Bio-acrylic acid

Acrylic acid is a C3 unsaturated carboxylic acid produced globally at multimillion-tonne annual scale, almost entirely from fossil propylene via two-step catalytic oxidation through acrolein, and used downstream for superabsorbent polymers in hygiene products, polymer emulsions for paints and coatings, and acrylate ester monomers for adhesives, textiles and pressure-sensitive films. Two competing renewable routes are now commercialising in parallel. Arkema launched bio-based Ethyl Acrylate produced entirely from bioethanol at its Carling (France) acrylic monomer facility in October 2024, achieving 40% bio carbon content and up to 30% reduction in product carbon footprint, and BASF switched its entire ethyl acrylate portfolio to a bio-based grade in August 2024 followed by a 2026 collaboration with Avery Dennison on renewable-attributed butyl acrylate and 2-ethylhexyl acrylate. A separate value chain aims at the molecule itself rather than its esters: Cargill’s long-running 3-hydroxypropionic acid (3-HPA) platform, advanced in a January 2026 Nature Communications paper on the acid-tolerant yeast Issatchenkia orientalis SD108 engineered through the β-alanine pathway with up to eight copies of the PAND gene, would convert fermentatively produced 3-HPA to acrylic acid by catalytic dehydration; Genomatica’s March 2026 paper in Microbial Cell Factories established Saccharomyces cerevisiae as a host for direct acrylic-acid fermentation, identifying the β-alanine route as most promising and achieving around 30 mg/L AA in batch shake-flask experiments after ACH1-knockout work. No Chinese commercial bio-acrylic-acid originator cleared source confirmation as of 2026.

The key directions of bio-acrylic acid are:

1. 3-Hydroxypropionic acid (3-HPA) fermentation route (3-Hydroxypropionic Acid Fermentation): microbial production of the direct AA precursor 3-HPA via engineered acid-tolerant yeast, followed by catalytic dehydration to acrylic acid — Cargill’s I. orientalis SD108 β-alanine-pathway platform.
2. Direct acrylic-acid fermentation (Direct Acrylic Acid Fermentation): engineering yeast to excrete acrylic acid itself rather than a precursor, bypassing the chemical dehydration step — Genomatica’s S. cerevisiae host with ACH1-knockout tolerance mechanism.
3. Bioethanol-derived acrylate esters (Bioethanol-to-Acrylate Route): replacing fossil propylene with bioethanol as the upstream feedstock for the conventional acrolein-oxidation route, producing drop-in bio-based acrylate esters — Arkema (Carling) and BASF (Ludwigshafen / Freeport).
4. Pilot-to-commercial scale-up (Bio-Acrylic Acid Scale-Up): moving fermentative AA routes from milligram-per-litre laboratory titres toward the volumes and economics required to displace propylene-derived acrylic acid — the common bottleneck across Cargill and Genomatica’s programmes.

Sectoral value chain#

[sugars / bioethanol / glycerol feedstock] ──> [microbial fermentation or bioethanol-to-acrolein conversion]
                                                            │
                                              (intermediates: 3-HPA, acetaldehyde, acrolein)
                                                            │
                                                            ▼
[bio-based acrylate ester] <─── [esterification] <─── [catalytic dehydration to acrylic acid]
                                                            │
                                                            ▼
                                [superabsorbent polymers, coatings, adhesives]

Value chain levels#

Cross-cutting technologies of the sector:

• β-alanine biosynthetic pathway (3-Hydroxypropionic Acid Fermentation): the metabolic route identified as optimal for both 3-HPA and direct AA production, converting aspartate through PAND (aspartate decarboxylase), BAPAT and YDFG to the target C3 acid.
• Acid-tolerant yeast host engineering (Direct Acrylic Acid Fermentation): use of low-pH-tolerant yeasts (I. orientalis SD108, ACH1-knockout S. cerevisiae) to enable product accumulation in acid form rather than as a neutralised salt.
• Bioethanol-to-acrylate drop-in chemistry (Bioethanol-to-Acrylate Route): integration of bioethanol feedstock into the conventional acrolein-oxidation process to produce molecularly identical, drop-in bio-based acrylate esters.

The stack spans two distinct renewable-AA value chains: microbial fermentation toward the molecule itself (still pre-commercial) and bioethanol-fed drop-in acrylate ester production (already commercial).

1. β-alanine-pathway 3-HPA fermentation (3-Hydroxypropionic Acid Fermentation):
   • Cargill’s January 2026 Nature Communications paper engineered Issatchenkia orientalis SD108 with a genetic toolbox (episomal plasmids, promoter/terminator library, multiplex CRISPR deletion, landing-pad multi-copy integration) and identified the β-alanine pathway as optimal, with PAND (aspartate decarboxylase) rate-limiting at up to eight integrated copies and balanced PYC (pyruvate carboxylase) and AAT (aspartate aminotransferase) pushing flux toward 3-HPA at low pH.
2. Direct acrylic-acid yeast fermentation (Direct Acrylic Acid Fermentation):
   • Genomatica’s March 2026 Microbial Cell Factories paper established Saccharomyces cerevisiae as a host for direct AA production, identifying the β-alanine route as most promising, linking AA tolerance to mitochondrial genes ACH1 and ETR1, and achieving around 30 mg/L AA in batch shake-flask experiments after ACH1 knockout reduced AA-CoA accumulation and AA degradation.
3. Bioethanol-derived drop-in acrylates (Bioethanol-to-Acrylate Route):
   • Arkema’s October 2024 Carling launch and BASF’s August 2024 portfolio switch both produce drop-in bio-based ethyl acrylate by replacing fossil-derived propylene feedstock with bioethanol, yielding a molecularly identical ester with verifiable bio carbon content (40% BCC at Arkema) and quantified carbon-footprint reduction (up to 30% PCF).
4. Pilot-to-commercial scale-up (Bio-Acrylic Acid Scale-Up):
   • Across Cargill and Genomatica, the shared technical challenge is moving from milligram-per-litre laboratory titres toward the tonne-scale production volumes and cost positions required to displace fossil propylene in commodity acrylic acid markets, a gap that the commercial drop-in acrylate producers (Arkema, BASF) have already bridged via the bioethanol route.