Scientists discover greener method to produce ammonia

USA: Scientists in the US claim to have developed a less expensive, more environmentally friendly method of producing ammonia.

Widely used in the production of fertilizer, ammonia is also one of the low GWP “natural” refrigerants vital to global efforts to reduce the environmental impact of refrigeration. Its production, however, is expensive and consumes a lot of energy. 

Researchers at Rice University’s George R Brown School of Engineering in Houston claim to have developed an inorganic method to synthesize ammonia that is both environmentally friendly and can produce the valuable chemical on demand under ambient conditions.

Ammonia is typically produced via the Haber-Bosch process which converts natural gas, LPG or petroleum naphtha into hydrogen gas. The hydrogen is then combined with nitrogen to produce ammonia.

The Brown School of Engineering manipulated molybdenum disulfide, turning it into a catalyst by removing atoms of sulfur and replacing the exposed molybdenum with cobalt. This is said to have allowed the material to mimic the natural organic process bacteria use to create ammonia.

The researchers say the inorganic process will allow ammonia to be produced anywhere it’s needed as a small-scale adjunct to industry.

“The Haber-Bosch process produces a lot of carbon dioxide and consumes a lot of energy,” said co-lead author and Rice graduate student Xiaoyin Tian. “But our process uses electricity to trigger the catalyst. We can get that from solar or wind.”

“The scale is not comparable to well-developed industrials processes, but it can be an alternative in specific cases,” said co-lead author Jing Zhang, a postdoctoral researcher at Rice. “It will allow the production of ammonia where there is no industrial plant, and even in space applications.”