No abstract

A highly productive Arundo donax L. clone (Clone AD-20) was produced at full field to give 54.6 Mg total solids biomass Ha–1. Biomass was chemically and enzymatically pretreated, recovering 13.9 Mg Ha–1 of glucose and 3.6 Mg Ha–1 of xylose, i.e., 3.5–4.5 more than yield typically obtained from corn stover or switchgrass. The subsequent fermentation of the liberated sugars to organic acids (OA) by dark fermentation generated yields of 3850 Nm3 Ha–1 of biohydrogen and 14.2 Mg Ha–1 of OAs. OAs were then used as a feed to produce polyhydroxyalkanoates (PHA), with 3-hydroxybutyrate the major monomer present (PHB > 95% PHA), from a biological process using mixed microbial culture producing 5.04 Mg Ha–1 of PHA. An initial economic analysis indicated that this multistage biorefinery approach would result in a net revenue of 10,415 € Ha–1, which is approximately 9-fold greater than that obtained by a traditional biorefinery producing bioethanol.