Glycerine: Production route
From murky biodiesel crude to pharmacy-grade liquid
What this tab covers How it is made: the main production routes or, for product families, the main product types and technologies, compared on share of supply, inputs per tonne, plant scale, yield, co-products and unit cost.Almost all glycerine today is a by-product. Biodiesel plants make crude glycerine of about 80% purity; fat splitters make sweetwater that is concentrated to higher-purity crude. Refiners distil crude to technical and USP grades. Synthetic glycerine from propylene via epichlorohydrin, once a large route, has largely closed since the biodiesel boom flooded the market. The reverse process, glycerine to epichlorohydrin and propylene glycol, now absorbs surplus crude.
Routes compared
| Route | Share of supply | Inputs per tonne | Typical scale | Yield | Co-products | Unit cost |
|---|---|---|---|---|---|---|
| Biodiesel by-product (crude 80%) | about 70-75% of world glycerine (indicative) | by-product: about 10 t FAME per t glycerol (indicative) | 10-50 kt a year per biodiesel plant | about 0.1 t per t FAME | not applicable | valued as by-product; crude 80% $419-850/t by region (Argus, Mar 2026) |
| Fat splitting and fatty alcohol by-product (sweetwater) | about 20-25% (indicative) | about 9-10 t oil split per t glycerol (indicative) | integrated with oleochemical plants (Godrej adding 24 kt, 2025) | about 0.1 t per t oil | not applicable | lower impurity than biodiesel crude (indicative) |
| Refining to technical and USP grades | majority of crude is refined (indicative) | about 1.2-1.3 t crude 80% per t refined, steam and activated carbon (indicative) | 20-100 kt a year (indicative) | about 90-95% (indicative) | salt residues, glycerine pitch | refining spread about $430-950/t by region (Argus, Mar 2026, derived) |
| Synthetic glycerine (propylene via epichlorohydrin) | very small today (indicative) | propylene and chlorine (indicative) | legacy plants | high | chloride salts | uncompetitive against by-product glycerine (indicative) |
How each route works
Biodiesel by-product (crude 80%)Glycerine separates from FAME after transesterification; methanol is stripped and the crude is neutralised. It contains about 5-7% salts and some soaps (indicative).
abundant and cheap; impurities, supply set by fuel policy
Argus Glycerine, issue 26-9, 5 Mar 2026 (sample); indicative Fat splitting and fatty alcohol by-product (sweetwater)Glycerine dissolved in the water phase of fat splitting is purified and evaporated; methyl ester plants for fatty alcohols also yield glycerine.
cleaner crude; tied to oleochemical demand
Godrej Industries release, 3 Jul 2025; indicative Refining to technical and USP gradesCrude is filtered, vacuum distilled at low pressure and bleached with activated carbon; USP grades are tested for diethylene and ethylene glycol.
turns low-value crude into consumer grades; energy-intensive
Argus Glycerine, issue 26-9, 5 Mar 2026 (sample) (derived); indicative Synthetic glycerine (propylene via epichlorohydrin)Propylene is chlorinated to allyl chloride and epichlorohydrin, then hydrolysed to glycerine.
very pure; fossil-based and costly
indicative Unit economics are indicative ranges from the sources named; costs move with feedstock and energy prices, plant size and region.