Mechanocatalytic Room‐Temperature Synthesis of Ammonia from Its Elements Down to Atmospheric Pressure. (8th November 2021)

• Record Type: Journal Article
• Authors: Reichle, Steffen; Felderhoff, Michael; Schüth, Ferdi
• Is Part Of: Angewandte Chemie. Volume 133:Number 50(2021)
• Page Start: 26589
• Page End: 26593
• Publication Date: 2021-11-08
• Subjects: ammonia synthesis -- catalysis -- gas-phase reactions -- mechanochemistry -- room-temperature; Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.202112095
• Languages: English
• ISSNs: 0044-8249

Abstract

Abstract: Ammonia synthesis via the high‐temperature and high‐pressure Haber‐Bosch process is one of the most important chemical processes in the world. In spite of numerous attempts over the last 100 years, continuous Haber‐Bosch type ammonia synthesis at room‐temperature had not been possible, yet. We report the development of a mechanocatalytic system operating continuously at room‐temperature and at pressures down to 1 bar. With optimized experimental conditions, a cesium‐promoted iron catalyst was shown to produce ammonia at concentrations of more than 0.2 vol. % for over 50 hours. Abstract : Mechanocatalytic ammonia synthesis over Fe catalysts promoted by alkali metals, especially Rb or Cs, is possible under ball milling. The reaction proceeds at appreciable rates at room‐temperature and down to atmospheric pressure in a continuously operating system under gas flow.