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Ammonia is a vital agricultural input and could be a carbon-free energy vector. An experimental proof-of-concept of a novel thermochemical cycle to produce NH3 and syngas (CO-H2) at atmospheric pressure from N2, steam, and shale gas (CH4) is demonstrated here: Mn was reacted with N2 forming Mn-nitride, corrosion of Mn-nitride with steam at 500 °C formed MnO and NH3, and finally MnO was reduced at 1150 °C in a 4 vol % CH4–96 vol % N2 stream to Mn-nitride, closing the cycle. Optimum nitridation at 800 °C and 120 min produced a Mn6N2.58-rich Mn-nitride mixture containing 8.7 ± 0.9 wt % nitrogen. NH3 yield was limited to 0.04 after 120 min during nitride corrosion, but addition of a NaOH promotor improved NH3 yield to 0.54. Mn6N2.58 yield was 0.381 ± 0.083 after MnO reduction for 30 min with CO and H2, but no CO2 detected in the product.

A zinc/alkaline/manganese dioxide packed-bed electrode flow battery was used to evaluate using granular materials with ionic activity as separating materials between electrodes, increasing the separation distance between electrodes, while using separating materials, and reversing the electrolyte flow direction through the flow battery. Results indicate that materials with more ionic activity (ion exchange resins) perform better than materials with limited ionic activity (stainless steel). Among the more ionically active materials, the basic material out-performed the acidic material with an anode-to-cathode flow regime at low current draw. The best performance was obtained using ALL-CRAFT 4K-activated carbon as separation material. The use of an ionically active separation material reduced the difference in cell performance between 2.22 and 5.40 cm of separation by 56%. Although expected to be an important parameter for packed-bed electrode flow battery, the electrolyte flow direction did not produce a discernable difference in performance using the low current draw of these studies.

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We describe the design, construction, operation, and performance of a simple and versatile semi-batch reactor that is especially useful for measurement of gas/solid reaction rates at pressures in the range of 1 mTorr to 1500 Torr. The reactor operates by repeatedly imposing small AC modulations of reactant gas pressure on top of a much larger DC pressure background. Based on the rate of pressure relaxation following each AC pulse, the reaction rate is determined. Our design is characterized by modular construction from off-the-shelf, ultra-high-vacuum-compatible components, which facilitate easy retrofitting and adaptation to a range of experimental conditions. Automated experiment control and data acquisition is accomplished via a custom National Instruments© LabView virtual instrument. Data analysis is automated using a custom series of Mathworks© Matlab scripts. We demonstrate reactor performance through measurements of hydrogenation kinetics for a composite H2 getter material consisting of 1,4-bis(phenylethynyl)benzene mixed with a palladium/carbon catalyst.