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A New Strategy for Early Evaluations of CO2 Utilization Technologies
- A three-step evaluation procedure based on technology readiness levels helps find the most efficient technology before allocating R&D manpower and investments in CO2 utilization technologies. - Researchers presented a unified framework for early-stage evaluations of a variety of emerging CO2 utilization (CU) technologies. The three-step procedure allows a large number of potential CU technologies to be screened in order to identify the most promising ones, including those at low level of technical maturity, before allocating R&D manpower and investments. When evaluating new technology, various aspects of the new technology should be considered. Its feasibility, efficiency, economic competitiveness, and environmental friendliness are crucial, and its level of technical maturity is also an important component for further consideration. However, most technology evaluation procedures are data-driven, and the amount of reliable data in the early stages of technology development has been often limited. A research team led by Professor Jay Hyung Lee from the Department of Chemical and Biomolecular Engineering at KAIST proposed a new procedure for evaluating the early development stages of emerging CU technologies which are applicable at various technology readiness levels (TRLs). The procedure obtains performance indicators via primary data preparation, secondary data calculation, and performance indicator calculation, and the lead author of the study Dr. Kosan Roh and his colleagues presented a number of databases, methods, and computer-aided tools that can effectively facilitate the procedure. The research team demonstrated the procedure through four case studies involving novel CU technologies of different types and at various TRLs. They confirmed the electrochemical CO2 reduction for the production of ten chemicals, the co-electrolysis of CO2 and water for ethylene production, the direct oxidation of CO2 -based methanol for oxymethylene dimethyl production, and the microalgal biomass co-firing for power generation. The expected range of the performance indicators for low TRL technologies is broader than that for high TRL technologies, however, it is not the case for high TRL technologies as they are already at an optimized state. The research team believes that low TRL technologies will be significantly improved through future R&D until they are commercialized. “We plan to develop a systematic approach for such a comparison to help avoid misguided decision-making,” Professor Lee explained. Professor Lee added, “This procedure allows us to conduct a comprehensive and systematic evaluation of new technology. On top of that, it helps make efficient and reliable assessment possible.” The research team collaborated with Professor Alexander Mitsos, Professor André Bardow, and Professor Matthias Wessling at RWTH Aachen University in Germany. Their findings were reported in Green Chemistry on May 21. This work was supported by the Korea Carbon Capture and Sequestration R&D Center (KCRC). Publications: Roh, K., et al. (2020) ‘Early-stage evaluation of emerging CO2 utilization technologies at low technology readiness levels’ Green Chemistry. Available online at https://doi.org/10.1039/c9gc04440j Profile: Jay Hyung Lee, Ph.D. Professor firstname.lastname@example.org http://lense.kaist.ac.kr/ Laboratory for Energy System Engineering (LENSE) Department of Chemical and Biomolecular Engineering KAIST https://www.kaist.ac.kr Daejeon 34141, Korea (END)
A New Strategy for the Optimal Electroreduction of CO2 to High-Value Products
-Researchers suggest that modulation of local CO2 concentration improves the selectivity, conversion rate, and electrode stability, and shed a new light on the electrochemical CO2 reduction technology for controlling emissions at a low cost.- A KAIST research team presented three novel approaches for modulating local carbon dioxide (CO2) concentration in gas-diffusion electrode (GDE)-based flow electrolyzers. Their study also empirically demonstrated that providing a moderate local CO2 concentration is effective in promoting Carbon–Carbon (C–C) coupling reactions toward the production of multi-carbon molecules. This work, featured in the May 20th issue of Joule, serves as a rational guide to tune CO2 mass transport for the optimal production of valuable multi-carbon products. Amid global efforts to reduce and recycle anthropogenic CO2 emissions, CO2 electrolysis holds great promise for converting CO2 into useful chemicals that were traditionally derived from fossil fuels. Many researches have been attempting to improve the selectivity of CO2 for commercially and industrially high-value multi-carbon products such as ethylene, ethanol, and 1-propanol, due to their high energy density and large market size. In order to achieve the highly-selective conversion of CO2 into valuable multi-carbon products, past studies have focused on the design of catalysts and the tuning of local environment related to pH, cations, and molecular additives. Conventional CO2 electrolytic systems relied heavily on an alkaline electrolyte that is often consumed in large quantities when reacting with CO2, and thus led to an increase in the operational costs. Moreover, the life span of a catalyst electrode was short, due to its inherent chemical reactivity. In their recent study, a group of KAIST researchers led by Professor Jihun Oh from the Department of Materials Science and Engineering reported that the local CO2 concentration has been an overlooked factor that largely affects the selectivity toward multi-carbon products. Professor Oh and his researchers Dr. Ying Chuan Tan, Hakhyeon Song, and Kelvin Berm Lee proposed that there is an intimate relation between local CO2 and multi-carbon product selectivity during electrochemical CO2 reduction reactions. The team employed the mass-transport modeling of a GDE-based flow electrolyzer that utilizes copper oxide (Cu2O) nanoparticles as model catalysts. They then identified and applied three approaches to modulate the local CO2 concentration within a GDE-based electrolytic system, including 1) controlling the catalyst layer structure, 2) CO2 feed concentration, and 3) feed flow rate. Contrary to common intuition, the study showed that providing a maximum CO2 transport leads to suboptimal multi-carbon product faradaic efficiency. Instead, by restricting and providing a moderate local CO2 concentration, C–C coupling can be significantly enhanced. The researchers demonstrated experimentally that the selectivity rate increased from 25.4% to 61.9%, and from 5.9% to 22.6% for the CO2 conversion rate. When a cheap milder near-neutral electrolyte was used, the stability of the CO2 electrolytic system improved to a great extent, allowing over 10 hours of steady selective production of multi-carbon products. Dr. Tan, the lead author of the paper, said, “Our research clearly revealed that the optimization of the local CO2 concentration is the key to maximizing the efficiency of converting CO2 into high-value multi-carbon products.” Professor Oh added, “This finding is expected to deliver new insights to the research community that variables affecting local CO2 concentration are also influential factors in the electrochemical CO2 reduction reaction performance. My colleagues and I hope that our study becomes a cornerstone for related technologies and their industrial applications.” This work was supported by the Korean Ministry of Science and ICT (MSIT) Creative Materials Discovery Program. Publication: Tan, Y. C et al. (2020) ‘Modulating Local CO2 Concentration as a General Strategy for Enhancing C−C Coupling in CO2 Electroreduction’, Joule, Vol. 4, Issue 5, pp. 1104-1120. Available online at https://doi.org/10.1016/j.joule.2020.03.013 Profile: Jihun Oh, PhD Associate Professor email@example.com http://les.kaist.ac.kr/ Laboratory for Energy and Sustainability (LE&S) Department of Materials Science and Engineering (MSE) Korea Advanced Institute of Science and Technology (KAIST) https://www.kaist.ac.kr Daejeon 34141, Republic of Korea Profile: Ying Chuan Tan, PhD firstname.lastname@example.org LE&S, MSE, KAIST Profile: Hakhyeon Song, PhD Candidate email@example.com LE&S, MSE, KAIST Profile: Kelvin Berm Lee, M.S. Candidate firstname.lastname@example.org LE&S, MSE, KAIST (END)
3D Hierarchically Porous Nanostructured Catalyst Helps Efficiently Reduce CO2
- This new catalyst will bring CO2 one step closer to serving as a sustainable energy source. - KAIST researchers developed a three-dimensional (3D) hierarchically porous nanostructured catalyst with carbon dioxide (CO2) to carbon monoxide (CO) conversion rate up to 3.96 times higher than that of conventional nanoporous gold catalysts. This new catalyst helps overcome the existing limitations of the mass transport that has been a major cause of decreases in the CO2 conversion rate, holding a strong promise for the large-scale and cost-effective electrochemical conversion of CO2 into useful chemicals. As CO2 emissions increase and fossil fuels deplete globally, reducing and converting CO2 to clean energy electrochemically has attracted a great deal of attention as a promising technology. Especially due to the fact that the CO2 reduction reaction occurs competitively with hydrogen evolution reactions (HER) at similar redox potentials, the development of an efficient electrocatalyst for selective and robust CO2 reduction reactions has remained a key technological issue. Gold (Au) is one of the most commonly used catalysts in CO2 reduction reactions, but the high cost and scarcity of Au pose obstacles for mass commercial applications. The development of nanostructures has been extensively studied as a potential approach to improving the selectivity for target products and maximizing the number of active stable sites, thus enhancing the energy efficiency. However, the nanopores of the previously reported complex nanostructures were easily blocked by gaseous CO bubbles during aqueous reactions. The CO bubbles hindered mass transport of the reactants through the electrolyte, resulting in low CO2 conversion rates. In the study published in the Proceedings of the National Academy of Sciences of the USA (PNAS) on March 4, a research group at KAIST led by Professor Seokwoo Jeon and Professor Jihun Oh from the Department of Materials Science and Engineering designed a 3D hierarchically porous Au nanostructure with two different sizes of macropores and nanopores. The team used proximity-field nanopatterning (PnP) and electroplating techniques that are effective for fabricating the 3D well-ordered nanostructures. The proposed nanostructure, comprised of interconnected macroporous channels 200 to 300 nanometers (nm) wide and 10 nm nanopores, induces efficient mass transport through the interconnected macroporous channels as well as high selectivity by producing highly active stable sites from numerous nanopores. As a result, its electrodes show a high CO selectivity of 85.8% at a low overpotential of 0.264 V and efficient mass activity that is up to 3.96 times higher than that of de-alloyed nanoporous Au electrodes. “These results are expected to solve the problem of mass transfer in the field of similar electrochemical reactions and can be applied to a wide range of green energy applications for the efficient utilization of electrocatalysts,” said the researchers. This work was supported by the National Research Foundation (NRF) of Korea. Image credit: Professor Seokwoo Jeon and Professor Jihun Oh, KAIST Image usage restrictions: News organizations may use or redistribute this image, with proper attribution, as part of news coverage of this paper only. Publication: Hyun et al. (2020) Hierarchically porous Au nanostructures with interconnected channels for efficient mass transport in electrocatalytic CO2 reduction. Proceedings of the National Academy of Sciences of the USA (PNAS). Available online at https://doi.org/10.1073/pnas.1918837117 Profile: Seokwoo Jeon, PhD Professor email@example.com http://fdml.kaist.ac.kr Department of Materials Science and Engineering (MSE) https://www.kaist.ac.kr Korea Advanced Institute of Science and Technology (KAIST)Daejeon, Republic of Korea Profile: Jihun Oh, PhD Associate Professor firstname.lastname@example.org http://les.kaist.ac.kr Department of Materials Science and Engineering (MSE) Department of Energy, Environment, Water and Sustainability (EEWS) KAIST Profile: Gayea Hyun PhD Candidate email@example.com http://fdml.kaist.ac.kr Flexible Devices and Metamaterials Laboratory (FDML) Department of Materials Science and Engineering (MSE) KAIST Profile: Jun Tae Song, PhD Assistant Professor firstname.lastname@example.org http://www.cstf.kyushu-u.ac.jp/~ishihara-lab/ Department of Applied Chemistry https://www.kyushu-u.ac.jp Kyushu UniversityFukuoka, Japan (END)
New Catalyst Recycles Greenhouse Gases into Fuel and Hydrogen Gas
< Professor Cafer T. Yavuz (left), PhD Candidate Youngdong Song (center), and Researcher Sreerangappa Ramesh (right) > Scientists have taken a major step toward a circular carbon economy by developing a long-lasting, economical catalyst that recycles greenhouse gases into ingredients that can be used in fuel, hydrogen gas, and other chemicals. The results could be revolutionary in the effort to reverse global warming, according to the researchers. The study was published on February 14 in Science. “We set out to develop an effective catalyst that can convert large amounts of the greenhouse gases carbon dioxide and methane without failure,” said Cafer T. Yavuz, paper author and associate professor of chemical and biomolecular engineering and of chemistry at KAIST. The catalyst, made from inexpensive and abundant nickel, magnesium, and molybdenum, initiates and speeds up the rate of reaction that converts carbon dioxide and methane into hydrogen gas. It can work efficiently for more than a month. This conversion is called ‘dry reforming’, where harmful gases, such as carbon dioxide, are processed to produce more useful chemicals that could be refined for use in fuel, plastics, or even pharmaceuticals. It is an effective process, but it previously required rare and expensive metals such as platinum and rhodium to induce a brief and inefficient chemical reaction. Other researchers had previously proposed nickel as a more economical solution, but carbon byproducts would build up and the surface nanoparticles would bind together on the cheaper metal, fundamentally changing the composition and geometry of the catalyst and rendering it useless. “The difficulty arises from the lack of control on scores of active sites over the bulky catalysts surfaces because any refinement procedures attempted also change the nature of the catalyst itself,” Yavuz said. The researchers produced nickel-molybdenum nanoparticles under a reductive environment in the presence of a single crystalline magnesium oxide. As the ingredients were heated under reactive gas, the nanoparticles moved on the pristine crystal surface seeking anchoring points. The resulting activated catalyst sealed its own high-energy active sites and permanently fixed the location of the nanoparticles — meaning that the nickel-based catalyst will not have a carbon build up, nor will the surface particles bind to one another. “It took us almost a year to understand the underlying mechanism,” said first author Youngdong Song, a graduate student in the Department of Chemical and Biomolecular Engineering at KAIST. “Once we studied all the chemical events in detail, we were shocked.” The researchers dubbed the catalyst Nanocatalysts on Single Crystal Edges (NOSCE). The magnesium-oxide nanopowder comes from a finely structured form of magnesium oxide, where the molecules bind continuously to the edge. There are no breaks or defects in the surface, allowing for uniform and predictable reactions. “Our study solves a number of challenges the catalyst community faces,” Yavuz said. “We believe the NOSCE mechanism will improve other inefficient catalytic reactions and provide even further savings of greenhouse gas emissions.” This work was supported, in part, by the Saudi-Aramco-KAIST CO2 Management Center and the National Research Foundation of Korea. Other contributors include Ercan Ozdemir, Sreerangappa Ramesh, Aldiar Adishev, and Saravanan Subramanian, all of whom are affiliated with the Graduate School of Energy, Environment, Water and Sustainability at KAIST; Aadesh Harale, Mohammed Albuali, Bandar Abdullah Fadhel, and Aqil Jamal, all of whom are with the Research and Development Center in Saudi Arabia; and Dohyun Moon and Sun Hee Choi, both of whom are with the Pohang Accelerator Laboratory in Korea. Ozdemir is also affiliated with the Institute of Nanotechnology at the Gebze Technical University in Turkey; Fadhel and Jamal are also affiliated with the Saudi-Armco-KAIST CO2 Management Center in Korea. <Newly developed catalyst that recycles greenhouse gases into ingredients that can be used in fuel, hydrogen gas and other chemicals.> Publication: Song et al. (2020) Dry reforming of methane by stable Ni–Mo nanocatalysts on single-crystalline MgO. Science, Vol. 367, Issue 6479, pp. 777-781. Available online at http://dx.doi.org/10.1126/science.aav2412 Profile: Prof. Cafer T. Yavuz, MA, PhD email@example.com http://yavuz.kaist.ac.kr/ Associate Professor Oxide and Organic Nanomaterials for the Environment (ONE) Laboratory Graduate School of Energy, Environment, Water and Sustainability (EEWS) Korea Advanced Institute of Science and Technology (KAIST) http://kaist.ac.kr Daejeon, Republic of Korea Profile: Youngdong Song firstname.lastname@example.org Ph.D. Candidate Department of Chemical and Biomolecular Engineering Korea Advanced Institute of Science and Technology (KAIST) http://kaist.ac.kr Daejeon, Republic of Korea (END)
KAIST and Saudi Aramco agreed to establish a joint CO2 research center in Korea
The Korea Advanced Institute of Science and Technology (KAIST) and Saudi Aramco, a global energy and petrochemicals enterprise, signed a memorandum of understanding (MOU) on January 6, 2013 in Dhahran, Saudi Arabia and pledged to jointly collaborate in research and development of innovative technologies and solutions to address the world"s energy challenges. Under the MOU, the two entities agreed to establish a research center, Saudi Aramco-KAIST CO2 Research Center, near KAIST"s main campus in Daejeon, Korea. The research center, to be jointly managed by KAIST and Saudi Aramco, will foster and facilitate research collaborations in areas such as tackling carbon dioxide (CO2) emissions by removal or capture of CO2, conversing CO2 into useful products, developing efficiency improvements in energy production, sharing carbon management technologies, establishing exchange programs, and conducting joint projects. According to Saudi Aramco, the company"s collaboration with KAIST is the first partnership established in Asia. Khalid A. Al-Falih, President and CEO of Saudi Aramco, said, "The CO2 Research Center represents a major step in Saudi Aramco"s research and technology strategy to partner with top global institutions to help address and find sustainable solutions to the world’s energy challenge both domestically and internationally."
Launched the Saudi Aramco-KAIST CO2 Management Center in Korea
KAIST and Saudi Aramco, a global energy and petrochemicals enterprise, signed on February 20, 2013 the Master Research and Collaboration Agreement (the Agreement) on joint collaborations in research and development of carbon management between the two entities. The Agreement was subsequently concluded upon the signing of the Memorandum of Understanding (MOU) between KAIST and Saudi Aramco, dated January 7th, 2013. In the Agreement, the two organizations specified terms and conditions necessary to conduct joint research projects and stipulated governing body for the operation of the Saudi Aramco-KAIST CO2 Management Center. KAIST and Saudi Aramco, a national oil company for Saudi Arabia, entered into the MOU, in which the two parties shared a common interest in addressing the issue of CO2 capture, CO2storage, CO2 avoidance using efficiency improvements, and converting CO2 into useful chemicals and other materials, and agreed to “create a major research center for CO2” in Korea. As envisioned by the MOU and its subsequent agreement, KAIST and Saudi Aramco decided to operate an interim office of the Saudi Aramco-KAIST CO2 Management Center at KAIST campus in Daejeon, Korea, pending the establishment of the research center. The full-fledged, independent research facility will be built at a location and during a period to be agreed between the two parties. Following the signing of the Agreement, there was a celebration event taken place, including a signboard hanging ceremony for the interim research office. A 10-member delegation from Saudi Aramco, which was headed by Vice President of Engineering Services Samir Al-Tubayyeb, Dr. Nam-Pyo Suh, former president of KAIST, Vice President of Research at KAIST Kyung-Wook Paik, and senior representatives from Korean oil and petrochemical companies such as S-Oil, Lotte Chemicals, SK Innovation, and STX attended the event. Kyung-Wook Paik, Vice President of Research at KAIST, said, “In order to help find solutions to carbon management, KAIST and Saudi Aramco will facilitate to exchange each party’s complementary technical expertise, gain insight into new research fields, and have access to key sources of talent, while promoting innovation for technology solutions and contributing to the lifelong learning agenda of both organizations.” Samir Al-Tubayyeb, Vice President of Engineering Services at Saudi Aramco, added that “As a world-leading oil and gas company, Saudi Aramco’s mission is to promote the continued use of safe, environmentally-friendly petroleum products with a vision to becoming a global leader in research and technology. Building a strong and cooperative relationship with KAIST in our endeavor to search for alternative ways to better utilization of fossil fuels will expedite the creation of opportunities to make the world environmentally safer and sustainable.” KAIST and Saudi Aramco will each chip in a maximum of USD 5 million annually for the establishment and operation of the Saudi Aramco-KAIST CO2 Management Center during the initial term of the Master Research and Collaboration Agreement, which starts in 2013 and continues through 2018.
A Substance with Amazingly Improved Efficiency of Capturing Carbon Dioxides Developed
From left to right: Prof.Ali Coskun, Prof. Cafer T. Yavuz and Prof. Yousung Jung - Selectivity of CO2 increased by 300 times in comparison to nitrogen, published in Nature Communications- KAIST EEWS graduate school’s joint research team led by Prof. Cafer T. Yavuz, Prof. Ali Coskun, and Prof. Yousung Jung has developed the world"s most efficient CO2 absorbent that has 300 times higher carbon dioxide selectivity in comparison to nitrogen. Recently, the importance of CCS* technology, which is about capturing, storing and treating carbon dioxides, has begun to emerge world-widely as a practical alternative for the response to climate change. * CCS : Carbon Capture and sequestration Current carbon dioxide capturing technologies are wet capturing using liquid absorbent, dry capturing using solid absorbent and separation-membrane capturing using a thin membrane like a film. For the places like power plant and forge, where the emission of carbon dioxides is huge, the main task is to maintain the capturing efficiency under extremely hot and humid conditions. The previously studied dry absorbents, such as MOF or zeolite, had the disadvantages of instability in moist conditions and expensive cost for synthesis. On the other hand, the research team"s newly discovered dry absorbent, named ‘Azo-COP’, can be synthesized without any expensive catalysts so the production cost is very low. It is also stable under hot and humid conditions. COP is a structure consisting of simple organic molecules combined into porous polymer and is the first dry carbon dioxide capturing material developed by this research team. The research team introduced an additional functional group called "Azo" to the substance, so that it can selectively capture carbon dioxides among the mixture of gas. Azo-COP, which includes ‘Azo’ functional group, is manufactured easily by using common synthesis methods, and impurities are removed simply by using cheap solvents like water and acetone instead of expensive catalysts. As a result, the manufacturing cost has lowered drastically. Especially, Azo-COP is combined with carbon dioxides by weak attraction force rather than chemical attraction so the recycling energy cost for the absorbent can be reduced innovatively, and it is expected to be used for capturing substances other than carbon dioxides in various areas as it is stable under extreme conditions even under 350 degrees Celsius. This research is supported by Korea Carbon Capture&Sequestration R&D Center(Head: Sangdo Park) and KAIST EEWS planning group. Prof. Cafer T. Yavuz and Prof. Ali Coskun said that “when Azo-COP is used for separation of CO2 and N2, the capturing efficiency has increased by hundred times.” He continued “This substance does not need any catalysts and has great chemical characteristics like water stability and structure stability so is expected to be used in various fields including carbon dioxides capturing” Meanwhile, this research is published in ‘Nature’s stablemate ‘Nature Communications’ on 15th of Jan.
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