Conference article

Improvement of Enzymatic Hydrolysis of Rice Straw by N-Methylmorpholine-N-Oxide (NMMO) Pretreatment

Nafiseh Poornejad
Department of Chemical Engineering, Isfahan University of Technology, Isfahan, Iran

S. M. Amin Salehi
Department of Chemical Engineering, Isfahan University of Technology, Isfahan, Iran

Keikhosro Karimi
Department of Chemical Engineering, Isfahan University of Technology, Isfahan, Iran

M. J. Taherzadeh
School of Engineering, University of Borås, Borås, Sweden

Tayebeh Behzad
Department of Chemical Engineering, Isfahan University of Technology, Isfahan, Iran

Download articlehttp://dx.doi.org/10.3384/ecp11057566

Published in: World Renewable Energy Congress - Sweden; 8-13 May; 2011; Linköping; Sweden

Linköping Electronic Conference Proceedings 57:76, p. 566-570

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Published: 2011-11-03

ISBN: 978-91-7393-070-3

ISSN: 1650-3686 (print), 1650-3740 (online)

Abstract

“Food versus energy” analysis resulted in demanding raw materials which don’t have conflict with food industries. The lignocellulosic materials are the most interested option; since not only these materials don’t have conflict with food industries; but also there several economical and environmental advantages in those substrates for bioethanol production.

However; the lignocellulosic materials are recalcitrant to both acid and enzymatic hydrolysis. As a result; some pretreatment steps must be taken before hydrolysis. One of the most effective pretreatment methods is treatment with cellulosic solvent.

In this work rice straw; an agricultural residue which is mainly unused was pretreated with an industrial solvent; N-methylmorpholine-N-oxide (NMMO). The pretreatments were performed at 120°C for 1; 3;5 hours with 85% NMMO solution. The treated materials were then subjected to enzymatic hydrolysis by a mixture of commercial cellulase and glucosidase.

The results showed significant improvement on the enzymatic hydrolysis. Almost complete hydrolysis of the cellulose in the straw was observed after 5 h treatment with NMMO at ambient pressure and 120°C.

Keywords

Pretreatment; NMMO; rice straw; enzymatic hydrolysis

References

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