This series of articles on the future of ammonia synthesis began with a report on the NH3 Energy+ conference presentation by Grigorii Soloveichik, Program Director at the US Department of Energy's ARPA-E, who categorized the technologies as being either improvements on Haber-Bosch or electrochemical (with exceptions).
ARPA-E invests in "transformational, high-risk, early-stage research," and recently began funding ammonia synthesis technologies, not to make renewable fertilizer but to produce "energy-dense zero-carbon liquid fuel." This article will introduce the six electrochemical technologies currently in development with funding from ARPA-E.
Last week, in Part 1 of this series on electrochemical ammonia synthesis technologies, I quoted a recent article by researchers at MIT that identified avenues for future research and development. One option was a biomimicry approach, learning from "enzymatic catalysts, such as nitrogenases," which can "either be incorporated into or provide inspiration for the design of electrocatalytic processes."
The nitrogenase enzyme, nature's ammonia synthesis technology, was developed in an iterative innovation process, otherwise known as evolution, that took hundreds of millions of years to reach this level of efficiency. According to one group of electrochemists, who presented their results at the recent NH3 Energy+ conference, nitrogenase produces ammonia in nature with an enviable 75% process efficiency - so it's no surprise that they are basing their industrial technology on it.
Last month's NH3 Energy+ conference featured presentations on a great range of novel ammonia synthesis technologies, including improvements to Haber-Bosch, and plasmas, membranes, and redox cycles. But, in a mark of a conference approaching maturity, members of the audience had at least as much to contribute as the presenters.
This was the case for electrochemical synthesis technologies: while the presentations included updates from an influential industry-academia-government collaboration, led by Nel Hydrogen's US subsidiary, the audience members represented, among others, the new electrochemical ammonia synthesis research lab at Massachusetts Institute of Technology (MIT), and a team from Monash University in Australia. The very next week, Monash published its latest results, reporting an electrochemical process that synthesized ammonia with 60% faradaic efficiency, an unprecedented rate of current conversion at ambient pressure and temperature.
During our NH3 Energy+ Topical Conference, hosted within AIChE's Annual Meeting earlier this month, an entire day of presentations was devoted to new technologies for making industrial ammonia production more sustainable.
One speaker perfectly articulated the broad investment drivers, technology trends, and recent R&D achievements in this area: the US Department of Energy's ARPA-E Program Director, Grigorii Soloveichik, who posed this question regarding the future of ammonia production: "Improvement of Haber-Bosch Process or Electrochemical Synthesis?"