Sodium silicate: Emissions

An easy decarbonisation target hidden in soda ash

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.