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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 firstname.lastname@example.org 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 email@example.com 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)
Enhanced Natural Gas Storage to Help Reduce Global Warming
< Professor Atilhan (left) and Professor Yavuz (right) > Researchers have designed plastic-based materials that can store natural gas more effectively. These new materials can not only make large-scale, cost-effective, and safe natural gas storage possible, but further hold a strong promise for combating global warming. Natural gas (predominantly methane) is a clean energy alternative. It is stored by compression, liquefaction, or adsorption. Among these, adsorbed natural gas (ANG) storage is a more efficient, cheaper, and safer alternative to conventional compressed natural gas (CNG) and liquefied natural gas (LNG) storage approaches that have drawbacks such as low storage efficiency, high costs, and safety concerns. However, developing adsorptive materials that can more fully exploit the advantages of ANG storage has remained a challenging task. A KAIST research team led by Professor Cafer T. Yavuz from the Graduate School of Energy, Environment, Water, and Sustainability (EEWS), in collaboration with Professor Mert Atilhan’s group from Texas A&M University, synthesized 29 unique porous polymeric structures with inherent flexibility, and tested their methane gas uptake capacity at high pressures. These porous polymers had varying synthetic complexities, porosities, and morphologies, and the researchers subjected each porous polymer to pure methane gas under various conditions to study the ANG performances. Of these 29 distinct chemical structures, COP-150 was particularly noteworthy as it achieved a high deliverable gravimetric methane working capacity when cycled between 5 and 100 bar at 273 K, which is 98% of the total uptake capacity. This result surpassed the target set by the United States Department of Energy (US DOE). COP-150 is the first ever structure to fulfil both the gravimetric and volumetric requirements of the US DOE for successful vehicular use, and the total cost to produce the COP-150 adsorbent was only 1 USD per kilogram. COP-150 can be produced using freely available and easily accessible plastic materials, and moreover, its synthesis takes place at room temperature, open to the air, and no previous purification of the chemicals is required. The pressure-triggered flexible structure of COP-150 is also advantageous in terms of the total working capacity of deliverable methane for real applications. The research team believed that the increased pressure flexes the network structure of COP-150 showing “swelling” behavior, and suggested that the flexibility provides rapid desorption and thermal management, while the hydrophobicity and the nature of the covalently bonded framework allow these promising materials to tolerate harsh conditions. This swelling mechanism of expansion-contraction solves two other major issues, the team noted. Firstly, when using adsorbents based on such a mechanism, unsafe pressure spikes that may occur due to temperature swings can be eliminated. In addition, contamination can also be minimized, since the adsorbent remains contracted when no gas is stored. Professor Yavuz said, “We envision a whole host of new designs and mechanisms to be developed based on our concept. Since natural gas is a much cleaner fuel than coal and petroleum, new developments in this realm will help switching to the use of less polluting fuels.” Professor Atilhan agreed the most important impact of their research is on the environment. “Using natural gas more than coal and petroleum will significantly reduce greenhouse gas emissions. We believe, one day, we might see vehicles equipped with our materials that are run by a cleaner natural gas fuel,” he added. This study, reported in Nature Energy on July 8, was supported by National Research Foundation of Korea (NRF) grants ( NRF-2016R1A2B4011027, NRF-2017M3A7B4042140, and NRF-2017M3A7B4042235). < Suggested chemical structure of COP-150 > < Initial ingredients (left) and final product (right) of COP-150 synthesis > < Comparison of highest reported volumetric working capacities > (END)
Professor Yim Appointed As Associate Editor of Nuclear Technology
Professor Man-Sung Yim from the Department of Nuclear and Quantum Engineering was appointed as the associate editor (for the Asian region) of Nuclear Technology ― a leading international research journal of the American Nuclear Society. Professor Yim will serve his term for three years from May 2019. The American Nuclear Society, established in 1954, is comprised of more than 11,000 global members and aims to advance nuclear science, engineering, and technology while supporting the peaceful and beneficial applications of nuclear energy. Since its first publication in 1971, Nuclear Technology has been a representative journal of the society, reporting state-of-the-art information on all phases of the practical applications of nuclear technology. Professor Yim is being recognized worldwide for his pioneering nuclear education, research, and policy studies in the fields of non-proliferation, safeguards for severe accident management, and waste management. He served as the head professor of the Department of Nuclear and Quantum Engineering and established the Nonproliferation Education and Research Center (NEREC) at KAIST. Professor Yim remarked, “Asia has an important role to play at the forefront of the world’s nuclear research considering that nuclear development is most actively being carried out in the Asian region these days.”
First Korean Member of OceanObs' Organizing Committee
Professor Sung Yong Kim from the Department of Mechanical Engineering became the first Korean to be elected as an organizing committee member of the international conference OceanObs’19’, specializing in the ocean observing field. Professor Kim has been actively engaged in advisory panels, technical committees, and working groups for the North Pacific Marine Science Organization (PICES). Through numerous activities, he was recognized for his professionalism and academic achievements, which led him to be appointed as a member of the organizing committee. The organizing committee is comprised of leading scholars and researchers from 20 countries, and Professor Kim will be the first Korean scientist to participate on the committee. Since 1999, the conference has been held every decade. Global experts specializing in oceanic observation gather to discuss research directions for the next ten years by monitoring physical, biological, and chemical variables in regional, national, and global oceans and applying marine engineering. This year, approximately 20 institutes including NASA’s Jet Propulsion Laboratory (JPL), the National Science Foundation, the National Oceanic and Atmospheric Administration, and the European Space Agency will support funds as well as high-tech equipment to the conference. This year’s conference theme is the governance of global ocean observing systems such as underwater gliders, unmanned vehicles, remote sensing, and observatories. The conference will hold discussions on monitoring technology and information systems to ensure human safety as well as to develop and preserve food resources. Additionally, participants will explore ways to expand observational infrastructures and carry out multidisciplinary approaches. There will also be collaborations with the Global Ocean Observing System (GOOS) and the Partnership for Observation of the Global Oceans (POGO) to organize ocean observing programs and discuss priorities. Finally, they will set a long-term plan for solving major scientific issues, such as climate change, ocean acidification, energy, and marine pollution. Professor Kim said, “Based on the outcomes drawn from the conference, I will carry out research on natural disasters and climate change monitoring by using unmanned observing systems. I will also encourage more multidisciplinary research in this field.”
"Do Not Erect the Wall, But Build the Bridge"
(Mr. Ban gave a lecture on UN and Global Citizenship at KAIST) “People are saying that multilateralism is under threat, but I believe that it has helped others keep away from wars. There are currently invisible walls among countries. But do not erect the wall, build the bridge!” On December 7, KAIST invited one of the most admired people by Korea’s younger generation to give a lecture on UN and Global Citizenship, as the final session of the Global Leaders Lecture Series 2018. He is the 33th Minister of Foreign Affairs and the 8th Secretary-General of the United Nations, Ban Ki-Moon. Mr. Ban is recognized for making significant contributions to world peace and environmental preservation during his term at the UN. Mr. Ban first opened his lecture by explaining his great expectations for KAIST students. “KAIST is one of the outstanding universities that fosters the world’s best scientists and for that I have a great expectations for your role in the era of the Fourth Industrial Revolution. In this rapidly changing society, acquiring global citizenship is most important,” he said. Who are global citizens? According to UNESCO, they are ‘active promoters of more peaceful, tolerant, inclusive, secure and sustainable societies’. He stated that global leaders lacking global citizenship has resulted in so many disputes among countries and concerns for themselves. This concept of global citizenship came to him when he studied abroad in the U.S as a young man and met John F. Kennedy. He said, “It touched my heart although I was young. He (John F. Kennedy) told me that the world leaders were not getting along well. During the hype of the Cold War, national boundaries were meaningless. The question was whether I could help others. He then encouraged me, telling me that I could change it because I was young.” Mr. Ban proposed four required mindsets for global citizenship. The first is to have respect, empathy, and trustworthiness for others. He believes that speaking is the foundation of knowledge, while listening is the foundation of wisdom. Although the concept of philosophy might vary between the East and West, listening to others is very important for gaining respect, empathy, and trustworthiness. The second is to be future-oriented, particularly for scientists who have the potential to change civilization. He encouraged the audience to look to the future by sharing his story about climate change. “During my term, I received strong advice from scientists that led me to prioritize the issue of climate change. I focused on climate change for better living conditions around the world.” He also added, “This cannot be done by one country. We need to all work together to live harmoniously with nature.” Third, having a critical mindset is important, especially for scientists because it helps with solving problems by taking a scientific approach, without missing any of the small things. It is essential for scientists to find out new things, particularly in the era of the Fourth Industrial Revolution and informatization; however, they need to keep in mind how their findings will affect us. For instance, they need to question how robotics will change humans’ living patterns, as well as their role and how it links to humanity. Last but not least, passion, which goes along with compassion, is required for helping others. Ban thinks people without passion are like the walking dead. When pursuing policies, they need to have the passion to drive it. At the same time, they need to have compassion for creating a happier life for everyone. Mr. Ban ended by saying to the students, “You did not lead the era of informatization, but you are the beneficiaries of it. Acquiring global citizenship, you need to think how you can help even out the growth across the globe through the development of science during this era.”
Fast-Charging Lithium-Oxygen Batteries
(Professor Hye Ryung Byon) KAIST researchers have paved the way for fast-charging lithium-oxygen batteries. Professor Hye Ryung Byon from the Department of Chemistry and Professor Yousung Jung from the Graduate School of EEWS led a joint research team to develop lithium-oxygen batteries exhibiting 80% round-trip efficiency even at high charging rates, solving the problem of existing lithium-oxygen batteries which generally showed drastically lower efficiencies when the charge current rate was increased. This study exploits the size and shape lithium peroxide, a discharge product, which is known to cause the very problems mentioned above. In doing so, the researchers have lowered the overpotential, which is the difference between the thermodynamic reversible potential and the measured potential, and simultaneously improved battery efficiency. Of particular interest is the fact that these high-performance lithium-oxygen batteries can be realized without costly catalysts. One remarkable property of lithium-oxygen batteries is that they can accommodate three to five times the energy density of lithium-ion batteries commonly used today. Therefore, lithium-oxygen batteries would render longer driving distance to electric vehicles or drones, which operate on the continued use of electrical power. However, their weakness lies in that, during charge, the lithium peroxide remains undecomposed at low overpotential, resulting in eventually compromising the battery’s overall performance. This is due to the poor ionic and electrical conductivity of lithium peroxide. To tackle this issue, the researchers could form one-dimensional amorphous lithium peroxide nanostructures through the use of a mesoporous carbon electrode, CMK-3. When compared against non-mesoporous electrodes, CMK-3 showed exceptionally lower overpotential, thereby enhancing the round-trip efficiency of lithium-oxygen batteries. The amorphous lithium peroxide produced along the electrode has a small volume and a large surface area contacting electrolyte solution, which is presumably endowed with high conductivity to speed up the charging of the lithium-oxygen batteries. This research underpins the feasibility of overcoming the fundamental limitations of lithium-oxygen batteries even without the addition of expensive catalytic materials, but rather by the re-configuration of the size and shape of the lithium peroxide. The findings of this research were published in Nature Communications on February 14. Figure 1. Transmission electron microscopy (TEM) images Figure 2. Galvanostatic rate capability Figure 3. Density functional calculation and Bader charge analysis
Formation of Burning Ice in Oceanic Clay Rich Sediment Disclosed
(from left: Professor Tae-Hyuk Kwon and PhD candidate Taehyung Park) A KAIST research team has identified the formation of natural gas hydrates, so-called flammable ice, formed in oceans. Professor Tae-Hyuk Kwon from the Department of Civil & Environmental Engineering and his team found that clay minerals in oceanic clay-rich sedimentary deposits promote formation of gas hydrates and proposed the principle of gas hydrate formation in the clayey sedimentary layers. Gas hydrates are ice-like crystalline structures composed of hydrogen-bonded water molecules encapsulating gas molecules. They are also known as burning ice. Their deposits are so huge that they gain attention for alternative energy. Conventionally, it was believed that formation of gas hydrates is limited in clay sedimentary deposits; however, unexpected abundance of natural gas hydrates in oceanic clay-rich sedimentary deposits raised the issue of how they formed. The surfaces of natural clay minerals are negatively charged and, thus, unavoidably generate physicochemical interactions between clay and water. Such clay-water interactions have a critical role in the occurrence of natural gas hydrates in clay-rich sedimentary formations. However, there has been experimental difficulty in analyzing hydrate formation because of the cations contained in clay particles, which balance the clay surface charges. Therefore, clay particles inevitably release the cations when mixed with water, which complicates the interpretation of experimental results. To overcome this limitation, the team polarized water molecules with an electric field and monitored the induction times of water molecules forming gas hydrates. They found that the 10 kV/m of electric field promoted gas hydrate nucleation under certain conditions rather than slowing it down, due to the partial breakage of the hydrogen bonded water clusters and the lowered thermal energy of water molecules. Professor Kwon said, “Through this research, we gained better insight into the origin of gas hydrates occurrence in clay-rich sedimentary deposits. In the near future, we will soon be able to commercially produce methane gas from natural gas hydrate deposits.” This research, led by PhD candidate Taehyung Park, was published online in Environmental Science and Technology on February 3. (doi: 10.1021/acs.est.7b05477) Figure 1. Formation of gas hydrates with water molecules Figure 2. Enhancement and inhibition of gas hydrates
President Shin Shares His Biggest Challenges, Success, and New Mission
President Sung-Chul Shin talks on his biggest challenges, successes, and new mission in an interview with Times Higher Education on June 29. Followings are the full text of the interview. ▶ What are the unique challenges and advantages of being a university in the Asia-Pacific region? Globalization is definitely the biggest challenge. KAIST has made strenuous institutional efforts to address this issue for decades. Globalization is not just about language issues, especially for an Asian university. There are still lingering cultural barriers. However, we are improving and seeing significant progress. Approximately 85 per cent of our classes are being lectured in English, and my ultimate goal is to make KAIST a bilingual campus for a more globalized environment. Speaking of advantages, we can recruit top-quality students from neighboring countries. ▶ What role do universities have in creating social equality? I strongly believe that education is an essential means of empowerment and social mobility. KAIST has diligently promoted policies to help ensure greater diversity, without discriminating against anyone’s talents on the basis of gender, race, or background. We implement an equal opportunity admission system, with special consideration given to the underprivileged, geographically-excluded groups, North Korean refugees, and many other disadvantaged groups. We recruit five percent of our freshmen from these groups under our admission system annually. As for the gender gap, our female student population is now over 25 per cent, and we expect in the very near future the ratio will increase up to 30 percent. However, female faculty ratio stands at around 10 per cent, so we will attempt to double the ratio soon. In addition, we work to emphasize social responsibility to our students. They are a privileged group, so they should be responsible for giving back their knowledge and talents to society in diverse ways. I am very glad that many of our students engage in the social entrepreneurship programs we are running now. That will be fruitful for ensuring social equity as well as making society better. ▶ What is the most important issue affecting your university right now? KAIST has now emerged as a world-class university and one of the most innovative universities in the Asia-Pacific region. However, building on our new reputation as a "world-leading" university remains a big challenge. As the first and top research university in Korea, KAIST has been the gateway to the advancement of science and technology and innovation. We are now responsible for taking the lead in creating new knowledge that will make a global impact. This is the momentum we need to make another quantum leap to become the university which creates the most global value. ▶ There is a great pressure in Korea for young people to get into a “top” university. Is this pressure on school students too great? Traditionally, going to a top school was deemed the ladder to success in life. We went through the economically tough times in which diverse groups of occupations had never existed before. As a result, competition between individuals was incredibly high to get into good school and good company. It is true that such social pressure occupied thoughts of many young students and their parents. In effect, that was also the driving force for achieving Korea’s economic growth in a relatively short period of time. But things are changing now. We are living in a complex global economic environment. The number of new occupations creates new knowledge and new types of jobs. Even more, this new era changed the conventional paradigm of jobs and success. Successful careers take collaboration, and one must seek whom to work with, where you fit, and what you will do and how you can reach your potential. This change of perception has begun to transform the general definition of a successful life. The government and educational institutions are working to reflect new socio-economic trend to maximize students’ creativity and their own uniqueness in many educational institutions. However, strong competition to get into a top university seems to be a universal problem - as is also the case for the Ivy League in the US and many other regions. ▶ South Korean universities have some of the closest links to industry. Is a lot of your job about building relationships with companies rather than focusing on educational issues? The relationship with industry is increasingly significant, and collaboration is very important in Korea. It is a crucial source for securing students’ jobs. On top of that, we get research funding from companies and supply the pipeline of new inventions and innovation for them, in many case through collaboration projects. That could also be interpreted as our reputation of institutional performance through diverse evaluation indicators. From the industry side, we are a very good supplier of high-caliber manpower. Therefore, a solid relationship with industry is key to the creation of added value of knowledge, as well as a critical steppingstone for technology commercialization. Therefore, scaling up the organic relationship with industry is part of our education and research portfolio as well as part of my job as president. ▶ Do you think the main role of universities is to prepare graduates for the world of work? The role of higher education is to educate the future generation and create new knowledge though research. The conventional concept of research and development (R&D) has expanded to R&DB, as it now includes business. Thus, the role of a university is also evolving. Universities should provide diverse opportunities for graduates to prepare them to contribute to society. That will be one of the ways to realize the social responsibility of a university. ▶ If someone else was taking over your role tomorrow, what’s the most useful advice you could give them? When I took the office in March, I made up my mind to serve our students, faculty and staff with all my heart. I would say, inspire your people with leadership that they can emotionally connected with, if possible. In addition, I think only professionalism can make the best professionals. ▶ Who has inspired you during your career? Dr. Kun-Mo Chung, former vice president of KAIST and former minister for science and technology, is my role model and mentor. He is an internationally renowned nuclear engineer and scholar, and successful technocrat who served as the minister for science and technology twice. He still teaches at KAIST in his eighties. I admired his visionary leadership and his successful career as administrator as well as accomplished scholar. After graduating from Seoul National University, he went to Michigan State University. In his early thirties, he came back to Korea as a member of the United States Agency for International Development survey team to conduct the feasibility study for founding KAIST. He wrote the proposal in the Terman Report to the USAID that the establishment of KAIST would be necessary and useful for Korea. With $6 million dollar loan from the agency, he founded KAIST. He is the true innovator, I think. ▶ How do you use data to make sure your university is performing well? We are analyzing the diverse data released from international evaluation institutions such as THE data and Clarivate Analytics, as well as domestic institutions. Through the various indicators of data, we are keen to realize the global standard of our institution and advance our innovation competitiveness at a global level.
2017 Summer Nuclear Nonproliferation Education Program
The Nuclear Nonproliferation Education and Research Center (NEREC) at KAIST announced its 30 scholarship recipients for the 2017 Summer Nuclear Nonproliferation Education Program on April 18. The six-week program, starting from July 10, will be run in Korea, Japan, and China. The program provides young global scholars with focused and challenging nuclear nonproliferation studies. Young scholars will be exposed to diverse science and technology policies and practices concurrently conducted in many countries and the future direction for enhancing nuclear nonproliferation. They will participate in a series of seminars, projects, international conferences, and field trips. Since its launch in 2014, the program has educated 71 young scholars. This year, more than 150 scholars from 37 countries applied for the program, reflecting the growing reputation of the program both at home and abroad. The director of the NEREC, Professor Man-Sung Yim of the Department of Nuclear and Quantum Engineering at KAIST said that young scholars from very prestigious foreign universities have shown strong interest in the program. According to Professor Yim, this year’s recipients are from 26 universities from 16 countries including Harvard University, Oxford University, the National Research Nuclear University of Russia, and the Tokyo Institute of Technology
Adsorbent That Can Selectively Remove Water Contaminants
Professor Cafer T. Yavuz and his team at the Graduate School of Energy, Environment, Water, and Sustainability (EEWS) have developed an adsorbent that can selectively capture soluble organic contaminants in water. This water treatment adsorbent is a fluorine-based nanoporous polymer that can selectively remove water-soluble micromolecules. It has the added advantage of being cheap and easily synthesized, while also being renewable. The results of this research have been published online in Nature Communication on November 10, 2016. The research paper is titled “Charge-specific Size-dependent Separation of Water-soluble Organic Molecules by Fluorinated Nanoporous Networks.” (DOI: 10.1038/ncomms13377) Water pollution is accelerating as a result of global industrial development and warming. As new materials are produced and applied in the agricultural and industrial sectors, the types of contaminants expelled as sewage and waste water are also becoming diverse. Chemicals such as dyes and pesticides can be especially harmful because they are made up of small and highly soluble organic particles that cannot be completely removed during the water treatment process, ultimately ending up in our drinking water. The current conventional water treatment systems utilize processes such as activated carbon, ozonolysis, and reverse osmosis membrane. These processes, however, are designed to remove larger organic molecules with lower solubility, thus removal of very small molecules with high solubility is difficult. In addition, these micromolecules tend to be charged, therefore are less easily separated in aqueous form. The research team aimed to remove these small molecules using a new adsorbent technology. In order to remove aqueous organic molecular contaminants, the team needed an adsorbent that can adsorb micro-sized molecules. It also needed to introduce a chemical function that would allow it to selectively adsorb molecules, and lastly, the adsorbent needed to be structurally stable as it would be used underwater. The team subsequently developed an adsorbent of fluorine-based porous organic polymer that met all the conditions listed above. By controlling the size of the pores, this adsorbent is able to selectively adsorb aqueous micromolecules of less than 1-2 nm in size. In addition, in order to separate specific contaminants, there should be a chemical functionality, such as the ability to strongly interact with the target material. Fluorine, the most electronegative atom, interacts strongly with charged soluble organic molecules. The research team incorporated fluorine into an adsorbent, enabling it to separate charged organic molecules up to 8 times faster than neutral molecules. The adsorbent developed by Professor Yavuz’s team has wide industrial applications. It can be used in batch-adsorption tests, as well as in column separation for size- and charge-specific adsorption. Professor Yavuz stated that “the charge-selective properties displayed by fluorine has the potential to be applied in desalination or water treatment processes using membranes." This paper was first-authored by Dr. Jeehye Byun, and the research was funded by KAIST’s High Risk High Return Program and the Ministry of Science, ICT and Future Planning of Korea’s Mid-Career Researcher Program, as well as its Technology Development Program to Solve Climate Change. Figure 1. Diagram conceptualizing the process of charge- and size-specific separation by the fluorine-based porous polymer adsorbent Figure 2. Difference in absorbance before and after using a porous fluorine polymer column to separate organic molecules Figure 3. Adsorption properties of a fluorine polymer according to the charge and size of organic molecules
Professor Sung Yong Kim Presents a Keynote Speech at the International Ocean Color Science Meeting (IOCS) 2015
Professor Sung Yong Kim of the Mechanical Engineering Department at KAIST delivered a keynote speech at the International Ocean Color Science Meeting (IOCS) 2015 held in San Francisco on June 15-18, 2015. His speech was entitled “Research and Applications Using Sub-mesoscale GOCI (Geostationary Ocean Color Imager) Data.” The IOCS, organized by the International Ocean Color Coordinating Group (IOCCG), is a community consultation meeting providing communication and collaboration between space agencies and the ocean color community, building strong ties among international representatives of the ocean color communities, and providing a forum for discussion and the evolution of community thinking on a range of issues. Professor Kim was recognized for his contribution towards the development of remote exploration of sub-mesoscale processes including eddies, fronts, and environmental fluid dynamics. He also attended the 26th General Assembly of the International Union of Geodesy and Geophysics (IUGG) in Prague, the Czech Republic, on June 22, 2015 and gave a presentation on the sub-mesoscale eddies circulation research.
Professor Sung-Yong Kim Receives the Young Scientist Award
Professor Sung-Yong Kim of the Department of Ocean Systems Engineering at KAIST received the Young Scientist Award for 2014 conferred by the Korean Society of Oceanography (KSO). The award was presented at the KSO’s fall conference that took place on November 6, 2014 at the campus of the Naval Academy of the Republic of Korea in Jinhae. Professor Kim has been recognized for his outstanding research in coastal oceanography and environmental fluid mechanics. His research papers are frequently published in prestigious journals such as the Journal of Geophysical Research-Oceans by the American Geophysical Union.
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