Title:
Autohydrolysis and Acid Hydrolysis of Olive-Tree Pruning Debris. Fermentation by Debaryomyces Hansenii to obtain Ethanol and Xylitol
Author(s):
Mateo, S., Moya, A.J., Puentes, J.G., Bravo, V., Sánchez, S.
Document(s):
Paper
Abstract:
Debris from olive-tree pruning represents a great volume of residual biomass in Spain, where annual production reaches 4.0 million tonnes, from which chemical, fuel and biological products can be developed. The economic feasibility of the process involves making use of the entire debris in its three main fractions: hemicellulose, cellulose and lignin. In this study we have studied the main factors that affect to the autohydrolysis process (temperature, time and acid concentration) as well as the influence of the hydrolytic agent concentration in the acid hydrolysis of the olive-tree pruning debris. Subsequently the obtained hydrolizates were fermented by Debaryomyces hansenii (NRRL Y-7426) to produce ethanol and xylitol. The autohydrolysis experiments were performed on a batch stainless reactor and the acid hydrolysis experiments were performed using hydrochloric acid in concentrations ranging from 0.1 to 1.0 kmol/m3, a temperature of 90 ºC, and a time of 180 min. The fermentation experiments were conducted on a laboratory scale in a batch-culture bioreactor at pH 4.5 and 30 ºC. We have verified that the better conditions for time, temperature and acid concentration during the autohydrolysis process were 0 min, 200ºC and 0.025 kmol/m3 of sulphuric acid respectively (severity factor, log Ro = 3.4). On the other hand, we have assayed the hydrolysis of all the autohydrolysis matter and just the solid residue, concluding that it is more interesting to carry out all the starting material because of the greater monosaccharides yields.
Keywords:
ethanol, fermentation, autohydrolysis, acid hydrolysis, olive-tree pruning, Debaryomyces hansenii, xylitol
Topic:
Industrial demonstration and market implementation
Subtopic:
Biorefineries and industrial materials
Event:
18th European Biomass Conference and Exhibition
Session:
VP4.4.8
Pages:
1994 - 1997
ISBN-13:
978-88-89407-56-1
ISBN-10:
88-89407-56-5
Paper DOI:
10.5071/18thEUBCE2010-VP4.4.8
Price:
FREE
