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Article

International R&D on sustainable ammonia synthesis technologies

Trevor Brown February 03, 2017

Over the last few weeks, I've written extensively about sustainable ammonia synthesis projects funded by the US Department of Energy (DOE). While these projects are important, the US has no monopoly on technology development. Indeed, given the current uncertainty regarding energy policy under the Trump administration, the US may be at risk of stepping away from its assumed role as an industry leader in this area. This article introduces seven international projects, representing research coming out of eight countries spread across four continents. These projects span the breadth of next-generation ammonia synthesis research, from nanotechnology and electrocatalysis to plasmas and ionic liquids.

Presentation

Research and Development of Ammonia-fueled SOFC Systems

Koichi Eguchi Atthapon Srifa Takeou Okanishi Hiroki Muroyama Toshiaki Matsui Masashi Kishimoto Motohiro Saito Hiroshi Iwai Hideo Yoshida Masaki Saito Takeshi Koide Hiroyuki Iwai Shinsuke Suzuki Yosuke Takahashi Toshitaka Horiuchi Hayahide Yamasaki Shohei Matsumoto Shuji Yumoto Hidehito Kubo Jun Kawahara Akihiro Okabe Yuki Kikkawa Takenori Isomura

Ammonia is a promising hydrogen carrier because of its high hydrogen density, low production cost, and ease in liquefaction and transport. Ammonia decomposes into nitrogen and hydrogen through a mildly endothermic process. The ammonia decomposition temperature is close to the operating conditions of solid oxide fuel cells (SOFCs). Therefore, the integration of these two devices is beneficial in terms of efficient heat and energy managements and will lead to the development of simplified generation systems. We have investigated three types of ammonia-fueled SOFC systems. In one system, ammonia is directly supplied to the anode chamber. Ammonia decomposes into nitrogen and…

Presentation

Cracking ammonia

Bill David Josh Makepeace Hazel Hunter Thomas Wood

In this talk, I will discuss our latest research in developing novel ammonia cracking catalysts. While ammonia can be used directly as a fuel in high temperature fuel cells, internal combustion engines and gas turbine, the ability to crack ammonia affordably and effectively increases the range of possibilities for utilising ammonia as an energy vector. For example, the production of an ammonia-free hydrogen/nitrogen gas mixture permits the consideration of ammonia as an on-board hydrogen storage option for transportation. Furthermore, the ability to partly crack ammonia provides an increased flexibility for internal combustion engines. I will outline developments in our search…

Presentation

Applications of hydrogen permeable membranes in ammonia synthesis and decomposition

Sean Lundin Thomas F. Fuerst Jason Ganley Colin A. Wolden J. Douglas Way

It is well known that ammonia is being considered as a method of storing hydrogen. Although some fuel cells are being developed that can use ammonia directly as a fuel source, many fuel cell technologies still require an outside cracker to revert ammonia back into hydrogen for efficient use. In this regard, hydrogen permeable membranes, such as Pd and its alloys, have been targeted as potential membrane reactors in which the ammonia is cracked while the hydrogen is simultaneously separated. Pd and its alloys are expensive, but offer potentially perfect hydrogen purity that is highly preferable for certain fuel cells…

Presentation

Progress in the Electrochemical Synthesis of Ammonia

V Kyriakou I Garagounis E Vasileiou A Vourros M Stoukides

Ammonia is one of the most important and widely produced chemicals worldwide with a key role in the growth of human population. Nowadays, the main route for ammonia synthesis is the Haber-Bosch process, developed one century ago. In this process, Fe-based catalysts are usually employed at temperatures between 400 and 500°C and pressures between 130 and 170 bar. As opposed to the industrial process, in nature, plants and bacteria have been producing ammonia for millions of years at mild conditions. Atmospheric nitrogen is reduced by solvated protons on the FeMo cofactor of the metalloenzyme nitrogenase. The natural method of nitrogen…

Presentation

Research and development of NH3-fueled solid-state fuel cell systems

Hiroki Muroyama Jun Yang Kaname Okura Takeou Okanishi Toshiaki Matsui Motohiro Saito Hiroshi Iwai Hideo Yoshida Koichi Eguchi

Ammonia is a prospective carbon-free fuel source for fuel cell systems due to low production cost, ease in liquefaction at ambient temperatures, and high energy density. Furthermore, hydrogen and nitrogen originating from ammonia fuel are expected to have little negative effect on fuel cell performance, while hydrocarbon fuels draws some severe problems at electrodes, such as CO poisoning or carbon deposition in low- and high-temperature fuel cells, respectively. Several technologies can be considered for the ammonia utilization in fuel cell systems. For the utilization of ammonia fuel, we aim to develop a system combined with ammonia decomposition reactor and solid-state…

Presentation

A novel approach to ammonia decomposition

Bill David

This talk discusses a new type of process for the cracking of ammonia (NH3) that is an alternative to the use of rare or transition metal catalysts. Effecting the decomposition of NH3 using the concurrent stoichiometric decomposition and regeneration of sodium amide (NaNH2) via sodium metal (Na), this represents a significant departure in reaction mechanism compared with traditional surface catalysts. In variable-temperature NH3 decomposition experiments, using a simple flow reactor, the Na/NaNH2 system shows superior performance to supported nickel and ruthenium catalysts, reaching 99.2% decomposition efficiency with 0.5 g of NaNH2 in a 60 sccm NH3 flow at 530 °C.…

Presentation

Student Laboratory Module: Kinetics of Ammonia Cracking

Jason Ganley

The Chemical and Biological Engineering (CBE) Department at the Colorado School of Mines is dedicated to the continual improvement of the laboratory resources made available to those undergraduates enrolled in courses which have major or minor laboratory components. One such course is Kinetics and Reaction Engineering (CBEN 418), offered to undergraduate seniors in the CBE department. Historically, this course has been delivered primarily as a series of traditional classroom lectures with an experimental module (usually one week at the end of the semester) with about 2 hours of participation time per student outside of normal class hours. Previous experimental designs…

Presentation

Making and Treating NOx formed in NH3 Engines

Patrick Desrochers

Ammonia has real promise as a green renewable fuel; however its use is not without some of the drawbacks endemic to high temperature combustion processes. Chief among them is the potential for NOx formation in nitrogen-rich oxidizing environments. Nitric and nitrous oxides are prime culprits that plague both entrenched hydrocarbon internal combustion technology but also emerging technologies like ammonia-as-a-fuel. Nitric oxide is implicated in photochemical ground-level ozone production in urban areas. Nitrous oxide is its own double-edged environmental sword, being both a potent tropospheric green-house gas as well as a principle agent in renewed stratospheric ozone-depletion (Science 2009, v326, p.…

Presentation

Transition-Metal Catalyzed Reduction of Nitrogen to Ammonia

Andreja Bakac Aaron Sadow Oleg Pestovsky Barun Jana

Transition-Metal Catalyzed Reduction of Nitrogen to Ammonia Andreja Bakac, Aaron Sadow, Oleg Pestovsky, and Barun Jana, Iowa State University