Re:Reducing Iron Oxide with Ammonia: A Sustainable Path to G...
by thereisnospork on Sunday April 02, 2023 @04:17PM
(#35414703)
>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.
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.