This paper introduces the existing literature on the safety of using ammonia as a fuel, which provides comparative data for a range of traditional and alternative fuels and energy carriers. The studies reviewed conclude that risk levels associated with using ammonia as a fuel are “similar to those of gasoline,” or “similar, if not lower than for the other fuels,” also including hydrogen, methanol, LPG, and CNG. Ammonia as a fuel can meet all “acceptable” risk levels in even the most stringent regulatory jurisdictions. Addressing popular misconceptions and fears by providing robust sources for quantitative data on the dangers of…

The project proposes a comprehensive investigation on the analysis, assessment and optimization of ammonia synthesis processes under renewable energy portfolio, including low-cost hydro, wind, solar, geothermal, ocean, biomass, etc. Furthermore, ammonia production via hydrocarbon decomposition, which will be investigated in the study, is a promising option to utilize fossil fuels in a cleaner and environmentally benign way. Case studies for various locations and applications in communities, cities and provinces to develop and implement clean solutions are performed. The objectives of this project include energy and exergy analyses, environmental impact assessments, thermo-economic analyses and evaluations, optimization studies, experimental investigation, scalability and…

Ammonia is considered as a promising hydrogen-carrier with good storability and transportability, which, then, can be used as a carbon-free fuel as needed. However, once the ammonia is produced from the regenerative sources, it is essential to develop the energy conversion device of the chemical energy stored in ammonia into some other useful forms, e.g. electricity. Among various candidates, we focus on an internal combustion engine as energy conversion device which can be applied on automobile, power plant and etc. and can use ammonia as fuel only by simple modification. There have been many studies on the use of ammonia…

The fluctuating nature of renewable energy sources is becoming a limiting factor in their widespread utilization. Energy storage solutions must be developed to overcome this issue. Chemical fuels are considered to be a promising solution to this problem. We are studying the implementation of nitrogen-based fuels for this purpose. An aqueous solution of ammonium nitrate and ammonium hydroxide (AAN) is suggested as a carbon-free nitrogen-based synthetic monofuel. This solution may serve as a renewable nitrogen-based synthetic hydrogen carrier since it is safe to store, transport and utilize. Since ammonium hydroxide (AH) and ammonium nitrate (AN) act as reducer and net…

The most effective ammonia cracking catalysts are currently based on rare metals such as ruthenium and cobalt. While iron can efficiently crack ammonia at 600 °C, it is desirable to develop similarly inexpensive catalysts that are effective at lower temperatures between 350 °C and 500 °C. In this presentation, a new family of imide-based catalysts are described that crack ammonia around 400 °C to 550 °C. These materials do not behave as conventional surface-based catalysts and offer an affordable route for on-board cracking of ammonia for hydrogen fuel-cell cars. The operational parameters of a small 50W lab-based demonstrator will be…

Starfire Energy is developing a fast-ramping reactor for making CO2-free NH3 for fuel, energy storage, and agricultural applications. A fast-ramping reactor is desired to follow (a) variable electricity generation from CO2-free sources such wind and solar power plants or (b) variable availability from CO2-free baseload electricity generation such as nuclear or hydroelectric power plants. The reactor builds upon the Haber-Bosch process by (a) introducing a higher activity supported Ru catalyst (over 4.5 mmol g-1 h-1 at 1 atm and over 45 mmol g-1 h-1 at 10 atm) and (b) further enhancing the catalysis by applying an electric potential or electric…

Ammonia-based fertilizers have enabled increases in food production to sustain the world’s population. Currently the major source of ammonia is the Haber-Bosch process, which requires high temperature and pressure and has low conversion efficiency, such that very large plants are required for economical production. Ammonia is therefore one of the most energy and carbon intensive chemical processes worldwide, largely due to the steam methane reforming step to produce the required hydrogen. Because of the very large plant scale and resulting centralization of production, ammonia may also be transported long distances to point of use, adding additional energy and emissions. Distributed,…

More than 180 million tons of NH3 are produced annual via the Haber-Bosch process which converts N2 and H2 at high temperatures (400 – 500°C) and pressures (150 – 300 bars). Ammonia synthesis also accounts for 1-2% of global energy consumption.1 The development of higher activity catalysts that can operate under less severe conditions would enhance the economics associated with and sustainability of NH3 synthesis. Research described in this paper investigates the performance of transition metal carbide and nitride supported metals for NH3 synthesis. Previously, Mo2C and Mo2N have been reported to be more active than Ru-based catalysts, but slightly…

Having a hydrogen content of 17.6 wt% NH3 is an attractive hydrogen carrier. The key issue for NH3 synthesis and decomposition is the development of non-noble metal based, highly active and stable catalysts that can be operated under mild condition. With the understanding on the interaction of LiH and Li2NH with 3d metals or their nitrides, novel catalyst systems, i. e., LiH-3d transition metals for NH3 synthesis and Li2NH-3d transition metal for NH3 decomposition, that have activities surpassing the highly active Ru-based catalysts were developed. The unique chemistry among TM, Li, N and H creates a two-reactive center mediated pathway…

Commercial ammonia synthesis relies on the Haber–Bosch process that has remained largely unchanged for a hundred years. The equilibrium constant of this exothermic reaction quickly becomes unfavorable above 200 °C, but the catalyst requires temperatures above 400 °C to have sufficient activity. To overcome these conflicting requirements the process is conducted at extremely high pressure (100 – 200 atm) using multiple passes with inter-stage cooling to achieve sufficient conversion. A cost analysis reveals the compressors needed to reach the required pressures consist of 50% the capital cost for Haber-Bosch. Therefore, a longstanding scientific challenge has been to achieve NH3 synthesis…

Synthetic ammonia production has played a huge role in sustaining population growth by providing the nitrogen in fertilizers that are widely used in modern agriculture. Even long after it was first commercially developed by Fritz Haber and Carl Bosch in the 1930s, the Haber-Bosch process remains the basis for industrial ammonia production today. Through reducing energy requirements by half in the last 50 years, centralized industrial plants have kept their technical and economic advantage over other modes of operation. However, the centralized production also comes with high transportation costs, since plant capacities usually exceed local ammonia consumption [1]. This and…

Haldor Topsøe’s leading role as supplier of ammonia synthesis catalysts and technology is well known. The company has, however, also been active for decades in developing Solid Oxide Cell based stacks and systems. The presentation will describe a novel, highly integrated process for ammonia synthesis based on Solid Oxide Electrolysis. The energy efficiency is very high due to ability of the SOEC to use steam generated from the synthesis reaction heat in the ammonia synthesis loop and the favorable thermodynamics of high temperature electrolysis. Experimental results from hydrogen generation from steam using SOEC and power production from ammonia using Solid…