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BY-NC-ND 3.0 license Open Access Published by De Gruyter Open Access January 29, 2016

Alkali treatment of fungal pretreated wheat straw for bioethanol production

  • María García-Torreiro , Miguel Álvarez Pallín , María López-Abelairas , Thelmo A. Lu-Chau and Juan M. Lema
From the journal Bioethanol


Bioconversion of lignocellulosic materials into ethanol requires an intermediate pretreatment step for conditioning biomass. Sugar yields from wheat straw were previously improved by the addition of a mild alkali pretreatment step before bioconversion by the white-rot fungus Irpex lacteus. In this work, an alternative alkaline treatment, which significantly reduces water consumption, was implemented and optimized. Sugar recovery increased 117% with respect to the previously developed alkaline wash process at optimal process conditions (30°C, 30 minutes and 35.7% (w/w) of NaOH). In order to further reduce operational costs, a system for alkali recycling was implemented. This resulted in the treatment of 150% more wheat straw using the same amount of NaOH. Finally, enzymatic hydrolysis was optimized and resulted in a reduction of enzyme dose of 33%.


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Received: 2014-11-10
Accepted: 2015-5-4
Published Online: 2016-1-29

© 2016 María García-Torreiro et al.

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

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