# Acrylic acid: Production route

Two reactors in a row, and why propane never caught on

Source page: https://www.materialinsights.org/chemicals/acrylic_acid/routes/

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 acrylic acid is made by two-stage vapour-phase oxidation of propylene, licensed by BASF, Nippon Shokubai, Mitsubishi Chemical, LG Chem and Arkema. Propane oxidation in one step has been researched but not commercialised. Bio-based routes via glycerine to acrolein, 3-hydroxypropionic acid (3-HP) from sugar, or lactic acid dehydration have reached pilot or demonstration scale only. The old acetylene (Reppe) route has disappeared.

#### Routes compared

| Route | Share of supply | Inputs per tonne | Typical scale | Yield | Co-products | Unit cost |
|---|---|---|---|---|---|---|
| **Two-stage propylene oxidation** | over 99% of global capacity (indicative) | about 0.7 t propylene and 3-4 t air per t AA (indicative) | 80-320 kt/yr per train; IOCL Dumad 90 kt/yr (Tecnimont 2020) | about 85-90% on propylene (indicative) | acetic acid, CO2, water; steam export | propylene about 60-70% of cash cost (indicative) |
| **Esterification to acrylate esters** | about 50% of AA is converted this way (CMA 2026) | about 0.56 t AA and 0.58 t n-butanol per t butyl acrylate (stoichiometric) | 50-200 kt/yr ester units; IOCL Dumad butyl acrylate 150 kt/yr | above 95% (indicative) | water | not published |
| **Glacial AA and SAP** | about one-third of AA (indicative) | about 0.75 t AA and 0.3 t caustic soda per t SAP (indicative) | 60-200 kt/yr SAP lines | high | minimal | not published |
| **Bio-based acrylic acid (3-HP, glycerine, lactic acid)** | negligible | not published | pilot or demonstration | not published | water | not competitive at 2025 prices (indicative) |

#### How each route works
**Two-stage propylene oxidation**

Propylene, air and steam are fed through two fixed-bed tubular reactors in series. The first makes acrolein, the second acrylic acid. Heat from the strongly exothermic reactions is recovered as steam. Products are absorbed in water or solvent and purified.

Mature and efficient; exposed to propylene prices.
 Tecnimont 2020; indicative **Esterification to acrylate esters**

Crude AA reacts with butanol, 2-ethylhexanol, ethanol or methanol over acid catalysts. Esters are distilled and stabilised with inhibitors.

Ties AA to oxo-alcohol supply.
 Tecnimont 2020; Chemical Market Analytics 2026 **Glacial AA and SAP**

Crude AA is crystallised or distilled to glacial grade, neutralised with caustic soda and polymerised with cross-linkers into SAP granules.

Higher value; SAP is a concentrated market (Nippon Shokubai, BASF, LG Chem, Evonik, Sumitomo Seika).
 indicative **Bio-based acrylic acid (3-HP, glycerine, lactic acid)**

Sugars are fermented to 3-HP or lactic acid and dehydrated, or glycerine is dehydrated to acrolein and oxidised.

Renewable carbon for 'bio-diapers', but unproven at scale; BASF, Cargill and Novozymes ended a joint 3-HP effort in 2015 (indicative).
 indicative Unit economics are indicative ranges from the sources named; costs move with feedstock and energy prices, plant size and region.

## Other sections

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