Molybdenum: Emissions
Why molybdenum's footprint varies fivefold
Why molybdenum's footprint varies fivefold 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 5.70 t CO2e per t range 5-25 per t Mo (3.2-14.8 per t of 60% FeMo) · cradle-to-gate; 5.7 is the ecoinvent-based global average per kg Mo; the range spans a copper by-product case (low) to a primary mine case (high) for ferromolybdenum Global emissions per year 1.50 Mt CO2e per year 2025 · 5.7 t CO2e/t x 260,000 t Mo (derived); 1.4-6.4 Mt on the 5-25 t rangePer t of molybdenum contained (cradle-to-gate; ferromolybdenum basis in the phase data). Intensity: Nuss & Eckelman 2014 (indicative); J. Sustainable Metallurgy 2020, FeMo process model. Global total: USGS MCS 2026; derived.
Footprint by lifecycle phase
| Phase | Intensity | Share | Main sources of emissions | Notes | Source |
|---|---|---|---|---|---|
| Extraction | 0.46-12.06 t CO2e/t FeMo, 14-81% of the total | – | diesel for mining low-grade porphyry ore, grinding and flotation power | The primary-mine case has the highest share (81%), mostly diesel; by-product supply carries only a share of copper mining emissions under allocation rules | J. Sustainable Metallurgy 2020 |
| Refining / processing | roasting near zero direct fuel in ideal conditions; smelting emissions mostly from FeSi, aluminium and lime inputs | – | upstream ferrosilicon and aluminium reductants (over 73% of smelting emissions), furnace electricity | Roasting MoS2 releases SO2, which is captured as sulphuric acid at modern roasters | J. Sustainable Metallurgy 2020 |
| Movement | less than 6% of the total | – | trucking and shipping concentrate to roasters and FeMo to steel mills | The smallest stage in the FeMo model | J. Sustainable Metallurgy 2020 |
| Usage | not applicable | – | No direct emissions in use; the metal sits inside steel or alloys for decades. | Mo enables lighter high-strength steel, corrosion-proof plant and refinery hydrodesulphurisation catalysts that cut SO2 from fuels | content_v2 uses |
| Recycling / end of life | lower than primary (no sourced figure) | – | remelting alloy, stainless and superalloy scrap; reprocessing spent catalysts | Recycled Mo may be up to 30% of US apparent supply, and EU end-of-life recycling input is 30% | USGS MCS 2026; EU CRM 2023 |
Other environmental impacts
Large porphyry mines create tailings dams and use much water in arid Chile and Peru; roasters must control SO2 (indicative).
Levers to cut emissions
- Electrify mine haulage and use renewable power at Andean mines; diesel drives the high-emission primary case
- Recover more by-product molybdenite at copper mines, which carries a smaller allocated footprint
- Lower-carbon ferrosilicon and aluminium reductants for FeMo smelting (over 73% of smelting emissions)
- Raise scrap and spent catalyst recycling (30% EU end-of-life input)
India
India has no molybdenum mining and imports oxide and ferromolybdenum for its steel and stainless industry, so its footprint is embodied in imports from China, Chile and Korea; no Indian volume was found (USGS; content_v2).
Emission figures are indicative global averages from the life-cycle studies named; actual footprints vary widely by site, energy mix and method.