# How much N2O does an adipic acid plant emit?

Canonical: https://senseible.earth/answers/adipic-acid-plant-n2o-emissions

Adipic acid is made by oxidising a cyclohexanone and cyclohexanol mix with nitric acid, which releases nitrous oxide. The IPCC 2006 default is 300 kg N2O per tonne without abatement, about 82 tonnes CO2e at a GWP of 273. Abatement units destroy most of it.

## Where it comes from

The nitric acid oxidation step forms nitrous oxide, which leaves with the off-gas. Without abatement it is by far the largest emission source, much larger than fuel.

## What to record

- Tonnes of adipic acid produced each month.
- N2O measured in the off-gas, or the abatement unit's destruction rate and running hours.
- Fuel and electricity for the plant, as Scope 1 and 2 CO2.

## How to report

N2O is Scope 1. Convert it with the AR6 100-year GWP of 273 and state the hours the abatement unit was off, since a few days of bypass can outweigh a month of normal running.

## Worked example (illustrative figures)

- Production: 10,000 tonnes of adipic acid.
- Without abatement: 10,000 × 300 kg = 3,000 tonnes N2O.
- With 90 percent destruction: 300 tonnes N2O remain.
- 300 × 273 = 81,900 tonnes CO2e.

## What Senseible does here

Senseible reads bills, fuel invoices and production records into dated, fingerprinted records, so the figure you send a buyer can be traced to its documents.

- [Nitric acid plant N2O](https://senseible.earth/answers/nitric-acid-plant-n2o-emissions)
- [Caprolactam plant N2O](https://senseible.earth/answers/caprolactam-plant-n2o-emissions)
- [Fertiliser N2O calculation](https://senseible.earth/answers/fertiliser-n2o-emissions-calculation)

Sources: [IPCC 2006 Guidelines for National Greenhouse Gas Inventories](https://www.ipcc-nggip.iges.or.jp/public/2006gl/), [IPCC AR6 Working Group I](https://www.ipcc.ch/report/ar6/wg1/), [GHG Protocol Corporate Standard](https://ghgprotocol.org/corporate-standard)

Last reviewed 2026-10-22.