Optimization of Laccase/Mediator System (LMS) Stage Applied in Fractionation of Eucalyptus globulus

Abstract

In a biorefinery framework, a laccase/mediator system treatment following autohydrolysis was carried out for eucalyptus wood prior to soda-anthraquinone pulping. The enzymatic and autohydrolysis conditions, with a view to maximizing the extraction of hemicelluloses while preserving the integrity of glucan, were optimized. Secondly, pulping of solid phase from Eucalyptus globulus wood autohydrolysis and the enzymatic process was carried out and compared with a conventional soda-anthraquinone (AQ) pulping process. The prehydrolysis and enzymatic delignification of the raw material prior to the delignification with soda- Anthraquinone (AQ) results in paper sheets with a lower kappa number and brightness and strength properties close to conventional soda-AQ paper and a liquid fraction rich in hemicellulose compounds that can be used in additional ways. The advantage of this biorefinery scheme is that it requires a lower concentration of chemical reagents, and lower operating times and temperature in the alkaline delignification stage, which represents an economic and environmental improvement over the conventional process.

Aprovechamiento integral de Eucalyptus globulus en un esquema de biorrefinería en doble etapa

“…El reactor se programa a una temperatura fija de 143 °C y un tiempo de reacción de 65 minutos para todos los puntos del diseño experimental de la deslignificación enzimática. La selección de las condiciones de operación se ha basado en unos ensayos previos consistentes en deslignificaciones con etanol (Garrote et al 2003) y con sosa tras un tratamiento enzimático (Loaiza et al 2019).…”

Characterization and usage of tule (Typha domingensis Pers) to obtain cellulose pulp in a biorefinery framework

“…Destroying lignocellulosic material by hydrolysis or autohydrolysis has an additional environmental advantage: it facilitates subsequent delignification and avoids the need to use sulphur compounds for this purpose. Treating the hydrolysed raw material with an alkaline reagent, e.g., a soda-anthraquinone or ethanol-soda-anthraquinone mixture, allows cellulose pulp with a low residual lignin content, a high yield and brightness, and good strength-related properties to be obtained (Caparrós et al 2008;Alfaro et al 2009Alfaro et al , 2010García et al 2017;Loaiza et al 2019).…”