Yttrium: Emissions
Why yttrium's footprint is understated at the oxide stage
Why yttrium's footprint is understated at the oxide stage What this tab covers The greenhouse-gas footprint of the commodity at a global level, split by lifecycle phase: extraction (or farming), refining and processing, movement, usage, and recycling or end of life. Intensities are per unit of product; the global total combines intensity with world output. Also covers other environmental impacts and the main levers to cut emissions. Emission intensity 26.0 t CO2e per t range 18.8-33.1 · cradle-to-gate primary data from Chinese heavy rare-earth sites, ending at mixed oxide; solvent-extraction separation to pure Y2O3 is outside the boundary and would add to it. Midpoint taken Global emissions per year 0.33 Mt CO2e per year 2025 · about 26 t CO2e/t x 12,500 t Y2O3 (midpoint of USGS 10,000-15,000 t), excluding separation and co-produced rare earths (derived, indicative)Per t of mixed heavy rare-earth oxide (90% purity) from ion-adsorption clays, yttrium-rich, cradle-to-gate; excludes separation into pure Y2O3. Intensity: Deng & Kendall 2019, International Journal of Life Cycle Assessment 24:1643. Global total: Derived from Deng & Kendall 2019 and USGS MCS 2026.
Share of footprint by lifecycle phase
Extraction 62% Refining / processing 38%Footprint by lifecycle phase
| Phase | Intensity | Share | Main sources of emissions | Notes | Source |
|---|---|---|---|---|---|
| Extraction | 10.4-21.8 t CO2e/t: in-situ leaching of clays with ammonium sulfate | 62% | ammonium sulfate supply (7.6-19.0 t CO2e/t on its own) | Leachant use is the biggest single driver | Deng & Kendall 2019 |
| Refining / processing | precipitation and pH adjustment 5.4-8.3 t; calcination 3.0 t CO2e/t | 38% | ammonium bicarbonate, oxalic acid, electricity (5.8 t CO2e/t) | Separation by solvent extraction into individual oxides is extra and not quantified here | Deng & Kendall 2019 |
| Movement | small | – | trucking of Burmese concentrate to China, container export of oxide | Not material | Qualitative |
| Usage | no direct emissions | – | ceramics, coatings, lasers, phosphors | Enabling: yttria-stabilised zirconia in thermal barrier coatings and fuel cells raises turbine and fuel-cell efficiency | Qualitative |
| Recycling / end of life | insignificant: EU end-of-life recycling input rate about 1% | – | some phosphor recovery from lamps | Yttrium in ceramics and coatings is not recovered | USGS MCS 2026; EU CRM 2023 |
Other environmental impacts
In-situ leaching of ion-adsorption clays leaves ammonium and heavy metals in soils and streams; unregulated mining in Burma's Kachin State has caused deforestation and water pollution.
Levers to cut emissions
- Cut or recycle ammonium sulfate leachant, the main source of emissions, or switch to magnesium sulfate leaching
- Low-carbon electricity for precipitation, calcination and separation
- Recover yttrium from wastes such as phosphogypsum and lamp phosphors
- Enforce leaching controls to protect groundwater at clay sites
India
India's rare earths come from IREL's monazite processing, which is low in yttrium, so India's yttrium footprint is mainly embedded in imported Chinese oxide (India produced 2,900 t REO in 2025e, USGS).
Emission figures are indicative global averages from the life-cycle studies named; actual footprints vary widely by site, energy mix and method.