Agriculture relies heavily on the use of fertilizers to grow the crops that feed a growing world population. Nitric acid plays a prominent role as a key ingredient. Nitric acid itself is produced via the oxidation of ammonia: this process however generates nitrous oxide (N₂O) as a by-product.

N₂O – commonly referred to as laughing gas – contributes to global warming over 300 times as badly as carbon dioxide (CO₂). N₂O emissions in 2003 accounted for about 17 per cent of all greenhouse gas emissions from industrial sources in the European Union, according to European Environmental Agency statistics. Every year, around 1.2 million tons of N₂O are released from the smoke stacks of the acid producers. In relative terms, this is equal to the CO₂ climate pollution that around 80 million cars inflict on the atmosphere.

Innovative secondary catalysts using small amounts of precious metal to reduce nitrous oxide emissions during the fertilizer production by up to 90 per cent. There are around 600 fertilizer plants worldwide, and all work on the same basic principle: Ammonia and air are guided over platinum gauzes at 900 °C, where the gases break down and recombine to a certain extent, forming useful compounds such as nitric acid, from which the familiar nitrate fertilizers are later produced.

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