# Chlorine

Chlorine is a toxic gas made by passing electricity through salt brine; it underpins PVC, polyurethanes, titanium dioxide and safe drinking water.

Source page: https://www.materialinsights.org/chemicals/chlorine/

Commodity chemicals · Acids & alkalis · No. 7

- Single chemical
- Feedstock: Minerals and salts
- about 80 Mt of chlorine a year (2025, indicative, derived); Euro Chlor and the World Chlorine Council publish no world total, and commercial figures of about 92-97 Mt (P Plus 2024; Statista 2022) appear to be capacity-type estimates
- 1.0 t CO₂e per t
- HS 280110
 Commodity chemicals · Acids & alkalis · Foundation · Matter

In October 2025 Chinese chlorine makers were paying customers to take their toxic gas away.

Chart: Illustration: Chlorine

##### Where it comes from

Chart: Map of where it comes from

Electricity splits salt brine into chlorine, caustic soda and a little hydrogen; membrane cells use about 2.5-2.8 MWh per tonne of chlorine.

##### Three things to know

1. Chlorine and caustic soda come out together in a fixed 1 to 1.13 ratio, so plants must find buyers for both.
2. Electricity is about half the cash cost; in 2022 a European plant's cost was over twice the Americas' roughly $590 per unit.
3. Chlorine is hard to store or ship, so only about 1-2% of output crosses borders; it travels hidden inside PVC instead.

##### The journey

1. 1 **Salt brine**About 1.7 t salt per tonne
2. 2 **Purification**Calcium and magnesium cut to ppb
3. 3 **Electrolysis**Brine split; caustic and hydrogen alongside
4. 4 **Drying**Dried with sulphuric acid, then compressed
5. 5 **Derivatives**Piped straight into PVC, MDI, HCl
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## Other sections

- [Overview](https://www.materialinsights.org/chemicals/chlorine/overview/index.md)
- [Correlation](https://www.materialinsights.org/chemicals/chlorine/correlation/index.md)
- [Production route](https://www.materialinsights.org/chemicals/chlorine/routes/index.md)
- [Production](https://www.materialinsights.org/chemicals/chlorine/production/index.md)
- [Feedstocks](https://www.materialinsights.org/chemicals/chlorine/feedstocks/index.md)
- [Cycles](https://www.materialinsights.org/chemicals/chlorine/cycles/index.md)
- [Trading](https://www.materialinsights.org/chemicals/chlorine/trading/index.md)
- [Movement](https://www.materialinsights.org/chemicals/chlorine/movement/index.md)
- [Regulation](https://www.materialinsights.org/chemicals/chlorine/regulation/index.md)
- [Characteristics](https://www.materialinsights.org/chemicals/chlorine/characteristics/index.md)
- [Emissions](https://www.materialinsights.org/chemicals/chlorine/emissions/index.md)
- [Relationships](https://www.materialinsights.org/chemicals/chlorine/links/index.md)