Integrated process for the production of polyhydroxyalkanoates and bioethanol from lignocellulose hydrolyzate

An integrated process for the production of polyhydroxyalkanoates (PHAs) and bioethanol from lignocellulosic hydrolyzate, the process including the following steps:

• (a) feeding at least a part of said lignocellulosic hydrolyzate to a first fermentation device in the presence of at least one microorganism capable of using sugars with six carbon atoms (C6) and organic acids, obtaining a first fermentation broth;
• (b) subjecting the first fermentation broth obtained in said step (a) to separation obtaining an aqueous suspension of cellular biomass comprising at least one polyhydroxyalkanoate (PHA) and an aqueous phase comprising sugars with five carbon atoms (C5) in a quantity greater than or equal to 10 g/L;
• (c) optionally, feeding at least a part of the aqueous phase obtained in said step (b) to a second fermentation device in the presence of at least one microorganism capable of using both sugars with five carbon atoms (C5) and sugars with six carbon atoms (C6), obtaining a second fermentation broth (inoculum);
• (d) feeding at least a part of the aqueous phase obtained in said step (b) and, optionally, the second fermentation broth (inoculum) obtained in said step (c) and/or at least a part of said lignocellulosic hydrolyzate, to a third fermentation device in the presence of at least one microorganism capable of using both sugars with five carbon atoms (C5) and sugars with six carbon atoms (C6), obtaining a third fermentation broth;
• (e) subjecting said third fermentation broth to separation obtaining bioethanol.