Catalyst-free valorization of poly-3-hydroxybutyrate to crotonic acid

A novel catalyst-free pyrolysis process of poly-3-hydroxybutyrate (PHB) to crotonic acid (CA) in inert nonpolar solvents was developed. After a simple consecutive process of reaction (210 °C for 5 h in a cyclohexane solvent) and separation (vacuum distillation at 60 °C), CA was obtained with a yield of 89 wt% and a purity of 91%. This work paves a green and sustainable way for the mass production of CA from renewable PHB.