New paradigm for ammonia pursued

The Japanese amino acid maker Ajinomoto is teaming up with Tokyo Institute of Technology professor Hideo Hosono and other partners to commercialize what they say will be the world’s first small-scale, on-site ammonia synthesis system.

Today, essentially all ammonia in commerce is made by the Haber-Bosch process, a century-old catalytic technology that couples hydrogen with nitrogen at high temperature and pressure.

The drawback of the Haber-Bosch process is that it is cost-effective only in large, expensive, generally centralized plants. Hosono’s research group has come up with a new catalyst that, according to the partners, enables efficient ammonia synthesis in small facilities under low-temperature and low-pressure conditions.

The partners aren’t disclosing the specific catalyst. However, a recent research paper from Hosono and colleagues describes catalyzing ammonia production with ruthenium nanoparticles deposited on a calcium aluminate electride.

The Japanese partners have formed a new company, Tsubame BHB, to commercialize the technology. Ajinomoto says it aims to install an ammonia facility by 2021 at one of its amino acid plants, which use fermentation to convert ammonia into products such as glutamic acid.

Researchers have long pursued low-cost, environmentally friendly ammonia production. Recently, two teams of academic chemists presented bioelectrochemical routes to ammonia at the ACS annual meeting in San Francisco. Electrochemical and other processes for ammonia production won funding last December from the Department of Energy’s Advanced Research Projects Agency-Energy arm.

The Haber-Bosch process is quite efficient and to date has been hard to compete against, notes Trevor Brown, a consultant who runs the website Ammonia Industry. “Proven technologies can be funded; unproven technologies have a far harder time attracting funding,” he says.

Nonetheless, several small-scale ammonia projects are advancing, Brown says, and may even open ahead of the Japanese effort. He points to a Siemens project near ­Oxford, England, and a demonstration plant planned by the Swedish firm ­Vattenfall. Both anticipate producing ammonia with hydrogen generated electrochemically from solar or wind power. The ammonia will then be burned as fuel at times when renewable energy comes up short.