Overview:

Ammonia is one of the most widely utilized chemi­cals in the world and is curr­ently  produced from fossil fuels using the Haber-Bosch process. This process is respon­sible for 1.5 % of global carbon dioxide emis­sions.  However, given the need to reduce the asso­ciated climate impact, ammonia can also be produced elec­tro­che­mi­cally from nitrogen, water and elec­tri­city from rene­wable energy sources. Within the CF04_2 project, tubular cells  that are closed on one side are manu­fac­tured from high-perfor­mance cera­mics. Each of these cells consists of two elec­trodes, which promote the chemical reac­tion on the respec­tive surface, and an elec­tro­lyte that becomes conduc­tive for protons at tempe­ra­tures of 450°C. Hydrogen or water vapor is oxidized on the inner side of the cell where the protons released in the process diffuse through the elec­tro­lyte to the oppo­site elec­trode, where the nitrogen is reduced to ammonia. The elec­tro­lyte is imple­mented as a thin film to increase the effi­ci­ency of the system. 

Important aspects of the project are the mate­rial synthesis and its produc­tion processes as well as the design of the cell inte­gra­tion.  Subse­quently, three cells will be elec­tri­cally inter­con­nected into a tubular stack module and tested with regard to their ammonia produc­tion rates at pres­sures of up to 80 bar. The aim is to demons­trate solid-state ammonia synthesis on a small scale with the pros­pect of being able to inter­con­nect the deve­loped stack modules to form larger modules. This will make ammonia synthesis not only envi­ron­men­tally friendly in the future, but also scalable and ther­e­fore decen­tra­lized.