Valorization of Eucalyptus nitens bark by organosolv pretreatment for the production of advanced biofuels

Abstract

The biofuels production from alternative and renewable raw materials is mandatory to achieve sustainable growth based on a bioeconomy. Eucalyptus bark is a waste generated during the chemical manufacturing of Eucalyptus pulp that can be used as an alternative source of biomass, suitable for the production of biofuels. In this work, Eucalyptus nitens bark (ENB) was fractionated by organosolv treatment for ethanol production. For that, a Doehlert experimental design was carried out to evaluate the dependent variables: temperature (170-200°C), time (30-90 min) and ethanol-water percentage (50-80 %) on delignification of Eucalyptus bark. Organosolv process was suitable for the fractionation of E. nitens bark. After treatment, 74-93 % of glucan was recovered and 25-52 % of delignification was achieved. Delignified ENB was subjected to simultaneous saccharification and fermentation process for bioethanol production. The results showed that the variables temperature and time of organosolv process had significant influence on ethanol production. The organosolv pretreatment improved the ethanol yield from 32 to 99%. This work shows a suitable process for the valorization of Eucalyptus bark into bioethanol.

Co-production of biofuels and value-added compounds from industrial Eucalyptus globulus bark residues using hydrothermal treatment

“…As for eucalyptus wood, eucalyptus bark also presents an interesting potential, mostly due to a considerable amount of polysaccharides (67.17%) and, to a lower extent, lignin (21.86% Klason lignin) and a minimal content of ash (2.63%), as shown in Table 1. Indeed, cellulose and xylan accounts alone for nearly 63% of EBR total composition (Table 1), rendering an interesting potential for the production of both chemicals and energy [22,40]. This composition can be compared with previous characterizations of barks from several species of Eucalyptus, such as E. globulus and E. nitens [16,22,41].…”

“…On the other hand, the valorization of eucalyptus barks for bioethanol production has barely been studied with very few works conducted so far. The organosolv delignification of E. nitens bark allowed the production of 33 g/L of ethanol [22]. On the other hand, 0.14 g/g bark of ethanol was obtained from Eucalyptus dunnii bark after an ionic liquid pretreatment [23].…”

Multi-Step Exploitation of Raw Arundo donax L. for the Selective Synthesis of Second-Generation Sugars by Chemical and Biological Route

“…They aimed at improving the efficiency of the hydrolysis of the polysaccharides [11][12][13] to release second-generation sugars (xylose and glucose), furfural, 5-hydroxymethylfurfural (HMF), levulinic acid (LA) and formic acid (FA) [14][15][16][17][18][19][20][21]. A large number of pretreatments were reported in the literature employing mineral acids [22][23][24], inorganic salts [25,26], alkaline solutions [23,27], ionic liquids [28,29], and organosolv [30,31], in addition to physico-chemical techniques, such as steam explosion [32]. The choice of suitable pretreatment strongly depends on the biomass fraction that should be exploited and on the target products.…”

Biorefining Oat Husks into High-Quality Lignin and Enzymatically Digestible Cellulose with Acid-Catalyzed Ethanol Organosolv Pretreatment

“…Exceptions include the works carried out by Matsakas et al [36] using silver birch wood chips, by Patel et al [37] using Norway spruce, and by Yuan et al [38] using corn stover, wherein an S/L ratio of 1:2 was used. Research works in the literature reported lignin-rich fractions containing >90% lignin [8] achieved via different organosolv pretreatment strategies, namely HCl-catalyzed tetrahydro-2-furanmethanol pretreatment of eucalyptus [39], auto-catalyzed ethanol pretreatment of Eucalyptus nitens bark [40], and oxalic acid-catalyzed glycerol pretreatment of sugarcane trash [41]. The research on organosolv pretreatment has been very heterogeneous regarding the range of systems and substrates used, making in-depth knowledge difficult to achieve due to the wide range of results achieved.…”