Ammonium sulphate
A low-cost nitrogen-plus-sulphur fertiliser, mostly a by-product of nylon and coke making, now dominated by record Chinese exports.
Commodity chemicals · Nitrogen & phosphate chemicals · No. 21
- Single chemical
- Feedstock: Minerals and salts
- about 32.9 Mt (2024); China alone exported about 21.4 Mt in 2025, so the world total may be understated
- 0.5 t CO₂e per t
- HS 310221
Much of this cheap fertiliser is leftover from making nylon, and China exported over 21 Mt of it in 2025.
Chart: Illustration: Ammonium sulphate
Where it comes from
Chart: Map of where it comes from
Most ammonium sulphate is a by-product of caprolactam for nylon, coke ovens and flue-gas scrubbing; only about 15% is made on purpose from ammonia and acid.
Three things to know
- Ammonium sulphate carries 21% nitrogen and 24% sulphur, and demand is rising as farm soils run short of sulphur.
- Because supply follows nylon and steel output, it does not shrink when prices fall, so prices halved in 2023.
- In February 2026 it sold for $277/t in Europe, cheap per tonne but about $1,320 per tonne of nitrogen.
The journey
- 1 Nylon plantsCaprolactam making leaves AS behind
- 2 Coke ovensAmmonia scrubbed from gas with acid
- 3 Direct synthesisAmmonia plus sulphuric acid, 15%
- 4 Crystals or granulesGranules blend into NPK fertiliser
- 5 ExportShipped from China to Brazil, Europe