Scale-Up of the Downstream Process for Polyhydroxyalkanoate Copolymer P(HB‑co-HHx) Extraction with Nonhalogenated Solvents

Biobased and biodegradable polyhydroxyalkanoates (PHAs) are promising alternatives to common plastics. Due their high production costs, only a minimal share of global plastic is composed PHA. A major contributor the costs minimizing potential occupy larger market downstream process. To obtain recovery yields pure products, most approaches rely on large amounts solvents. While short-chain-length PHA (scl-PHA) poorly soluble in nonhalogenated solvents, medium-chain-length (mcl-PHA) was shown be In this study, an approach recover poly(hydroxybutyrate-co-hydroxyhexanoate) with acetone 2-propanol scaled up 30-fold 300 g lyophilized cells per cycle. High purities 90–100 % were reached from extractions at moderate temperatures 30–58 °C. two-stage extractions, 100 recovered, while molecular weight not reduced. Solvents recovered by distillation concentration step after precipitation. Furthermore, material properties analyzed. bottom had increased HHx content compared first second using solvents low purity, indicating efficient precipitation during 2-stage