Complete Valorization of Olive Mill Wastewater through an Integrated Process for Poly-3-hydroxybutyrate Production

Abstract

An economical and environmental sustainability of bioplastic production is dependent on the use of low cost and waste C-sources as raw materials. OMW (Olive Mill Wastewater) with its high organic load represents a dangerous polluting waste. Herein the authors present an integrated process for the simultaneous recovery of polyphenols, high value natural antioxidants, production of PHAs (polyhydroxyalkanotes), thermoplastic bio-polymers, in particular of PHB (poly-3-hydroxybutyrate) starting from OMW. The combination of membrane filtration and bacterial digestion of OMW resulted in very high yields of polyphenols (32.5 g/L) and PHB (31.4 mg/L·h) if compared with the state of the art. These results make the technical approach described here effective for reducing the polluting effect of OMW and maximizing the valuable product yield. Moreover the process is readily suitable for an industrial scale PHB production from OMW.