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Progress in the Electrochemical Synthesis of Ammonia
Presentation

Progress in the Electrochemical Synthesis of Ammonia

V KyriakouI GaragounisE VasileiouA VourrosM 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 MuroyamaJun YangKaname OkuraTakeou OkanishiToshiaki MatsuiMotohiro SaitoHiroshi IwaiHideo YoshidaKoichi 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.…

Student Laboratory Module: Kinetics of Ammonia Cracking
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…

Making and Treating NOx formed in NH3 Engines
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.…