Nitric acid: Emissions

The cheapest industrial climate fix most people never heard of

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 1.75 t CO2e per t range about 0.7-3.2 · ammonia at 0.285 t x 2.4 t CO2/t (IEA global average) plus N2O: about half of plants unabated at about 7 kg N2O/t and half abated to about 1 kg/t, at GWP 273 Global emissions per year 115 Mt CO2e per year 2022 · 1.75 t/t x 65.5 Mt; about 70 Mt from N2O and 45 Mt from ammonia

Per t of 100% HNO3, cradle-to-gate. Intensity: Derived from IEA Ammonia Technology Roadmap (2021), IPCC defaults via KBR, Clariant (2022) (indicative). Global total: Derived (indicative); Clariant puts N2O from nitric and adipic acid together at about 100 Mt CO2e a year.

Share of footprint by lifecycle phase

Feedstock 39% Production / process 60% Movement 1%

Footprint by lifecycle phase

Phase	Intensity	Share	Main sources of emissions	Notes	Source
Feedstock	about 0.68 t CO2e per t	39%	Ammonia from gas (about 1.8-2.4 t CO2/t NH3) or coal (higher)	Low-carbon ammonia cuts this phase	IEA Ammonia Technology Roadmap 2021 (indicative)
Production / process	about 1.05 t CO2e per t (fleet average); 1.5-2.5 t unabated; under 0.3 t with tertiary abatement	60%	N2O from ammonia oxidation	The plant is a net energy exporter, so CO2 from energy is small	KBR; Heraeus; Calyx Global
Movement	about 0.02 t CO2e per t	1%	Short road and rail moves	Most acid is used on site	Indicative
Use	outside the cradle-to-gate total	–	Nitrate fertilisers	Field N2O from nitrogen fertiliser is a large separate source; adipic acid making emits N2O if unabated	Indicative
End of life	not applicable	–	Acid is consumed	Nitrate run-off causes water pollution	Indicative

Other environmental impacts

NOx emissions (acid rain, smog), nitrate run-off from fertilisers, and explosion risk of AN.

Levers to cut emissions

Tertiary N2O abatement on every plant: 95-98% removal (KBR) at $1-5 per t CO2e (NACAG)
Secondary catalysts under the gauze, up to 95% removal (Clariant, Heraeus)
Low-carbon ammonia feed (electrolytic or with CCS)
Up to 180 Mt CO2e a year of additional abatement potential globally (NACAG, 2021)

India

India is not among the countries named in NACAG's commitments (IKI, 2021), and the abatement status of Indian plants was not found; Indian N2O abatement is a candidate for the domestic carbon market and Article 6 deals (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
Ostwald plant with tertiary N2O abatement	about 0.7-0.9 t CO2e per t (ammonia only)	about $1-5 per t CO2e abated (NACAG)	Standard in the EU; Clariant catalyst on more than 45 plants abating over 20 Mt CO2e a year (2022)	Agro-Chemistry (2022); NACAG
Green nitric acid from electrolytic ammonia	near zero with abatement	set by green ammonia cost (indicative several hundred $ per t NH3)	Small projects linked to green ammonia in Europe (indicative)	Indicative

For a climate investor N2O abatement at nitric acid plants is one of the cheapest industrial emission cuts, at $1-5 per t CO2e, and more than 20 million credits have been issued for it (Calyx Global). The opportunity is funding catalysts at unabated plants in India, Southeast Asia, Africa and Latin America, which needs a durable carbon price, a compliance rule or credible credits. Clariant, Heraeus, thyssenkrupp Uhde, Johnson Matthey and Casale supply the technology.