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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 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)
Efficiently Producing Fatty Acids and Biofuels from Glucose
Researchers have presented a new strategy for efficiently producing fatty acids and biofuels that can transform glucose and oleaginous microorganisms into microbial diesel fuel, with one-step direct fermentative production. The newly developed strain, created by Distinguished Professor Sang Yup Lee and his team, showed the highest efficiency in producing fatty acids and biodiesels ever reported. It will be expected to serve as a new platform to sustainably produce a wide array of fatty acid-based products from glucose and other carbon substrates. Fossil fuels, which have long been energy resources for our daily lives, are now facing serious challenges: depletion of their reserves and their role in global warming. The production of sustainable bio-based renewable energy has emerged as an essential alternative and many studies to replace fossil fuels are underway. One of the representative examples is biodiesel. Currently, it is mainly being produced through the transesterification of vegetable oils or animal fats. The research team engineered oleaginous microorganisms, Rhodococcus opacus, to produce fatty acids and their derivatives that can be used as biodiesel from glucose, one of the most abundant and cheap sugars derived from non-edible biomass. Professor Lee’s team has already engineered Escherichia coli to produce short-chain hydrocarbons, which can be used as gasoline (published in Nature as the cover paper in 2013). However, the production efficiency of the short-chain hydrocarbons using E. coli (0.58 g/L) fell short of the levels required for commercialization. To overcome these issues, the team employed oil-accumulating Rhodococcus opacus as a host strain in this study. First, the team optimized the cultivation conditions of Rhodococcus opacus to maximize the accumulation of oil (triacylglycerol), which serves as a precursor for the biosynthesis of fatty acids and their derivatives. Then, they systematically analyzed the metabolism of the strain and redesigned it to enable higher levels of fatty acids and two kinds of fatty acid-derived biodiesels (fatty acid ethyl esters and long-chain hydrocarbons) to be produced. They found that the resulting strains produced 50.2, 21.3, and 5.2 g/L of fatty acids, fatty acid ethyl esters, and long-chain hydrocarbons, respectively. These are all the highest concentrations ever reported by microbial fermentations. It is expected that these strains can contribute to the future industrialization of microbial-based biodiesel production. “This technology creates fatty acids and biodiesel with high efficiency by utilizing lignocellulose, one of the most abundant resources on the Earth, without depending on fossil fuels and vegetable or animal oils. This will provide new opportunities for oil and petroleum industries, which have long relied on fossil fuels, to turn to sustainable and eco-friendly biotechnologies,” said Professor Lee. This paper titled “Engineering of an oleaginous bacterium for the production of fatty acids and fuels” was published in Nature Chemical Biology on June 17. This work was supported by the Technology Development Program to Solve Climate Changes on Systems Metabolic Engineering for Biorefineries from the Ministry of Science and ICT through the National Research Foundation (NRF) of Korea (NRF-2012M1A2A2026556 and NRF-2012M1A2A2026557). (Figure: Metabolic engineering for the production of free fatty acids (FFAs), fatty acid ethyl esters (FAEEs), and long-chain hydrocarbons (LCHCs) in Rhodococcus opacus PD630. Researchers have presented a new strategy for efficiently producing fatty acids and biofuels that can transform glucose and oleaginous microorganisms into microbial diesel fuel, with one-step direct fermentative production.) # # # Source: Hye Mi Kim, Tong Un Chae, So Young Choi, Won Jun Kim and Sang Yup Lee. Engineering of an oleaginous bacterium for the production of fatty acids and fuels. Nature Chemical Biology ( https://www.nature.com/nchembio/ ) DOI: 10.1038/s41589-019-0295-5 Profile Dr. Sang Yup Lee email@example.com Distinguished Professor at the Department of Chemical and Biomolecular Engineering KAIST
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.”
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
Elsevier Selects a KAIST Graduate's Paper as the Top Cited Papers in 2011-2012
Dr. Myung-Won Seo, a graduate from the Department of Chemical and Bimolecular Engineering at KAIST, published a paper in January 2011 in Chemical Engineering Journal, which was entitled “Solid Circulation and Loop-seal Characteristics of a Dual Circulating Fluidized Bed: Experiments and CFD Simulation.” His paper was selected by Elsevier as the Top Cited Papers of 2011-2012. The Chemical Engineering Journal is a renowned peer-reviewed journal issued by Elsevier. Dr. Seo published another paper, “CFD Simulation with Experiments in a Dual Circulating Fluidized Bed Gasifier,” in January 2012 in Computers & Chemical Engineering, which was also selected as the Most Downloaded Papers in 2012-2013. Dr. Seo graduated with a doctoral degree from KAIST in 2011. He is currently working at the Clean Fuel Laboratory, the Korea Institute of Energy Research, Daejeon, as a researcher. His research areas are coal gasification, upgrading, and liquefaction, as well as energy and chemical production from low-grade fuels such as biomass and wastes.
High Efficiency Bio-butanol production technology developed
KAIST and Korean Company cooperative research team has developed the technology that increases the productivity of bio-butanol to equal that of bio-ethanol and decreases the cost of production. Professor Lee Sang Yeop (Department of Biological-Chemical Engineering) collaborated with GS Caltex and BioFuelChem Ltd. to develop a bio-butanol production process using the system metabolism engineering method that increased the productivity and decreased the production cost. Bio-butanol is being widely regarded as the environmentally friendly next generation energy source that surpasses bio-ethanol. The energy density of bio-butanol is 29.9MJ (mega Joule) per Liter, 48% larger than bio-ethanol (19.6MJ) and comparable to gasoline (32MJ). Bio-butanol is advantageous in that it can be processed from inedible biomass and is therefore unrelated to food crises. Especially because bio-butanol shows similar characteristics especially in its octane rating, enthalpy of vaporization, and air-fuel ratio, it can be used in a gasoline engine. However barriers such as difficulty in gene manipulation of producer bacterium and insufficient information prevented the mass production of bio-butanol. Professor Lee’s team applied the system metabolism engineering method that he had invented to shift the focus to the production pathway of bio-butanol and made a new metabolism model. In the new model the bio-butanol production pathway is divided into the hot channel and the cold channel. The research team focused on improving the efficiency of the hot channel and succeeded in improving the product yield of 49% (compared to theoretical yield) to 87%. The team furthered their research and developed a live bio-butanol collection and removal system with GS Caltex. The collaboration succeeded in producing 585g of butanol using 1.8kg of glucose at a rate of 1.3g per hour, boasting world’s highest concentration, productivity, and rate and improving productivity of fermentation by three fold and decreasing costs by 30%. The result of the research was published in world renowned ‘mBio’ microbiology journal.
International Workshop on EEWS 2010 was held.
On October 7 and 8th at Fusion Hall of KI Building, KAIST, the 2010 International Workshop on EEWS (Energy, Environment, Water, and Sustainability) was held. The third to be held, forty national and international academic professionals including Mark Shannon, professor at University of Illinois at Urbana-Champaign, Domen Kazunari, Tokyo University professor, Dong Sub Kim, CTO of SK Energy and Doyoung Seung, Senior Vice President of GS Caltex, participated at this year’s workshop. In twelve sessions, themes including Artificial Photosynthesis, Wireless Power Transfer, Green Aviation, Safe Nuclear Fuel Reuse, Fuel Cells in Action, LED 2.0, Foundation of Energy-Water Nexus, and Flexible Battery & Solar Cell were presented and discussed. “Through this workshop, current EEWS policy and research progress from different countries and the future of related technologies will be foreseen,” said Jae Kyu Lee, Dean of KAIST EEWS Initiative. “I hope it became an opportunity to create cooperative relationships with leading researchers.” EEWS is a research project conducted by KAIST to solve global issues that mankind faces today such as depletion of energy, environmental pollution, water shortage, and sustainability.
Prof. Woo"s Team Discovers Eco-Friendly Solid-Oxide Fuel Cell System
A KAIST research team led by Prof. Seong-Ihl Woo of the Department of Chemical & Biomolecular Engineering has found a method to use glycerol, a byproduct from the production of biodiesel, as fuel for solid oxide fuel cells (SOFC), university authorities said on Tuesday (Oct. 27). The research finding shows that glycerol can be an environmentally sustainable fuel when it is used for operating SOFCs with internal reforming, instead of hydrogen and methane. The finding was published in the Oct. 14, 2009 online edition of ChemSusChem, a sister journal of Angewandte Chemie, the world"s leading chemistry journal. Biodiesel is an attractive alternative energy source because of its low sulfur content and demand is growing worldwide as oil price soars. Bio-derived glycerol will not contribute to the greenhouse effect and has the potential to contribute to reducing global warming. Currently, glycereol is used as a raw material in the cosmetic, pharmacy, food, and tobacco industries. However, its supply exceeds its demand as the volume of biodiesel production increases. The production of 1 ton of biodiesel produces 0.1 ton of glycerol. Many researchers have investigated various routes for the consumption of surplus glycerol. The research is expected to contribute to sustainable growth by reducing the emissions of carbon dioxide and reusing generated carbon dioxide for the production of biomass. The new method enables manufacturers to use glycerol as a fuel for operating SOFC.
Prof. Lee"s Team Pioneers Biotechnological Production of Chemical Using Renewable Materials
A research team led by Prof. Sang-Yup Lee of the Bio and Brain Engineering Department at KAIST has succeeded in engineering the bacterium E. coli to produce the industrial chemical putrescine, university authorities said on Monday (Aug. 31). Putrescine, a four carbon chain diamine, is an important platform chemical with a wide range of applications for the pharmaceutical, agrochemical and chemical industries. It is currently used to synthesize nylon-4,6, a widely used engineering plastic. The research result, published in the Biotechnology and Bioengineering journal, proviDrdes a renewable alternative to the traditional process using fossil fuels. Currently the production of putrescine on an industrial scale relies on chemical synthesis, which requires non-renewable petrochemicals and expensive catalyst systems. This process is highly toxic and flammable with potentially severe repercussions for both the environment and human health. "For the first time we have developed a metabolically engineered E. coli strain that efficiently produces putrescine," said Professor Lee. "The development of a bio-refinery for chemicals and materials is very important in a world where dependency on fossil fuels is an increasing concern." The team developed a strain of E.coli capable of producing putrescine through metabolic engineering. This is where a cell"s metabolic and regulatory networks are enhanced in order to increase production of a needed material. First the team weakened or deleted competing metabolic pathways within the E. coli strain before deleting pathways which cause putrescine degradation. They also amplified the crucial enzyme Spec C, which converts the chemical ornithine into putrescine. Finally the putrescine exporter, which allows excretion of intracellularly made putrescine, was engineered while a global regulator was engineered to further increase the concentration of putrescine. The final result of this process was an engineered E.coli strain which produced 24.2 g of putrescine per litre. However, as it was believed that putrescine is toxic to microorganisms the team had to study putrescine tolerance in E.coli before it could be engineered to overproduce the chemical to the levels needed for industrial production. The results revealed that E. coli can tolerate at least 0.5 M of putrescine, which is tenfold higher than the usual concentration in the cell. This level of tolerance was an important surprise as it means that E. coli can be engineered to overproduce putrescine to industrially competitive levels. "The previously expected toxicity of putrescine may explain why its microbial production has been overlooked," said Lee. "Now a metabolically engineered E. coli strain has been developed which is capable of efficiently producing putrescine using renewable methods to an industrial level. This metabolic engineering framework should be useful for developing metabolically engineered microorganisms for the efficient production of other chemicals from renewable resources," he added.
Prof. Cho Wins Best Paper Award
KAIST Prof. Nam-Zin Cho of the Department of Nuclear and Quantum Engineering, won the Best Thesis Award in the nuclear reactor physics category at the 2008 Winter Meeting of the American Nuclear Society held on Nov. 9-13 in Reno, Nevada. His paper, entitled "Thermal Feedback Transient Analysis of a Pebble Fuel Based on the Two-Temperature Homogenized Model," was jointly authored by Hwi Yu and Jong-Un Kim under the guidance of Prof. Cho. Prof. Cho was elected a fellow of the American Nuclear Society in 2001 and has served as the deputy editor of the Nuclear Science and Engineering, the research journal of the American Nuclear Society, since 1999.
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