":"https:\/\/renewable-carbon.eu\/news\/wp-json\/wp\/v2\/posts\/66647\/revisions"}],"wp:attachment":[{"href":"https:\/\/renewable-carbon.eu\/news\/wp-json\/wp\/v2\/media?parent=66647"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/renewable-carbon.eu\/news\/wp-json\/wp\/v2\/categories?post=66647"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/renewable-carbon.eu\/news\/wp-json\/wp\/v2\/tags?post=66647"},{"taxonomy":"supplier","embeddable":true,"href":"https:\/\/renewable-carbon.eu\/news\/wp-json\/wp\/v2\/supplier?post=66647"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}