Hydroxylamine: an overseen intermediate that brings into question nitrogen selectivity in metal-catalyzed nitrate and
Janek Betting1, Leon Lefferts1, Jimmy Faria Albanese1
1Catalytic Processes and Materials Group, Department of Chemical Engineering, Faculty of Science and Technology, MESA+ Institute for Nanotechnology, University of Twente, Enschede 7500 AE, The Netherlands. l.lefferts@utwente.nl.
Abstract:
In decades of nitrate and nitrite hydrogenation research, nitrite, ammonia, and nitrogen gas were assumed to be the only relevant products. However, we have discovered hydroxylamine on several metal catalysts under various reaction conditions using a simple derivatization strategy based on the oximation of benzaldehyde with hydroxylamine. This previously overlooked intermediate challenges pervasive assumptions of nitrogen gas selectivity and compels a reexamination of the reaction mechanism. Additionally, the hydroxylamine presence represents a major setback for the application of catalytic nitrate and nitrite reduction in drinking water purification.
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