# Sodium silicate: Emissions

An easy decarbonisation target hidden in soda ash

Source page: https://www.materialinsights.org/chemicals/sodium_silicate/emissions/

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 0.85 t CO2e per t range about 0.5-1.2 · soda ash upstream (about 0.9 t CO2/t x 0.40 t), process CO2 from soda ash (0.17 t), furnace fuel (about 5 GJ gas, 0.28 t), power and dissolving (0.05 t) Global emissions per year 4.00 Mt CO2e per year 2024 · 0.85 t/t x about 5 Mt indicative output

Per t of sodium silicate glass (ratio about 3.3, solid basis), cradle-to-gate, furnace route. Intensity: Derived (indicative). Global total: Derived (indicative).

#### Share of footprint by lifecycle phase
 Feedstock 42% Production / process 52% Movement 6%

#### Footprint by lifecycle phase

| Phase | Intensity | Share | Main sources of emissions | Notes | Source |
|---|---|---|---|---|---|
| **Feedstock** | about 0.36 t CO2e per t | 42% | Soda ash production (Solvay process or trona), sand mining | Natural soda ash from US trona has a lower footprint | Indicative |
| **Production / process** | about 0.44 t CO2e per t | 52% | CO2 released from soda ash in the melt (0.17 t) and furnace fuel | The hydrothermal route avoids the melt but shifts emissions to caustic soda | Stoichiometry; indicative |
| **Movement** | about 0.05 t CO2e per t | 6% | Trucking solutions that are half water | Indicative | Indicative |
| **Use** | none direct | – | Silicate converts to silica or stays in products | Silica-filled tyres cut vehicle fuel use; geopolymers can replace cement | Indicative |
| **End of life** | not applicable | – | Silica is inert | Detergent silicate ends in wastewater as harmless silica | Indicative |

#### Other environmental impacts

Low toxicity; furnace NOx and dust; sand mining impacts.

#### Levers to cut emissions

- Electric or hybrid furnaces using renewable power
- Hydrothermal route with membrane caustic soda from renewable power
- Silica from rice husk ash or other bio-sources instead of sand (indicative)
- Heat recovery from furnace flue gas
- Natural rather than synthetic soda ash

#### India

India's small furnace producers mostly burn fuel oil, coal or gas; no emission data were found. India's large rice husk supply is a possible low-carbon silica source (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 |
|---|---|---|---|---|
| **Hydrothermal silicate from renewable-powered caustic soda** | about 0.3-0.5 t CO2e per t (indicative) | depends on caustic soda price | commercial route; low-carbon power use not documented in sources used | Indicative |
| **Bio-silica from rice husk ash** | low (indicative) | not published | small commercial and pilot plants in Asia (indicative) | Indicative |

 For a climate investor Silicate is a modest emitter, but it enables two climate products: precipitated silica for low-rolling-resistance tyres and activators for geopolymer cements. Opportunities include electrified furnaces, hydrothermal plants beside chlor-alkali sites with green power, and rice husk silica in India. Scale depends on tyre makers and cement firms adopting these materials; Evonik, PQ, Qemetica and Indian tyre-silica suppliers are relevant.

## Other sections

- [Summary](https://www.materialinsights.org/chemicals/sodium_silicate/index.md)
- [Overview](https://www.materialinsights.org/chemicals/sodium_silicate/overview/index.md)
- [Correlation](https://www.materialinsights.org/chemicals/sodium_silicate/correlation/index.md)
- [Production route](https://www.materialinsights.org/chemicals/sodium_silicate/routes/index.md)
- [Production](https://www.materialinsights.org/chemicals/sodium_silicate/production/index.md)
- [Feedstocks](https://www.materialinsights.org/chemicals/sodium_silicate/feedstocks/index.md)
- [Cycles](https://www.materialinsights.org/chemicals/sodium_silicate/cycles/index.md)
- [Trading](https://www.materialinsights.org/chemicals/sodium_silicate/trading/index.md)
- [Movement](https://www.materialinsights.org/chemicals/sodium_silicate/movement/index.md)
- [Regulation](https://www.materialinsights.org/chemicals/sodium_silicate/regulation/index.md)
- [Characteristics](https://www.materialinsights.org/chemicals/sodium_silicate/characteristics/index.md)
- [Relationships](https://www.materialinsights.org/chemicals/sodium_silicate/links/index.md)