A process for decentralized ammonia fertilizer manufacturing
S. Himmelstein | May 06, 2020A sustainable alternative to the current reliance on large-scale manufacturing capacities for fertilizer production is being advanced by MIT researchers. A decentralized approach to ammonia production would help alleviate greenhouse gas emissions and high costs associated with current manufacturing facilities and provide enhanced The nitrogen admitted by the mesh is converted to ammonia through a series of reaction steps mediated by lithium. Source: Nikifar Lazouski et al.access to fertilizer products for remote and rural users.
To substitute for the heat-intensive Haber-Bosch process used to combine hydrogen and nitrogen at large production facilities, the smaller-scale production scheme uses electric current to generate a lithium catalyst, where the reaction takes place. To eliminate reliance on expensive organic solvents, the researchers designed a stainless steel mesh-like electrode that allows nitrogen gas to diffuse through and interact with hydrogen, which is dissolved in ethanol, at the electrode surface. The nitrogen admitted by the mesh is converted to ammonia through a series of reaction steps mediated by lithium.
The laboratory benchtop-sized system, which can consume nitrogen and hydrogen gases from a gas cylinder, can also source hydrogen from water by use of electrolytic techniques. System size and production volume can be increased by coupling modules together, but energy efficiency issues remain to be addressed. The researchers hope to boost process efficiency beyond the current 2%, which is far below the 50 to 80% efficiency of the Haber-Bosch reaction.