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Presentation

Yittria-Stabilized Zirconia (YSZ) Supports for Low Temperature Ammonia Synthesis

Zhenyu Zhang Sarah Livingston Lucy Fitzgerald Thomas F. Fuerst Simona Liguori J. Douglas Way Colin A. Wolden

NH3 is important as the raw material for fertilizer production and high hydrogen density (17.7 wt. %) energy carrier. Conventionally, NH3 is synthesized through the well-known Haber-Bosch process at 400-500°C and P~150 bar. Both critical reaction conditions and massive production (145 mt NH3 in 2014 globally) make it one of the most energy extensive process, consuming 1-2% of the world’s total energy expense. Here we introduce YSZ as a more active Ru catalyst support than traditionally used supports such as Al2O3. The addition of Cs promoter increased rates an order of magnitude higher by reducing the apparent activation energy from…

Presentation

Electrochemical Reduction of Dinitrogen to Ammonia Using Different Morphologies of Copper As Electro Catalysts

Nishithan C. Kani Meenesh R. Singh

Ammonia is an effective hydrogen storage medium due to ease of transport as liquid, high storage capacity (17.65%) and it can easily be converted to hydrogen by electro-chemical oxidation. Haber-Bosch process is used for the synthesis of ammonia which is energy intensive as it requires high temperature and pressure. It also causes intense carbon emissions as the hydrogen is produced by steam reforming. Alternatively, ammonia can be synthesized electrochemically at ambient conditions from nitrogen and water by employing renewable energy in the presence of an electro catalyst. The major challenge in electrochemical synthesis of ammonia is low Faradaic efficiency. This…

Presentation

In Situ Growth of Nitrogen-Doped Carbon Coated γ-Fe; O; Nanoparticles on Carbon Fabric for Electrochemical N; Fixation

Yan Li Yang Hou

Nitrogen fixation to ammonia (NH3) has attracted intensive attention because NH3 is the critical inorganic fertilizers and energy carrier. Haber-Bosch process, the industrial procedure for NH3 production, is confined to the extreme condition requirements. Hence, it is highly desirable to develop a renewable and environment-friendly route for nitrogen fixation to replace the conventional technology. Electrochemical nitrogen reduction reaction (NRR) is one of the most promising techniques since the electrical energy could be produced by synergy with the fast-growing renewable energy. However, electrochemical NRR approach faces huge challenge in breaking extremely high N≡N bond energy (940.95 kJ mol–1) in dinitrogen molecules.…

Presentation

Electrochemical Promotion of Ammonia Synthesis with Proton-Conducting Ceramic Fuel Cells -Function of Electrode Interface for Ammonia Formation Reaction-

Junichiro Otomo Chien-I Li Kazunori Yamamoto Hiroki Matsuo

The advance of efficient and economical energy carrier technology is an important challenge in terms of storage and transport of hydrogen fuels produced from renewable energy. Ammonia is a promising candidate of energy carrier because of high energy density and easy liquefaction as well as a carbon-free fuel.1 Electrochemical synthesis has a potential for an efficient ammonia production in comparison with the industrial Haber–Bosch process. In our previous study, we observed the improvement of electrochemical synthesis of ammonia using iron-based electrode catalyst such as K-Al-Fe-BaCe0.9Y0.1O3 (BCY).2 In the study, basically, H2 decomposition occurs to form protons in the anode side,…

Presentation

Activation By High Temperature Reduction of Ru Catalyst Supported on Rare Earth Oxide for Ammonia Synthesis

Yuta Ogura Katsutoshi Nagaoka Katsutoshi Sato

Ammonia is an important chemical feedstock, and more than 80% of the synthesized ammonia is used to produce fertilizer. Ammonia is also being considered as an energy carrier and hydrogen source (1) because it has a high energy density (12.8 GJ m-3) and a high hydrogen content (17.6 wt%), (2) because infrastructure for ammonia storage and transportation is already established, and (3) because carbon dioxide is not emitted when ammonia is decomposed to produce hydrogen. If ammonia could be efficiently produced from a renewable energy source, such as solar or wind energy, problems related to the global energy crisis could…

Presentation

Ammonia Decomposition and Separation Using Catalytic Membrane Reactors

Sai P. Katikaneni Stephen N. Paglieri Aadesh X. Harale Aqil Jamal Koichi Eguchi Hiroki Muroyama Toshiaki Matsui

Hydrogen is the primary fuel source for fuel cells. However, the low volume density and difficulty in storing and transporting hydrogen are major obstacles for its practical utilization. Among various hydrogen carries, ammonia is one of the most promising candidates because of its high hydrogen density and boiling point and ease in liquefaction and transportation. The reaction temperature of ammonia cracking into nitrogen and hydrogen is about 500˚C or higher. The hydrogen can be effectively separated by the membrane based on Pd alloy about 500˚C. Currently, the extraction of hydrogen from ammonia is carried out by two step process involving…

Presentation

High Flow Ammonia Cracking between 400-600°C

Adam Welch Jonathan Kintner Christopher Cadigan Ryan O'Hayre Joseph Beach

Traditional ammonia cracking is achieved at 850-950 °C in the presence of a nickel catalyst. The reaction is highly endothermic, and maintaining these high temperatures at high flow rates of ammonia gas can be difficult. Here, we present work using our advanced ammonia synthesis catalyst in an ammonia cracking setup. We use a metallic monolith catalyst support to minimize pressure drop at high flow rates. Full NH3 cracking occurs at 600 °C, with the onset of cracking at 400 °C. An output flame can be achieved with a fully tunable ratio of hydrogen to ammonia, depending on the temperature setpoint…

Presentation

Material Discovery and Investigation of Novel Y Containing Ru Catalysts for Low Temperature Ammonia Decomposition

Katie McCullough Travis Williams Jochen Lauterbach

Liquid ammonia can be used as an alternative hydrogen carrier and can be decomposed over catalysts to create a high purity hydrogen stream for fuel cell applications. Ammonia decomposition is typically catalyzed using supported ruthenium catalysts. Current ruthenium catalysts are expensive and often require reaction temperatures of 650 °C to attain complete conversion [1]. For the hydrogen produced from ammonia decomposition to be efficiently used in proton exchange membrane fuel cells, operating temperatures need to be considerably lowered and effluent concentrations of ammonia need to be minimized to avoid poisoning of the membrane [2]. Therefore, it is of interest to…

Presentation

Carbon-Free H2 Production from NH3 Triggered at Ambient Temperature with Oxide Supported Ru Catalysts

Katsutoshi Nagaoka Katsutoshi Sato Yuta Ogura

Hydrogen produced from renewable energy has received a lot of attentions as a clean energy and development of a hydrogen storage and transportation system using hydrogen carrier has been greatly demanded. Among different kinds of hydrogen carrier, NH3 is regarded as one of the promising candidates, due to high energy density, high hydrogen capacity, and ease of liquification at room temperature. Furthermore, a carbon-free hydrogen storage and transportation system could be realized by using NH3 as hydrogen carrier. In this system, hydrogen produced from NH3 is used in engines, fuel cells, and turbines. However, use of NH3 as a hydrogen…

Presentation

Microwave Catalytic Synthesis of Ammonia for Energy Storage and Transformation

Xinwei Bai Dushyant Shekhawat Christina Wildfire Albert E. Stiegman Robert A. Dagle Jianli Hu

This paper presents an innovative approach of producing energy-dense, carbon-neutral liquid ammonia as a means of energy carrier. The approach synergistically integrates microwave reaction chemistry with novel heterogeneous catalysis that decouples N2 activation from high temperature and high pressure reaction, altering reaction pathways and lowering activation energy. Results have shown that ammonia synthesis can be carried out at 280 ℃ and ambient pressure to achieve ~1 mmol NH3/g cat. /hour over supported Ru catalyst systems. Adding promoters of K, Ce and Ba has significantly improved the ammonia production rate over Ru-based catalysts that could be attributing to enhanced electromagnetic sensitivity…