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This isn't using ammonia to transport hydrogen; the nitrogen is what's reacting with the iron. And yes, ease of transportation and reactivity is a big motivato

This isn't using ammonia to transport hydrogen; the nitrogen is what's reacting with the iron. And yes, ease of transportation and reactivity is a big motivator. From the abstract: "Ammonia is an annually 180 million ton traded chemical energy carrier, with established transcontinental logistics and low liquefaction costs. It can be synthesized with green hydrogen and release hydrogen again through the reduction reaction." Also: "The authors show that ammonia-based reduction of iron oxide proceeds through an autocatalytic reaction, is kinetically as effective as hydrogen-based direct reduction, yields the same metallization, and can be industrially realized with existing technologies."

thereisnospork 4y ago
>the nitrogen is what's reacting with the iron. Only in a supplementary manner to form a nitride coating as rust proofing - the primary reducing agent is hydrogen, forming water. relevant snippet: >>The nitride formation is another key advantage of ADR, as nitriding improves the aqueous corrosion resistance of iron.[29] The nitride passivated the otherwise highly active reduced iron, offering a safety-critical benefit for handling and logistics. Otherwise, for the downstream processing of the reduced material, the porous sponge iron is prone to re-oxidation and strong exothermic reactions with oxygen or moisture due to its high surface-to-volume ratio (typically above 40 vol% porosity[4]). Thus, the sponge iron produced by HyDR must be compacted into hot briquetted iron to reduce the porosity for shipping and handling, which is not necessary with ADR.