Scientists use lightning to make ammonia out of thin air

Researchers at the University of Sydney have exploited human manufacturing lightning to develop a more effective method of generation of ammonia – one of the most important chemicals in the world. Ammonia is also the main ingredient of fertilizers which represent almost half of all global food production.

Research was published in International edition of Angewandte Chemie.

The team has successfully developed a simpler method to produce ammonia (NH₃) in the form of gas. The previous efforts of other laboratories have produced ammonia in a solution (ammonium, NH₄⁺), which requires more energy and processes to transform it into a final gas product.

The current method for generating ammonia, the Haber-Bosch process, has a large climate cost, leaving a huge carbon footprint. This must also occur on a large scale and close to inexpensive natural gas sources to make it profitable.

The chemical process that has nourished the world and the Sydney team seek to revolutionize it

Natural ammonia (mainly in the form of bird excrement) was once raised on demand, it fueled wars.

The invention of the Haber-Bosch process in the 19th century made human ammonia possible and revolutionized modern agriculture and industry. Currently, 90% of the global production of ammonia is based on the Haber-Bosch process.

“The appetite of industry for ammonia is only growing. Over the past decade, the global scientific community, including our laboratory, wanted to discover a more lasting means of producing ammonia which is not based on fossil fuels.

“Currently, the generation of ammonia requires centralized production and long -distance transportation of the product. We need a low -cost, decentralized and scalable ammonia” “said the principal researcher, Professor PJ Cullen of the School of Chemical and Biomolecular Engineering at the University of Sydney.

His team has been working on “AMMONIA GREEN” production for six years.

“In this research, we have successfully developed a method that allows air to be converted into ammonia in its gaseous form using electricity. A huge step towards our objectives.”

Ammonia contains three hydrogen molecules, which means that it can be used as an effective support and hydrogen source as a source of energy, even potentially as an effective means of storage and transport of hydrogen. The bodies of the industry have found that they can access hydrogen by “crunching” ammonia to separate the molecules to use hydrogen.

Ammonia is also a solid candidate for use as a carbon -free fuel due to its chemical composition. This has attracted the interest of the maritime transport industry, which is responsible for around 3% of all global greenhouse gas emissions.

Cracking a chemical enigma

The new method of Professor Cullen’s team to generate ammonia works by exploiting plasma power, electrifying or exciting air.

But the star is an electrolyzer based on membrane, a box of apparently non -descriptive silver, where the conversion of gas ammonia occurs.

During the Haber-Bosch process, ammonia (NH₃) is made by combining nitrogen (n₂) and hydrogen (h₂) gases at high temperatures and pressure in the presence of a catalyst (a substance that accelerates a chemical reaction).

The plasma -based method developed by the teacher Cullen team has developed uses electricity to excite nitrogen and oxygen molecules in the air. The team then passes these molecules excited to the electrolyzer based on membrane to convert the molecules excited in ammonia.

The researchers said it was a simpler path for ammonia production.

Professor Cullen said that the results report a new phase to make the AMMONAC Green possible. The team is now working to make the method more economical and competitive in relation to the Haber-Bosch process.

“This new approach is a two -step process, namely the combination of plasma and electrolysis. We have already made the plasma component viable in terms of energy efficiency and scalability.

“To create a more complete solution to a sustainable ammonia productive, we must push the energy efficiency of the electrolying component,” said Professor Cullen.