RETRACTED: Ammonia synthesis. Ammonia synthesis by N₂ and steam electrolysis in molten hydroxide suspensions of nanoscale Fe₂O₃

Science. 2014 Aug 8;345(6197):637-40. doi: 10.1126/science.1254234.

Abstract

The Haber-Bosch process to produce ammonia for fertilizer currently relies on carbon-intensive steam reforming of methane as a hydrogen source. We present an electrochemical pathway in which ammonia is produced by electrolysis of air and steam in a molten hydroxide suspension of nano-Fe2O3. At 200°C in an electrolyte with a molar ratio of 0.5 NaOH/0.5 KOH, ammonia is produced at 1.2 volts (V) under 2 milliamperes per centimeter squared (mA cm(-2)) of applied current at coulombic efficiency of 35% (35% of the applied current results in the six-electron conversion of N2 and water to ammonia, and excess H2 is cogenerated with the ammonia). At 250°C and 25 bar of steam pressure, the electrolysis voltage necessary for 2 mA cm(-2) current density decreased to 1.0 V.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.
  • Retracted Publication

MeSH terms

  • Ammonia / chemical synthesis*
  • Electrolysis / methods*
  • Ferric Compounds / chemistry*
  • Fertilizers*
  • Hydroxides / chemistry*
  • Nitrogen / chemistry*
  • Steam*

Substances

  • Ferric Compounds
  • Fertilizers
  • Hydroxides
  • Steam
  • ferric oxide
  • Ammonia
  • hydroxide ion
  • Nitrogen