Effect of Pre-Extraction on Composition of Residual Liquor Obtained from Catalytic Organosolv Pulping of Sugar Maple Bark

Abstract

Background: We have determined previously that the water extract of sugar maple bark contained an important quantity of a complex sugar. In this study, we investigated the organosolv pulping of pre-extracted bark to follow the acid conversion of sugars into major products, furfural and 5-hydroxymethyl-2-furfural (HMF), while comparing the structures of organosolv lignins. Methods: The bark particles were pre-extracted with an ethanol–water mixture or water only. The extractives-free barks were then converted into cellulosic pulp and lignin by a patented organosolv process. The composition of residual liquor was determined by using HPLC-UV. Results: The pre-extraction with water was more efficient for complex sugars recovery than with the ethanol–water system. HMF was determined to be more abundant in residual liquor than furfural after ethanol–water pre-extraction while their quantities were comparable in the residual liquor after water pre-extraction. The higher yield of HMF from ethanol–water pre-extracted bark (1.18%) than from water pre-extracted (0.69%) could be related to the efficiency of complex sugar removal during the pre-extraction step. Conclusions: The pre-extraction before pulping affected, at least in part, the composition of residual liquor in terms of HMF production. These results demonstrate how the bark can be converted into valuable products and intermediates for organic synthesis.

Monitoring transformation of two tropical lignocellulosics and their lignins after residence in Benin soils

“…This reults also confirms the results regarding the high purity of the lignins under study (low carbohydrate content) (Table 3 ). The validity of choosing the organosolv process was affirmed, given that it led to high purity lignin preparations 33 , 55 . It shoud be noted that the recovery of lignin by organosolv process steadily decreased for lignins, which had been isolated from the RCW after 6, 12 and 18 months (Table 3 ).…”

Impact of pre-extraction on xylose recovery from two lignocellulosic agro-wastes

“…Furfural was analyzed by an Agilent 1100 Series HPLC system (Agilent Technologies, Santa Clara, CA, USA) using Zorbax SB-C18 column (250 mm × 4.6 mm, 5 μm) and its detection was done by diode-array detector (DAD) at 277 nm using a standard furfural solution. Furfural was eluted with a gradient of nanopure water and acetonitrile (95:5) mixture at a flow rate of 0.7 mL/min (Kasangana et al 2020). All the experiments and analyses were conducted in duplicate.…”

“…Before the hydrolysis process, the moisture content of each sample was measured as reported by NREL standard method. The pre-extraction procedure is an integral step of the organosolv process, and it will be applied to the agrowastes residues after hydrolysis (Kasangana et al 2020).…”

“…The pre-extraction could increase the porosity of both lignocellulosic agro-wastes and thus, through better penetrability of acid solution, it could improve the dilute acid hydrolysis of xylan into xylose. Moreover, application of the pre-extraction step was also investigated to evaluate the quality of the hydrolysed material for further conversion through the organosolv process applying the same pre-extraction step with ethanol-water (1:1, v/v) (Kasangana et al 2020). In this study, the xylose and furfural yields were systematically determined under the various acid hydrolysis conditions of rice husks and wheat straw.…”

Partial Structural Characterization of Complex Polysaccharide Isolated from Sugar Maple (Acer saccharum Marsh) Bark and its Anti-Inflammatory Activity

“…The conversion of sugar maple bark residues into new valuable products was performed by a catalytic organosolv process [7]. One of the main steps of this process consists in removing the extractive components from bark using ethanolwater or water only as solvents in order to preserve the efficacy of the catalyst while avoiding its interaction with phenolic extractives and soluble polysaccharides [8,9]. Therefore, the potential of converting sugar maple bark into valuable products includes the valuing of extractive compounds removed prior to the catalytic organosolv pulping.…”