The search for novel clean refrigerants remained elusive until the principles of green chemistry and engineering came to the rescue, coupled with artificial intelligence to speed up the process.��

In the 1990s, the hole in the planet’s ozone layer was a pressing global crisis. Research discovered the ozone layer over Antarctica was thinning due to chlorofluorocarbons (CFCs) used globally in aerosols and cooling devices. Once ubiquitous, CFCs were quickly banned during the 1990s and early 2000s because of their harmful environmental impacts, prompting the search for cleaner and more efficient alternatives.

Hydrofluorocarbons were introduced — refrigerants that contain no chlorine and are not harmful to the ozone layer. However, their impact on global warming is significant compared with traditional refrigerants, leading to regulations limiting their use too. Today’s commercially available refrigerants are third-generation refrigerants, but they remain detrimental to the environment, leading to the hunt for fourth-generation refrigerants that are clean, efficient, and safe.��

A team of researchers from Khalifa University and Universita Rovira I Virgili, Spain, has developed a novel integrated approach to evaluate new potential refrigerants using a machine-learning algorithm. The team’s model maps the relationships between molecular descriptors with the molecular parameters required to meet the thermodynamic properties of an efficient and environmentally friendly novel refrigerant.

Prof. Lourdes Vega, Director of the KU Research and Innovation Center on CO2 and Hydrogen (RICH), Ahmad Darwish, and Ismail Alkhatib, chemical engineering PhD candidates, collaborated with Carlos Alba and Dr. Felix Llovell to develop the model, with their results published in the journal

According to the research team, the first two criteria are dependent on refrigerant atomic composition and structure. Discarding those refrigerants unable to meet environmental and safety standards is a simple first layer of screening for the perfect new refrigerant. The third criterion — excellent technical performance — is harder to screen for as it relies on detailed knowledge of the refrigerant’s thermodynamic properties. This is the main hurdle in the commercialization of new refrigerants.

Developing these simulations, however, requires extensive databases of the relevant properties of known substances and too many refrigerants and blends are being developed for these databases to keep up.

“The standard experimental route to obtaining property measurements has ceased to be capable of meeting the rapidly growing number of newly developed refrigerants,” Prof. Vega said. “This has accelerated the need for predictive computational modeling tools for evaluating the thermodynamic behavior of these refrigerants and obtaining the relevant properties required for technical evaluation. Plenty of tools have been developed, but it’s difficult to assess the adequacy of one thermodynamic model over another as all of these models suffer from some limitation or another. We need a singular universal model.”

Integrating machine learning with molecular-modelling approaches has paved the way for a number of applications, including the rational design of new green materials, predicting thermodynamic behavior of complex systems, and accelerating the development of molecular simulations. Prof. Vega and the research team have leveraged this paradigm for their work.

The team’s model predicts the molecular parameters of pure refrigerants and was applied to 18 third- and fourth-generation refrigerants for testing. These 18 refrigerants were chosen for testing because the team already had access to the experimental data needed to train the machine learning algoriths. Additionally, the third-generation refrigerants were those currently used in the market, and the fourth-generation refrigerants had demonstrated potential to serve as sustainable alternatives with excellent environmental performance. Using these refrigerants allowed the team to prove the model could work and demonstrate a step toward a more predictive framework for estimating refrigerant options.

This way, even in the absence of experimental data, the predictive power of the model could assess whether a refrigerant would perform well.

“Of course, our model could be enhanced using larger datasets for training, but that’s the point of the work,” Prof. Vega said. “Our results showcase the potential of this novel integrated approach for the first technical evaluation of newly developed refrigerants, even in the absence of sufficient experimental data. It’s a first step in facilitating the search for green alternatives that meet technical and environmental requirements for fourth-generation refrigerants.”

Jade Sterling
Science Writer
25 July 2022

The post Searching for Sustainable Refrigerants by Bridging Molecular Modeling with Machine Learning appeared first on Khalifa University.

Khalifa University’s Prof. Lourdes Vega was invited to serve as a guest Editor of a special issue of Industrial and Engineering Chemistry Research from the American Chemical Society dedicated to the latest technological developments and innovations that underpin the establishment of a hydrogen economy.

A continued reliance on fossil fuels for energy production is not sustainable, particularly as energy demand continues to rise in parallel to the industrialization of developing countries and world population growth. Not only does reliance on the combustion of fossil fuels result in greenhouse gas emissions detrimental to the environment, it also creates energy security challenges given that oil, coal, and natural gas are geographically concentrated and subject to volatile prices.

As the world seeks more efficient and environmentally-friendly sources of energy, attention has turned to low-carbon hydrogen production and applications. Hydrogen offers a potential decarbonization solution but technical and economic factors stand in its way.

Given this topic’s global relevance, dedicated a to hydrogen and asked two recognized experts from the editorial board to act as guest editors. Prof. Lourdes Vega, Director of the Khalifa University Research and Innovation Center on CO2 and Hydrogen (RICH) and Acting Senior Director of the Petroleum Institute, and Prof. Sandra Kentish, University of Melbourne, were selected and invited to edit this special edition, which included three papers from RICH researchers.

“Governments internationally are reacting to global warming wake-up calls, putting forward new targets and timeframes for decarbonizing industries and societies,” Prof. Vega said. “To achieve these objectives, the policies of most developed countries now include a commitment to hydrogen as a key alternative energy source.”

Hydrogen fuel is a zero-carbon fuel that can be used in fuel cells or internal combustion engines, including buses, passenger cars, and spacecraft. Hydrogen is abundant in enormous quantities on Earth, but not freely. It is bound in water, hydrocarbons, and other organic matter, making efficient extraction of hydrogen one of the main challenges to using it, or one if it’s derivatives, as a fuel or feedstock for other applications.

Hydrogen production is usually classed in terms of color labels: ‘grey’ hydrogen, the most common way of producing hydrogen today, is obtained from methane and water in what it is called steam methane reforming, producing a large amount of CO2 emitted to the atmosphere;�� ‘blue’ hydrogen is produced through the same process, but adding a subsequent process in which CO2 is captured via carbon capture technologies for further utilization or storage; and ‘green’ hydrogen is produced entirely from renewable energy sources used to split water or, via a much less common approach, hydrogen sulfide.

Osahon Osasuyi, Dr. Georgia Basina, Dr. Yasser Al Wahedi, Dr. Mohammad Abu Zahra, Dr. Giovanni Palmisano, and Dr. Khalid Al-Ali, all from ����’s Department of Chemical Engineering and members of the RICH Center, a toxic byproduct of the oil and gas industry. While many studies have examined the potential of the process experimentally, there is a lack of comprehensive research into how to select the appropriate metal for the thermochemical splitting process. In this paper, 17 metals were shortlisted, with six found to be promising candidates with high efficiency and high hydrogen yield.

Once produced, hydrogen can be used in many of the same applications as natural gas, except it produces no carbon or methane emissions when combusted.

“Hydrogen can help to decarbonize the economy and to reach a net zero emissions goal in a variety of ways,” Prof. Vega said. “In addition to providing a viable solution for energy storage from intermittent renewable energy, hydrogen is also seen as a key source of combined heat and power to replace natural gas and for transport, particularly in difficult to abate sectors such as heavy vehicles, trains, and shipping, since it can offer a zero-emission alternative to fossil fuels.”

“However, there is clearly a long way to go before any country can claim to be a hydrogen economy. Making this energy transition is not an easy task for any nation. The price of renewable energy must decrease to make green hydrogen competitive; new distribution networks, refueling stations and transport pathways must be developed to carry hydrogen to the final destination; and equipment and infrastructure must be adapted. These changes are not straightforward.”

Once hydrogen has been produced, it needs to be stored and transported. Hydrogen has extremely low volumetric energy density, meaning effective hydrogen storage must usually be done at very high pressures or low temperatures to reduce the volume. Unfortunately, compression for storage or transport can consume 20 percent of the energy of the hydrogen itself.

����’s Dr. Anish Varghese, Dr. Suresh Kumar Reddy, and Dr. Georgios Karanikolos, from the RICH Center and the Department of Chemical Engineering,, which are porous and easily tunable to adsorb hydrogen for storage. The team developed a metal-organic framework using copper and graphene oxide for hydrogen storage at ambient temperature, which could be more practical compared to traditional cryogenic conditions.

For hydrogen transport, leakage from infrastructure through valves and other fittings is a significant safety and economic concern. Hydrogen is an extremely small molecule, which means it is difficult to retain, and it also readily forms atomic radicals when in contact with steel and other metals, which puts infrastructure at risk of embrittlement and ultimately, failure. One option is to blend hydrogen into existing natural gas networks as studies suggest these pipelines can handle a blend of up to 30 percent hydrogen before embrittlement becomes a concern.

����’s Dr. Ismail Alkhatib, Dr. Ahmed AlHajaj, Prof. Ali Almansoori and Prof. Vega, all Department of Chemical Engineering,. Despite the attractiveness of hydrogen blending, it’s important to know just how much hydrogen can be included in natural gas pipelines without jeopardizing the safety and operation of the existing pipeline grid. The team also quantifies the effect of hydrogen concentration in the properties of natural gas, with changes noted in the density and speed of sound in particular. This knowledge will help not only for transportation, but also for the utilization of hydrogen blends to replace natural gas, as a way of decarbonizing the industry.

“We hope that readers find these articles of interest,” Prof. Vega said. “Only through the concerted effort of many scientists and engineers can we drive the hydrogen economy further and advance action against climate change.”

Jade Sterling
Science Writer
24 May 2022

The post The Hydrogen Economy: Special Journal Issue Edited by Khalifa University Expert appeared first on Khalifa University.

The American Institute of Chemical Engineers (AIChE) is a leading organization of chemical engineering professionals with more than 60,000 members from more than 110 countries.

Dr. Lourdes F. Vega, Professor of Chemical Engineering and Director of Khalifa University’s Research and Innovation Center on CO2 and Hydrogen (RICH), has been elected as a new fellow of the American Institute of Chemical Engineers (AIChE), the highest grade of membership of the institute. AIChE Fellows, nominated by peers and elected by the board of Directors, are prominent members recognized for their significant service to the profession and contributions to the industry.��

Dr. Vega is an internationally recognized leading authority in the field of molecular thermodynamics, clean energy, and sustainability. She has also integrated molecular modeling and simulations with process modeling and optimization—developing a holistic approach for process design, with recent applications in CO2 capture, hydrogen production, water treatment, and sustainable cooling systems.��

This is a new recognition of her work in the area of clean energy and sustainable products, for which she received the Mohammed Bin Rashid Medal of Scientific Distinguishment in 2020.��

Aside from her accomplishments in research, Dr. Vega is a member of the Mohammed Bin Rashid Academy of Sciences (MBRAS) and the Emirates Scientists Council where she leads the Engineering and Technology Advisory Board.��

“I am very honored with this election. Being recognized by peers is very rewarding. Thanks to all my colleagues and collaborators who led to this achievement, without you it would have been impossible!”��

Ara Maj Cruz
Creative Writer
29 March 2022

The post AIChE Elects Dr. Lourdes Vega as New Fellow appeared first on Khalifa University.

Dr. Vega is also appointed to lead the newly formed Engineering and Technology Advisory Board.

Khalifa University’s Dr. Lourdes Vega now joins the prestigious Emirates Scientists Council (ESC) as a new member. Since its establishment in 2016, the Council has been working in transitioning the UAE from knowledge user to knowledge developer, positioning the country as a destination conducive to scientific research and innovation.����

“I feel very honored and excited to be a member of the Emirates Scientists Council (ESC). As members of the ESC, our duties include, among others, suggesting policies that would create a stimulating environment for innovation and research in order to attract and retain a generation of scientists in various fields, providing scientific advice to the Council of Ministers when required, raising nationally and internationally awareness above the science and technology developed in the country, and effectively establishing collaborations between the public and private sectors to make an impact in the economy and well-being of the country,” Dr. Vega commented about her appointment.��

“Hence, being a member of the Council comes with a great honor and responsibility, as it implies being fully engaged in such an important endeavor. I deeply thank HE Sarah Al Amiri and the Council of Ministers, for allowing me to be an active part of the present and future knowledge-based economy and society of the Country, while contributing to attract the next generation of talented scientists and engineers to be part of the joint effort,” she said.��

Aside from being a new member of the ESC, Dr. Vega is also leading the ESC Advisory Board on Engineering and Technology. The Board was created to support and advise the federal government in matters related to science and technology research and policy to further advance in this direction.��

“It is clear that research and innovation in engineering and technology has already played a key role in the advancement of the Country, and it is expected to have a huge impact in the development of the society of knowledge the Emirates is building, and our quality of life. The Board, led by myself as a member of the ESC, is integrated by a selected team of scientists and experts in their specific fields of science from different universities and institutions in the Emirates, which will work together to accomplish our mandate,” she explained.��

The Board and the Council will work hand in hand in developing the engineering and technology talent pool in the UAE. Part of this is to develop programs to entice the younger generation to become engineers and entrepreneurs. The Board will also actively promote collaborations between public and private research institutions focused on engineering and technology. Describing further the Board’s role and objectives, Dr. Vega said: “We want institutions to go beyond and above individual achievements. Part of our role is to also highlight, nationally and internationally, the impact engineering and technology research and innovation developed here in the Emirates has on the economy and the society.�� As a Board, we will propose and develop different initiatives in all these areas, including mapping the current capabilities and interests aligned with the needs of the country, successful stories, international practices, different collaborations, etc. This is a very exciting task where many scientists and engineers in the Emirates can also contribute.”

Dr. Vega is a Professor of Chemical Engineering and the Director of the Research and Innovation Center on CO2 and Hydrogen (RICH) at Khalifa University. She is an internationally recognized leading authority in her field of molecular thermodynamics, clean energy, and sustainability, now focused on hydrogen production and uses, CO2 capture and utilization at large scale, alternative fuels and sustainable cooling systems. Aside from her new appointment as member of the ESC, Dr. Vega is also a member of the Mohammed Bin Rashid Academy of Sciences (MBRAS). In 2020, she was recognized for her work and expertise in sustainability and clean energy and was awarded the Mohammed bin Rashid Medal for Scientific Distinguishment.��

“As mentioned, I feel very honored for being a member of the Emirates Scientist Council; I came to the Emirates several years ago with the goal to leverage my expertise and knowledge in science and technology for the needs of the country. The dream has come true; now I have an additional responsibility to do it from above, which I am happy to take. Serving is my goal. Paraphrasing the great scientist Isaac Newton, ‘If I have seen further it is by standing on the shoulders of giants’.”

Dr. Vega added, “Being a KU faculty and a member of the ESC reinforces how the country values our knowledge, skills and impact. I would like to remind the KU community that as an institution we have the honor and the responsibility to contribute to the knowledge-based society the country is building, and the role of each of us is equally important to accomplish it. In spite of the difficulties that we may find in our daily tasks, the efforts are worth, as any scientific or technological achievement, big or small, is part of our contribution to the present and future of the country. The better we work together, the higher the impact we can achieve as an institution. In addition, as an educational organization, we are very lucky to have the opportunity to help young talented scientists and engineers to follow their dreams.”

Ara Maj Cruz
Creative Writer
13 January 2022

The post Dr. Lourdes Vega Joins Emirates Scientists Council as New Member appeared first on Khalifa University.

Robust, cost-effective and energy efficient methods to capture carbon dioxide from the atmosphere are made possible with novel materials like porous organic frameworks

Reducing greenhouse gas emissions, particularly carbon dioxide, is paramount in combating climate change. One way to do this is to capture the carbon dioxide (CO₂) emissions directly from the source before they enter the atmosphere.

Dr. Georgios Karanikolos, Associate Professor of Chemical Engineering, Dr. Vengatesan Rangaraj, Research Scientist, and Dr. K. Suresh Kumar Reddy, Research Scientist, designed and developed a new material for use in carbon capture. The properties and efficacy of their phosphazene-core Covalent Triazine Framework were examined and tested at various conditions, with their results published in.

“Carbon dioxide is the primary cause of global warming, which has had adverse effects on climate change in the last few decades and with even more negative consequences predicted for the near future,” Dr. Karanikolos said. “Combusting fossil fuels increases atmospheric CO₂ levels, and since fossil fuels are currently the predominant energy source for industry and the transportation sector, it is essential that we explore robust, and cost- and energy-efficient methods to capture the CO₂ emitted from combustion.”

Carbon capture, utilization and storage (CCUS) is the most widely accepted and promising strategy currently in use, and can be further developed to improve efficiency, energy consumption, and cost.

Successful carbon capture needs a sorbent material that will selectively grab CO₂ in a stream of gas and then readily release it when desired so that the material can be reused, while the released CO₂ can be utilized or sent for long-term storage.

In adsorption, CO₂ reversibly collects in the pores in the material that serve as active capture sites. When, for instance, temperature is lowered, CO₂ adheres to the surface, and when temperature is raised, CO₂ is released. Changes in pressure can also bring about these capture and release cycles.

Currently, aqueous amine solutions, which are solutions containing water and organic compounds called amines that contain nitrogen atoms attached to hydrogen and carbon atoms, are used to capture CO₂ in industrial applications. Amine solutions are excellent at trapping the CO₂, making them the most popular and developed carbon capture technology. However, their disadvantage�� is that in order to recover the trapped CO₂ from the amine solution, the solution has to be heated, requiring large amounts of thermal energy and resulting in some amines being lost to the environment in this high-energy process.

To overcome the shortcomings of amine solutions, solid sorbent materials are a viable alternative. Solid sorbents can selectively adsorb CO₂, however some solid sorbent materials perform better than others. The KU research team focuses on investigating a variety of solid sorbents including zeolites, porous carbon nanostructures, metal-organic frameworks (MOFs), and porous organic frameworks (POFs).

“Over the last few years, MOFs and POFs have been studied extensively for various applications due to their superior textural properties, high structural flexibility and the various functional groups they can contain,” Dr. Karanikolos said. “However, MOFs typically possess low thermal and chemical stability, restricting their use especially in harsh environments. On the other hand, POFs are made of organic building blocks closely connected through covalent bonds that enhance chemical and thermal stability. This means they can be used in environments where MOFs are not suitable.”

Covalent Triazine Frameworks (CTFs) are a class of porous organic frameworks with properties that can be tuned through careful design for a wide range of applications. One such application is carbon dioxide adsorption. CTFs are easily manufactured and can be designed to include functionalities that are CO₂-philic, meaning they can selectively attract the CO₂ from the atmosphere to adsorb into the CTF for removal. CTFs can also include elements such as sulfur, phosphorous, boron, and oxygen to improve the chemical properties of the framework, which can be highly advantageous for CO₂ adsorption.

The KU research team designed and manufactured phosphonitrilic core CTFs (Pz-CTFs) and tested CO₂ adsorption, selectivity, and regeneration at various temperatures and pressures. These CTFs used a phosphorus-based core with a nitrile group to increase crosslinking, which created a material with a high porosity and surface area (one gram of the material has about 1,000 square meters of surface area), providing a large space for CO₂ adsorption.

High surface area, low density, excellent thermal and chemical stability and a large number of nitrogen functional groups make Pz-CTFs excellent potential candidates for CO₂ capture. The team’s Pz-CTFs can work in temperatures up to 500 °C, meaning they can be used in various industries that require high temperatures. Even at these high temperatures, the team’s material exhibited excellent CO₂ uptake. Furthermore, the material does exhibit significant hydrophobic character, meaning it is less impacted by the presence of water in a CO2-containing mixture, it is selective in the presence of other gas species, and it can be reused. Hence, it is a high-capacity and reversible adsorbent for selective carbon capture in extreme environments.

Jade Sterling
Science Writer
29 December 2021

The post An Efficient and Cost-effective New Material for Capturing Carbon Dioxide Emissions appeared first on Khalifa University.

A team of researchers from Khalifa University asks: Are we missing something when evaluating adsorbents for CO2 capture at the system level?

We may be on the brink of global-scale change in the way we consume hydrocarbon fuels, but until the policies and agreements made at COP26 in Glasgow this month can be actualized, our relentless fossil fuel consumption continues to pump carbon dioxide into the atmosphere. These continuous emissions are the leading cause of climate change and it’s clearer than ever that we need to do something about the levels of carbon in our atmosphere.

In 2015, the international community adopted the Paris Climate Agreement, agreeing to limit the global average rise in temperature this century to less than 2° C, compared to pre-industrial levels, but with ambitions to limit the rise to less than 1.5° C. Along with a paradigm shift from fossil fuels to renewable energy sources, deployment of carbon capture, utilization and storage technologies was proposed as a core strategy to actively and significantly reduce greenhouse gas emissions. This is in addition to the clear economic benefit that could be derived from using CO2 as a feedstock material for chemical products in a resilient circular economy.

This means that carbon capture and storage technologies can be implemented across a range of industries from heating to electricity generation. To remove existing carbon dioxide from the atmosphere, we can use chemical solvents of different types, including membranes that adsorb carbon dioxide into porous molecules such as potassium hydroxide. However, this technology is currently expensive and energy intensive, as the amount of CO2 in the atmosphere is much diluted. Alternatively, CO2 capture from concentrated sources such as power plants is expected to play an important role in avoiding CO2 emissions, contributing to climate change mitigation. The more mature technology used in industry today for this purpose is absorption with chemical solvents.

Absorption works well but there’s a trade-off: many of our existing solvents come with an energy cost associated with heating the water for the removal of the CO2 to recover them. Ideally, we need processes that require less energy to capture and separate the CO2.

Dr. Ahmed AlHajaj, Assistant Professor, Hammed Balogun, Research Engineer, Dr. Daniel Bahamon, Research Scientist, Saeed Almenhali, Master student, and Prof. Lourdes Vega, all from the Khalifa University Research and Innovation Center on CO2 and Hydrogen (RICH), developed a systematic tool uses various key performance indicators such as energy consumption and cost to screen novel adsorbents operating at a commercial scale, while maintaining the US Department of Energy requirements of 95 percent CO2 purity and 90 percent CO2 capture rate. They published their results in the prestigious journal.

“There have been many previous attempts to assess the technical performance of adsorbents using experimental and modelling approaches,” Dr. AlHajaj explained. “Ours goes further by considering non-monetized factors including the purity of the captured CO2 as well as the quantity captured, and the energy required for the whole process at commercial scale.”

The team used molecular simulations to generate missing experimental data on the efficacy of the adsorptive material – how much it could adsorb – and a dynamic process model to simultaneously determine its economic potential.

Then, they selected the five most promising candidates for the detailed assessment at industrial carbon capture conditions. These five materials included a zeolite, three metal organic frameworks (MOFs), and activated carbon, all of which were evaluated for capturing CO2 from the flue gas of an industrial coal-fired power plant. The materials were examined for their performance in terms of CO2 purity, CO2 capture rate, productivity, energy consumption, and unit cost of CO2 captured at a commercial scale.

Flue gas is the by-product gas that leaves a fossil fuel power plant via a chimney known as a flue. While its composition depends on the fuel being burned, it mostly comprises nitrogen, carbon dioxide, water vapor and a number of pollutants such as particulate matter, carbon monoxide, nitrogen oxides and sulfur oxides. The ‘smoke’ seen pouring from these flues is not smoke at all, but the water vapor in the gas forming a cloud as it meets cooler air. Carbon dioxide is the second largest component of flue gas at around four to 25 percent, depending on the fuel source. It is sent to the atmosphere unless a carbon capture unit is used to separate it from the flue gas.

“Since the performance of a process can be altered when we scale it up, it was essential to evaluate these materials at commercial and industrial scales,” Prof. Vega said. “The zeolite was included as a comparison as it is already widely used in industry for air separation, where CO2 needs to be removed as an impurity. While one particular MOF performed as well as the traditional zeolite, the zeolite was still the best performing low-cost material, as it’s cheaper to synthesize than the MOF. A very relevant result is that other MOFs appear to be very good for CO2 capture when examined at lab scale using technical performance indicators, but fail when considered at industrial carbon capture conditions.”��

“This is very relevant in the search for the right materials for CO2 capture”, added Dr. AlHajaj. “Using the tool we have proposed to assess materials for carbon capture, including the right key performance indicators, will save time and economic efforts towards this goal.”

Zeolites are microporous materials commonly used as adsorbents and catalysts and are often considered “molecular sieves” as they can selectively sort molecules based primarily on a size exclusion process. However, they have limited capacity for CO2 capture and they are deactivated with water and other impurities. The best performing MOF would become a much more viable alternative if its production cost could be reduced. Hence the need for continued laboratory research on MOFs for use in carbon capture operations.

Jade Sterling
Science Writer
13 December 2021

The post On the Hunt for Carbon Capture Materials with Computer Modeling Technologies appeared first on Khalifa University.

Agreement Paves Way for Advancing Innovation in the Abu Dhabi Oil and Gas Sector ��

Khalifa University of Science and Technology and the Abu Dhabi National Oil Company (ADNOC) announced they have signed a research and development framework agreement for undertaking a joint research and development program that will advance innovation in the oil and gas sector in the areas of strategic importance to ADNOC.��

The agreement was signed by Dr. Arif Sultan Al Hammadi, Executive Vice-President, Khalifa University, and Abdulmunim Saif Al Kindy, Executive Director, People, Technology & Corporate Support Directorate, ADNOC, on the sidelines of the Abu Dhabi International Petroleum Exhibition and Conference (ADIPEC) 2021 that was held from 15-18 November at the Abu Dhabi National Exhibition Center (ADNEC).��

According to the agreement, a research and development board will be established with particular focus on upstream, downstream and digital solutions for the oil and gas industry and will have members from both partners. Khalifa University’s members are Dr. Steve Griffiths, Senior Vice-President, Research and Development; Dr. Saeed Alhassan, Senior Director, Petroleum Institute; and Dr. Ernesto Damiani, Senior Director, Robotics and Intelligent Systems Institute.��

Khalifa University’s Petroleum Institute is home to the Center of Catalysis and Separation (CeCaS) and the Research and Innovation Center on CO2 and H2 (RICH Center). The two research centers, along with other research undertaken at the Petroleum Institute and elsewhere at Khalifa University, contribute to technology innovations in areas such as hydrogen, carbon capture, catalysis and enhanced oil recovery. Khalifa University’s Robotics and Intelligent Systems Institute provides a broad spectrum of intelligent systems capabilities that can be tailored to the needs of the oil and gas sector.

Clarence Michael
English Editor Specialist
9 December 2021

The post Khalifa University and ADNOC Sign R&D Framework Agreement to Undertake Research and Development Program appeared first on Khalifa University.

With myriad materials to choose from, simulations help speed up the process of selecting the right materials for the job.��

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With most of the world still relying on fossil fuel-driven power plants for their energy, carbon dioxide emissions remain a global concern. Reducing greenhouse gas emissions, particularly carbon dioxide, is paramount in combating climate change.

One way to do this is to capture the carbon dioxide (CO₂) emissions directly from the smokestacks of the power plants before they enter the atmosphere.

Dr. Lourdes Vega, Director of the Khalifa University Research and Innovation Center on CO₂ and Hydrogen (RICH) and Professor of Chemical Engineering, is leading a collaborative research team that is analyzing different types of materials to determine their potential for post-combustion carbon dioxide capture and separation.

The team includes Dr. Daniel Bahamon, Research Scientist, and, Assistant Professor of Chemical Engineering, both from Khalifa University, along with Dr. Santiago Builes from EAFIT University, Colombia, and Wei Anlu from China University of Petroleum, a student who spent six months at the RICH Center at Khalifa University for performing part of this study. They published their work in January in the journal.

“Mitigation strategies such as carbon capture, utilization and storage (CCUS) play an import role in limiting the contribution of CO₂ emissions to global climate change. One key approach to this is capturing post-combustion CO₂ from flue gas at power stations and chemical manufacturing plants,” explained Dr. Vega.

Flue gas is the by-product gas that leaves a fossil fuel power station or plant via a chimney known as a flue. While its composition depends on what is being burned, it mostly comprises nitrogen, carbon dioxide, water vapor and a number of pollutants such as particulate matter, carbon monoxide, nitrogen oxides and sulfur oxides. The ‘smoke’ seen pouring from these flues is not smoke at all, but the water vapor in the gas forming a cloud as it meets cooler air.

Carbon dioxide is the second largest component of flue gas at around 4 to 25 percent, depending on the source. Although there are technologies available now to capture this carbon dioxide before it can wreak havoc on the atmosphere, they have several disadvantages.

Currently, aqueous amine solutions, which are solutions containing water and amines, organic compounds derived from ammonia and containing a nitrogen atom attached to hydrogen and carbon atoms, are used to capture CO₂ in large-scale applications. Amine solutions are excellent at trapping the CO₂, making them the most popular and developed carbon capture technology. However, the disadvantage to this technology is that in order to separate the trapped CO₂ from the amine solution, it has to be heated, requiring additional energy, and some of the amines are lost in this high energy process.

To overcome the shortcomings of amine solutions, solid sorbent materials are a viable alternative. Solid sorbents can selectively adsorb CO₂, however some solid sorbent materials perform better than others, and finding the most optimal carbon capturing material was the focus of Dr. Vega’s investigation.

A good adsorbent is a highly porous material with a large internal surface, full of holes to collect the CO₂. Metal-organic frameworks (MOF) materials possess enhanced stability, greater CO₂ cycling capacities and lower regeneration energies, making MOFs a material of choice for solid sorbent-based carbon capture.

However, MOFs alone are not enough to adsorb the CO₂ from flue gas at low pressures, especially since water vapor in the gas can compete with the carbon dioxide for adsorption. To counter this, attention has turned to amine-functionalized MOFs, where amines are grafted onto the open metal sites to increase CO₂ adsorption selectivity and capacity. These materials combine the benefits of both the MOFs and the amines, avoiding the disadvantages of the need for heating the solvent for removing the CO2 or the evaporation of the amines.

There are multiple types of amines, each of which has different characteristics relevant to CO₂ capture. Finding the optimal amine for each real-world application can be a time-consuming endeavor.

“Molecular simulations can allow the systematic and precise study of the various relevant variables of a system,” explained Dr. Vega. “We can isolate and quantify the effect of each functionalized MOF on the performance of the system, making simulation an excellent tool for the rational design of materials.”

The research team used molecular simulations to explore the relationship between the structure of different kinds of amine-grafted MOFs and their CO₂ adsorption performance.

A series of amine-grafted MOFs were screened, establishing the most promising materials for adsorbing low-concentration CO₂, while considering their regeneration performance, or how many cycles the MOFs could operate before degrading.

“Our work offers a molecular understanding of how functionalization takes place on MOFs and how it affects their final performance, providing guidance on the design of the best material/amine combination for optimal post-combustion CO₂ capture,” said Dr. Vega.�� Once the best material is found with this procedure, it will be synthesized and tested in a reactor at the conditions required for CO2 capture from different sources.

Dr. Vega’s team’s work is a significant contribution to the development of efficient and sustainable carbon capture utilization and storage solutions, as part of the RICH Center effort to find optimal materials to produce clean energy.��

Jade Sterling
Science Writer
15 April 2021

The post KU Team Develops Simulations to Find Materials for Capturing Carbon from Carbon Dioxide Emissions appeared first on Khalifa University.

As global energy demand from air conditioners continues to rise, finding a way to replace energy-intensive systems is paramount.

Read Arabic story .

As the mercury rises in the UAE, Dr. Lourdes Vega, Director of the Khalifa University Research and Innovation Center on CO2 and hydrogen (RICH), and KU Research Scientists Dr. Edder Garcia and Dr. Daniel Bahamon are turning their attention to finding efficient and environmentally-friendly forms of air conditioning systems.

“Due to global warming and a boost of wealth in tropical regions, the demand for refrigeration and air-conditioning is likely to increase in the coming years,” explained Dr. Vega. “This process already accounts for around 10 percent of the global electricity consumption, so finding green alternatives is of utmost importance.”

Global energy demand from air conditioners is expected to triple by 2050, and supplying power to these AC units comes with large costs and environmental implications.

Dr. Vega and her team are investigating a cleaner cooling process known as ‘absorption refrigeration,’ which could replace conventional energy-intensive vapor compression refrigeration, and could even be used as a way to store solar energy.

Conventional AC systems rely on vapor-compression cycles and a mechanical compressor. This is how it works: Refrigerant flows through a compressor, where it gets pressurized. Then the refrigerant flows through a condenser, where it condenses from vapor form to liquid form, giving off heat in the process. From the condenser, the refrigerant goes through an expansion valve and its pressure drops. Finally, the refrigerant travels to the evaporator, where it draws heat from the air around it (the air that needs to be cooled), which causes the refrigerant to vaporize. The vaporized refrigerant then goes back to the compressor to restart the cycle. In addition to the electricity consumption associated with air conditioning, in current vapor-compression cycles the refrigerant is usually a fluorinated gas (F-gas) with high global warming potential, making the phase out of such gases an urgent environmental need.

An adsorption-based refrigeration system is much simpler. It has two main components: a tank, where the liquid refrigerant is stored, and a bed filled with a solid material known as an ‘adsorbent.’ The refrigerant molecules ‘adsorb’, or attach, onto the surface of this material instead of dissolving into a liquid, creating a film on the surface where refrigerant vapor accumulates.

The adsorbent is a highly porous material with a large internal surface, full of holes that collect the refrigerant vapor. These systems transform energy into cooling power without any moving parts, making them low maintenance and more durable than conventional vapor-compression refrigeration systems.

Importantly, adsorption refrigeration can be powered by renewable energy sources, like the sun.

During energy production peaks, such as during the middle of the day for solar power supplies, heat is transferred to the adsorbent, causing the refrigerant to vaporize and desorb from the solid adsorbent. It detaches from the pores in the adsorbent and is condensed into a liquid for storage in the tank.

When it is time to cool down the air outside the unit, the liquid refrigerant is released to the evaporator, removing a heat from the surrounding area.

“When the refrigerant adsorbs onto the solid surface adsorbent, energy is released,” explained Dr. Vega. “Therefore, the adsorbent can be used as a thermal energy storage unit. Energy is stored during the removal of the refrigerant from the adsorbent material. The stored energy is recovered during the adsorption step and can be used as a low-temperature energy source. In this way, we can make a unit that both cools the air and stores energy.”

Developing such a unit however requires finding the perfect adsorbent-refrigerant pair. Currently, the most common refrigerants for domestic and automobile air conditioning and for vapor-compression cycles are hydrofluorocarbons, but these have tremendous global warming potential and are being phased out globally.

Using computational simulations, Dr. Vega and her team are trying to find the best adsorbent-refrigerant pair, and they are specifically looking for the ideal pairing with compounds known as metal-organic frameworks, or MOFs, combined with low global warming potential refrigerants including hydrofluoroolefins (HFO). They published their results in

“Several criteria can be used to select an adsorbent-refrigerant working pair,” said Dr. Vega. “The energy density that can be stored by adsorbent per unit of volume is an important indicator of performance. The difference in the adsorbed amount of refrigerant between adsorption and desorption—the working capacity—can also be considered. However, given the large number of potential materials that could be utilized, experimental evaluation is an expensive, time-consuming and tedious endeavor.”

Rather than individually test each pairing, the research team conducted simulations to guide selection of MOFs for thermal-storage applications. A total of 40 MOFs were studied using three refrigerants based on HFO, which has much lower global warming potential than the traditional hydrofluorocarbons.

The research team established a relationship between the adsorptive capacity and the properties of the materials, finding that MOFs with open metal sites interact strongly with the refrigerants, making them more suitable for thermal energy storage applications.

For cold thermal energy storage, MOFs with larger pore sizes showed a considerably higher energy density than the materials currently used commercially.

Jade Sterling
Science Writer
30 March 2021

The post Searching for Suitable Materials and Refrigerants for AC Units That Also Store Heat for Energy appeared first on Khalifa University.

Hydrogen is in high demand as an energy source but producing it can be difficult. A UAE-Japan research collaboration is looking to tackle these challenges and see the opportunities ahead.

Hydrogen could help tackle – critical energy challenges in the modern world, with its ability to provide a sustainable energy source to meet the demands for quality of life and economic growth, while avoiding emitting greenhouse gases into the atmosphere. Hydrogen use is expected to increase significantly in the near future in line with efforts to compensate the declining fossil fuel reserves and as the world turns to cleaner sources of energy.

Khalifa University’s Research and Innovation Center on CO2 and Hydrogen (RICH) is collaborating with the Institute of Energy Economics Japan (IEEJ) and Kyushu University on hydrogen projects in the UAE and Japan.

Collaboration between the UAE and Japan in the area of hydrogen began in 2017 with several bilateral meetings between academia, companies and government. In 2019, the first UAE-Japan Workshop on Hydrogen was held in Abu Dhabi with participants from UAE and Japanese industry and academia enjoying presentations, roundtable discussions, poster sessions and the exhibition of the Toyota Mirai Hydrogen FC Electric Vehicle. In 2020, a steering committee was created to define a roadmap and specific objectives and projects between IEEJ, Khalifa University, the Abu Dhabi National Oil Company (ADNOC), and the Abu Dhabi Department of Energy.

The low density of hydrogen made it a natural choice for one of its first practical uses—filling balloons and airships, but now, hydrogen can be used as a means of decarbonizing heavy industry; used as a zero-emission fuel for transportation, including trains, buses, trucks, and ships; provide a source of energy and heat for buildings; and store energy produced from renewable sources.

And there’s plenty of it. Hydrogen is found in the sun and most of the stars, and the planet Jupiter is composed mostly of hydrogen. On Earth, hydrogen is found in the greatest quantities as water. While it is present in the atmosphere, only tiny amounts of pure hydrogen persist since any hydrogen that does enter the atmosphere quickly escapes the Earth’s gravity into outer space.

Despite being the most abundant chemical substance in the universe, producing hydrogen is the tricky part. Most of the hydrogen produced today is from steam methane reforming, where natural gas is heated with steam to form syngas (a mixture of hydrogen and carbon monoxide), which is then separated to produce pure hydrogen. However, this process is energy intensive and comes with a large carbon footprint.

Considerable efforts have been made in recent years to find cleaner methods, mainly by water splitting using renewable sources of energy or by capturing the carbon dioxide produced by steam methane reforming.

Around 75 million tons of pure hydrogen are produced today, with 76 percent of that from natural gas and 23 percent from coal. Transitioning into low carbon energy with hydrogen is on the horizon. Hydrogen-derived synthetic fuels offer real potential for combining hydrogen with carbon dioxide to produce cleaner fuels for those traditionally ‘hard-to-reach’ sectors such as aviation and shipping, which have so far proved hard to convert to green energy.

Water splitting via electrolysis is expected to increase as surplus energy from renewables offers a low-cost way of providing the electricity needed. However, if all current dedicated hydrogen production were produced through water electrolysis, this would require more electricity than the annual generation of the European Union. It’s clear there are still several challenges to be solved.

There are various projects underway at RICH to meet these challenges. Solar-driven hydrogen production by water and hydrogen sulphide – a by-product of natural gas and oil processing – ��splitting is one such project.

Research shows that using 20 percent of the UAE’s land surface for solar plants producing green hydrogen for export would match the country’s current oil and gas revenue. Concurrently, using hydrogen to turn ammonia – another abundantly available resource – into a carbon-less fuel is also a focus for researchers in the center. Storing, processing, transporting and ultimately using these fuels requires an integrated infrastructure, which the researchers are also investigating via a systematic approach for optimal design and operation of a UAE hydrogen, carbon dioxide network.

With IEEJ, ADNOC, the Department of Energy, and Kyushu University, RICH is working to define a hydrogen smart town in Abu Dhabi in close relation to a more valuable oil and gas industry, while also developing a roadmap for research and development collaborations in low carbon hydrogen and hydrogen transportation.

As further opportunities in hydrogen production and use become apparent, the floor is open between the UAE and Japan to materialize them.

Jade Sterling
Science Writer
16 February 2021

The post Building Bridges: Opportunities Ahead in UAE-Japan Industry-Academia Collaboration on Hydrogen appeared first on Khalifa University.

For the seventh consecutive year, L’Oréal-UNESCO For Women in Science Middle East Regional Young Talents Program, in partnership with Khalifa University of Science and Technology, continues to recognize Arab female scientists from the GCC for their revolutionary researches in the fields of Life sciences, Physical sciences, Mathematics and Computer science.

The regional program is part of L’Oréal-UNESCO’s global initiative that has recognized over 3,400 phenomenal researchers since its inception 22 years ago.

This year, the program awarded six winners in the Post-doctorate Researchers and PhD Students categories where Dr. Maryam Tariq Khaleel Alhashmi (Khalifa University, UAE), Dr. Lama AlAbdi (KSA), and Dr. Isra Marei (Qatar), each received EUR 20,000 in the Post-doctorate Researchers category. Asrar Damdam (KSA), Dana Zaher (UAE), and Mina Al Ani (UAE) each received EUR 8,000 in the PhD Students category.

Dr. Maryam Tariq Khaleel Alhashmi, Assistant Professor of Chemical Engineering at KU and member of the Research and Innovation Center on CO2 and Hydrogen (RICH), has been recognized for her valuable contributions in the field of catalysis, specifically her research into the development of catalytic materials for sustainable production of chemicals.

Dr. Arif Sultan Al Hammadi, Executive Vice-President, Khalifa University��of Science and Technology,��added: “Spearheading towards Vision 2021 and Agenda 2030, the UAE has progressed immensely by creating an array of opportunities to support women empowerment, and Khalifa University continues to play a key role through its contribution in this area.

“With the recent pandemic worldwide, it is more important than ever that educational institutions especially universities, the scientific community and society at large encourage more women to bring their unique perspectives to the field. We are honoured to partner with L’Oréal-UNESCO For Women in Science Middle East Regional Young Talents Program for the second consecutive year and would like to congratulate the 2020 winners for their outstanding achievements and look forward to their future achievements.”

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To combat the threat of water scarcity in the Middle East, a team of researchers led by Dr. Lourdes Vega has investigated nanotechnology for water treatment and desalination purposes.

Read story in Arabic here:

The ten countries most threatened by water scarcity are concentrated in the Middle East, including the United Arab Emirates. To overcome the lack of sufficient fresh water, much of the water provided to the population is desalinated, with salt water treated to remove the salt and other impurities. This usually involves polymer-based membranes through which the water is run to catch the contaminants, but this isn’t the most efficient process and requires a lot of energy.��

A team of researchers led by Dr. Lourdes Vega, Professor of Chemical Engineering at Khalifa University and Director of the Research and Innovation Center on CO2 and H2 (RICH) and Dr. Daniel Bahamon, Research Scientist at the RICH Center, and Dr. Euon Seon Cho, Assistant Professor of Chemical and Biomolecular Engineering at KAIST, has investigated nanotechnology for water treatment purposes. They developed a graphene-based nanostructured membrane and analyzed its ability to allow water to permeate through and trap dissolved particles to efficiently clean the water.

“Due to rapid population growth and climate change, the demand for fresh and clean water has increased over time,” explained Prof. Vega. “However, fresh and clean water is easily contaminated by industrial development and human activities, so we need a method to keep our water resources clean. One such method is membrane filtration, which separates contaminants and salts from water in an energy efficient manner. Various types of membrane materials have been widely studied for this, but due to the poor mechanical and chemical stability of polymers, such membranes are unsuitable for large-scale cleaning processes. To find an alternative solution, we investigated graphene-based membranes, in particular, graphene oxide (GO) membranes.”

Graphene and its derivatives are emerging candidates for efficient water filtration membranes due to their unique nanochannel network, which allows water to permeate through but block unwanted solutes, as well as their robust chemical and physical stability. However, it is difficult to maintain their performance over time, which makes maintaining the fine nanochannels and designing the channels more carefully crucial to their longevity.

Over prolonged use, these nanochannels become blocked as the membrane swells. Research has shown that different positively charged ions (cations) can be used to manipulate the spacing between the molecules in the nanosheets, creating larger channels for filtration, but during pressure-assisted filtration (an indispensable procedure for water purification and desalination), it is difficult to keep the interaction between these cations and the GO layers stable.

“We needed to employ an additional molecule to tightly hold the interspersed cations between the GO sheets during the filtration process,” explained Prof. Vega. “We know that crown ether molecules can selectively bind to cations depending on their cavity size and composition so we used a controlled amount of these in our graphene-oxide composite membranes.”

Crown ether molecules are chemical compounds that form a ring containing several ether groups. The research team prepared the GO membrane with potassium ions and crown ethers to create a nanochannel complex that was partially narrowed compared to the pristine GO membrane. This sub-nanochannel has an important role in blocking the permeation of ions during pressure-assisted filtration.

The team found that the complex of crown ethers and potassium ions plays a key role in tailoring the nanochannels, implying that the approach can be further tailored by varying the concentration and type of inserted crown ether molecules and cations. Additionally, the mixed salt solution used in testing was beneficial to maintaining the crown ether complex structure, which is important for real seawater applications.

“Water is the ultimate systems challenge,” said Prof. Vega. “It is a unique resource that underpins all drivers of growth—from agricultural production to energy generation, industry, and manufacturing. It also connects these sectors into a broader economic system that must balance social development and environmental interests.

“The joint effort between the team at Khalifa University and KAIST led to the fabrication and testing of the membranes at the lab scale as well as the understanding of their performance through molecular simulations. Our next steps will involve research into its stability and the potential for scaling-up production as well as other membranes based on graphene oxide for water treatment.”

Jade Sterling
Science Writer
2 November 2020

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