Polyurethanes (MDI, TDI, polyols): Emissions
Aniline, nitric acid and PO carry the carbon
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 3.20 t CO2e per t range 2.8-4.0 · indicative (basis: European MDI 2.76, TDI 3.14, long-chain polyol 2.93 and rigid polyol 2.82 t CO2e/t (ISOPA, data year 2018), with about 10% uplift for coal-heavy Asian utilities) Global emissions per year 80.0 Mt CO2e per year 2025 · 3.2 t CO2e/t x 25 Mt (indicative)Per t of polyurethane raw material (isocyanate or polyol), cradle-to-gate. Intensity: ISOPA eco-profiles TDI/MDI and polyols, 2021; uplift indicative. Global total: derived.
Share of footprint by lifecycle phase
Feedstock 84% Production / process 13% Movement 3%Footprint by lifecycle phase
| Phase | Intensity | Share | Main sources of emissions | Notes | Source |
|---|---|---|---|---|---|
| Feedstock | about 2.7 t CO2e per t | 84% | Aniline (74% of MDI GWP), nitric acid and toluene (50% of TDI GWP), PO (74-82% of polyol GWP) | N2O from nitric acid plants is a large hidden share where abatement is missing | ISOPA 2021; derived |
| Production / process | about 0.4 t CO2e per t | 13% | Steam and power for phosgenation and distillation (thermal energy 9-15%, electricity 3-6% of isocyanate GWP) | Higher on coal-based Chinese utilities | ISOPA 2021; indicative |
| Movement | about 0.1 t CO2e per t (indicative) | 3% | ISO tanks and parcel tankers over long distances | indicative | |
| Use | blowing agents and insulation savings | – | HFC blowing agents had GWPs of about 800-1,000 (HFC-245fa, HFC-365mfc); HFOs and pentane are near zero | Rigid PU insulation saves many times its embodied carbon over a building's life (indicative) | indicative |
| End of life | about 2.3 t CO2 per t if incinerated (indicative) | – | Most foam is landfilled or burned | Mattress and foam recycling to polyols (glycolysis, acidolysis) is small but growing | stoichiometry (about 63% carbon), indicative |
Other environmental impacts
Phosgene and isocyanate accident risk; N2O from nitric acid; HFC blowing agents in older foams; formaldehyde in MDA production; foam fires release toxic HCN and CO.
Levers to cut emissions
- N2O abatement at nitric acid plants feeding TDI and MDI
- Renewable power and steam at isocyanate complexes
- Low-GWP blowing agents (HFO, pentane, water/CO2)
- Foam-to-polyol recycling (Dow RENUVA, Covestro and others)
- Bio-based or CO2-based polyols and mass-balance aniline
India
India's footprint is mostly imported: it buys MDI and polyols made in China, Saudi Arabia and Europe. Its own TDI and polyol output is small (about 77 kt/yr polyols, PU Daily 2025). The big Indian lever is in use: rigid PU in cold chain and building insulation under the Energy Conservation Building Code (indicative).
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 |
|---|---|---|---|---|
| CO2-based polyols (Covestro cardyon) | not published; replaces up to about 20% of fossil feed (indicative) | not published | small commercial plant at Dormagen (indicative) | indicative |
| Mattress foam chemical recycling | not published | not published | Dow RENUVA and others at pilot or early commercial scale (PO tile) | indicative |