Caprolactam: Emissions
Nitrous oxide makes this a surprisingly heavy footprint
What this tab covers The greenhouse-gas footprint per tonne, split by lifecycle phase (feedstock, production, movement, use, end of life), the global total, other environmental impacts, levers and low-carbon routes, India's position, and where the investment opportunity lies. Emission intensity 4.00 t CO2e per t range 2.5-6.5 · indicative (basis: about 0.9 t benzene x 1.86 t CO2e/t from Plastics Europe, plus ammonia and process energy, plus N2O from ammonia oxidation where unabated) Global emissions per year 28.0 Mt CO2e per year 2024 · 4.0 t CO2e/t x 7 Mt (indicative)Per t of caprolactam, cradle-to-gate. Intensity: derived and indicative; Plastics Europe Public LCI Database via Climatiq for benzene. Global total: derived.
Share of footprint by lifecycle phase
Feedstock 50% Production / process 48% Movement 2%Footprint by lifecycle phase
| Phase | Intensity | Share | Main sources of emissions | Notes | Source |
|---|---|---|---|---|---|
| Feedstock | about 2.0 t CO2e per t (benzene, ammonia, hydrogen, H2O2, oleum) | 50% | Benzene 1.67 t CO2e; ammonia from gas or coal | Coal-based ammonia and hydrogen in China raise it | derived; indicative |
| Production / process | about 1.9 t CO2e per t (indicative) | 48% | Steam and power; N2O from hydroxylamine production in Raschig and HPO routes | N2O abatement catalysts can remove most of it | indicative |
| Movement | about 0.05-0.1 t CO2e per t (indicative) | 2% | Heated container shipping | indicative | |
| Use | not applicable | – | Intermediate | n/a | |
| End of life | about 2.3 t CO2 per t nylon 6 if incinerated (63.7% carbon) | – | Nylon textiles mostly landfilled or burnt | Nylon 6 can be depolymerised back to caprolactam (e.g. Aquafil Econyl) | stoichiometry |
Other environmental impacts
N2O, a greenhouse gas about 273 times CO2 over 100 years (IPCC AR6); large ammonium sulphate by-product; abandoned fishing nets as marine litter.
Levers to cut emissions
- N2O abatement catalysts on ammonia oxidation
- Switching to ammoximation or vapour-phase Beckmann to cut by-product and energy
- Low-carbon ammonia and hydrogen
- Depolymerising nylon 6 waste back to caprolactam
India
GSFC is India's only producer; its N2O abatement status was not found in sources reached.
Emission figures are indicative global averages from the life-cycle studies named; actual footprints vary widely by site, energy mix and method.Low-carbon routes
| Route | Intensity | Cost premium | Status | Source |
|---|---|---|---|---|
| Nylon 6 depolymerisation to caprolactam (Aquafil Econyl) | not published in sources reached | premium product pricing (indicative) | commercial at Ljubljana, Slovenia (indicative) | indicative |
| Bio-based caprolactam (e.g. from sugars via lysine) | not published | large | pilot (indicative) | indicative |