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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…

Presentation

Synthesis of Ammonia By RF Non-Thermal Plasma over Ni-MOF-74

Maria Carreon

Herein, we demonstrate a synergistic approach consisting on radiofrequency plasma to synthesize ammonia in the presence of Ni-MOF-74 as catalyst. The Ni-MOF displayed higher ammonia yields as com-pared to the pure Ni metal. Specifically, ammonia yields as high as 0.23 g-NH3 (kWh-g-catalyst)-1 and energy cost of 265 MJ mol-1 over Ni-MOF were observed. The enhanced catalytic activity of the Ni-MOF in the presence of plasma was attributed to the presence of pores that improved mass transfer of guest and product molecules during reaction, the presence of open Ni metal sites, and lower surface hydrogen re-combination. Furthermore, the ammonia energy yield…

Presentation

Demonstration of CO2-Free Ammonia Synthesis Using Renewable Energy-Generated Hydrogen

Mototaka Kai Yasushi Fujimura Takayoshi Fujimoto Hideyuki Takagi Yuichi Manaka Tetsuya Nanba

In Japan, the government funding project SIP, Strategic Innovation Promotion Program, supports the research, development and demonstration of “Energy Carriers”. The concept of the “Energy Carriers” value chain is to produce hydrogen energy carriers overseas from fossil resources using CCS or renewable energy, and transport it to Japan for utilization as clean energy. The purpose of the program is to help realize a low-carbon society in Japan by using hydrogen. Among energy carriers, ammonia is the one of the most promising carriers, because of the ease of transportation as a liquid, higher hydrogen density, and proven technologies for commercial and…

Presentation

Analysis of influence of operating pressure on dynamic behavior of ammonia production over ruthenium catalyst under high pressure condition

Hideyuki Matsumoto Javaid Rahat Yuichi Manaka Mika Ishii Tetsuya Nanba

Process technologies on energy conversion of renewable electricity into hydrogen energy carrier are significant to deploy long-term storage and long-distance transport of much more renewable inside and outside Japan. Ammonia is a potential hydrogen carrier that contains 17.6 wt% of hydrogen. Moreover, as an energy carrier, ammonia is thought to be a clean fuel as only water and nitrogen are produced on direct combustion. Many researchers and engineers consider that ammonia plants using hydrogen produced by solar electricity or wind electricity will be much smaller than those currently used [1]. There is an issue of low pressure condition for feed…

Presentation

Highly-Selective Electrochemical Reduction of Dinitrogen to Ammonia at Ambient Temperature and Pressure

Qiang Zhang Xiaoyang Cui Cheng Tang

Catalytic conversion of dinitrogen (N2) into ammonia under ambient conditions represents one of the Holy Grails in catalysis and surface science. As a potential alternative to the Haber-Bosch process, electrochemical reduction of N2 to NH3 is attractive owing to its renewability and flexibility, as well as sustainability for producing and storing value-added chemicals from the abundant feedstock of water and nitrogen on earth. However, owing to the kinetically complex and energetically challenging N2 reduction reaction (NRR) process, NRR electrocatalysts with high catalytic activity and high selectivity are rare. In this contribution, as a proof-of-concept, we demonstrate that both the NH3…

Presentation

A Low Pressure Membrane Based Renewable Ammonia Synthesis

Sarbjit Giddey

Ammonia is currently mostly produced by the highly energy and carbon-intensive Haber–Bosch process, which requires temperatures of 450–500 °C and pressures of up to 200 bar. The feedstock for this process is hydrogen from natural gas (NG), coal or oil, and nitrogen produced from air by cryogenic route or pressure swing adsorption (PSA). The share of NG, coal and fuel oil feedstock for the global production of ammonia is 72%, 22% and 4% respectively, contributing to approximately 420 million tons of CO2 emissions per annum, representing over 1% of global energy related emissions. The energy consumed for ammonia synthesis by…