Sunday, May 4, 2008
3-53

Olive tree biomass as a raw material for ethanol production. Comparison of pretreatments

Cristóbal Cara1, Encarnación Ruiz1, Inmaculada Romero1, Manuel Moya1, María José Negro2, Jose M. Oliva2, Paloma Manzanares2, and Eulogio Castro1. (1) Chemical, Environmental and Materials Engineering, University of Jaen, Campus Las Lagunillas, Jaen, 23071, Spain, (2) Renewable Energies Department, CIEMAT, Avda. Complutense 22, Madrid, Spain

Olive tree biomass obtained by pruning constitutes one of the main agricultural residues in Mediterranean countries. Olive tree culture practices include pruning, an essential annual operation that eliminates unproductive branches and prepares trees for the next crop. Pruning generates a huge amount of a cheap, renewable lignocellulosic residue, lacking of alternative uses, which must be eliminated to prevent propagation of vegetal diseases. To date, pruning residues are either burnt or grindered and scattered in fields, causing environmental concerns and disposal costs. The use of olive tree biomass as a raw material for fuel ethanol production has been proposed.

 Ethanol production from lignocellulose residues requires, as a first step, a residue pretreatment. In this work, several pretreatment methods including steam explosion (with or without water or acid preimpregnation), liquid hot water, and dilute acid prehydrolysis are compared on olive tree pruning biomass. The pretreatment performance was evaluated based on both the improvement in cellulose digestibility (pretreated solid residue) and the hemicellulose sugar recovery (liquid fractions).

 Results show that the highest ethanol yields from the cellulose residue are obtained when applying hydrothermal pretreatments, but the hemicelluosic sugar recoveries are quite low. On the other hand, dilute acid pretreatment produced higher sugar yields taking into account both glucose from enzymatic hydrolysis of the pretreated solid and soluble and hemicellulose derived sugars in the liquid fractions issued from pretreatment.


See more of Poster Session One
See more of General Submissions

See more of The 30th Symposium on Biotechnology for Fuels and Chemicals (May 4 -- 7, 2008)