Lignocellulosic biorefinery for the production of cellulose and pentoses for the production of green surface active agents – SUCROL
Lignocellulosic biorefinery for the production of cellulose and green surface active agents
Wood : a source of non food sugars for the production of bioproducts
Wood : a source of non food sugars for the production of bioproducts
The pulp and paper industry produces about 150 millions tons per year of cellulosic fibers, with a purity of 80-98% depending on the final usages, and mainly from wood resources.<br />Cellulose, which constitutes about 40% of wood, is the only wood constituent that is valorized as a product in paper pulp mills, the other wood constituants being burned to produce energy.<br />An interesting strategy would be to extract part of the hemicelluloses from wood (they constitute the second major component of wood) prior to the cellulose extraction to valorize them. They are polymers of sugars, mainly composed of xylans (polymer of xylose) or glucomannans (polymers of glucose and mannose) depending on the wood species. <br />The objective of this project if to develop the production of bio-based non ionic surface active agents from sugars extracted from wood in a cellulose production mill. Provided that the quality of the cellulose produced remains good, this would enable the cellulose producer to improve the profitability of the mill. The mixture of sugars extracted will have to be suitable for the production of surface active agents. <br />The biobased surface active agents will substitute part of the surface active agents produced from petrochemistry, with the additional advantage of using non-food resources. <br />
The objective of this study is to optimise both the extraction of sugars from hardwood chips (xylose and its oligomers) and the extraction of cellulose, to obtain a sugar flow that could be valorised into surface active agents and cellulose of good quality. Synthesis of non ionic surface active agents (here alkylpolyxylosides) from xylose and its oligomers and possibly other sugars will have to be adapted.
Two issues will have to be solved : the extraction process should maximize the sugar concentration without degrading the sugars, and without any detrimental effect on the cellulose that is remaining in the wood chips. The second issue is whether the surface active agent synthesis will be possible despite the fact that a mixture of sugars in monomeric and oligomeric form is present as well as some other wood constituents.
Results obtained during the SUCROL project have shown that it was possible to extract a significant amount of sugars from hardwood species, while enabling the production of a cellulose of good quality. Furthermore it was found that the sugar extraction from wood facilitates the process of extraction of cellulose from wood, which represents a additional advantage for the industry.
The liquors extracted from wood, containing mainly sugars in their monomeric and oligomeric forms, were used to synthetisesurface active agents, provided that the synthesis process is adapted.
The expertise gained in this project has led two of the partners to participate in a wider project financed by FUI, the Polywood project, in the frame of AXELERA.
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Results of this sudy has been presented at four international scientific conferences (European Workshop on Lignocellulosics and Pulp (Helsinki), Nordic Wood Biorefinery Conference (Helsinki), Wood Chem Conference (Nancy) et International Symposium on Lignocellulosics, Fibers and Pulp (Vancouver)), at a technical workshop organized by AXELERA. One scientific paper has been published in a peer-reviewed journal (Holzforschung) and one popularization article has been published in “Actualité Chimique”.
Summary
The French pulp industry is competing against South American (Brazilian) and Asian (Indonesian) companies which are capable of producing wood pulp at a much lower price, thanks to the availability of a cheaper raw material (eucalyptus, acacia). The definition of a new economical model is the only way to stay alive in this competition. The model which seems the most appropriate today is the paper biorefinery in which all the main wood chemical components are extracted and used in a most valuable manner. This project aims at defining an extraction process for the hemicelluloses present in hardwoods, which will take place before kraft cooking and which will give a flow of pentoses in an appropriate form for chemical purposes, without affecting the quality of the kraft cellulose.
The use of pentoses has been investigated to a much lesser extent than that of hexoses. This is due to the fact that the latter are dominant in the agro-materials used today as sugar sources. However the situation is different in hardwood trees and most of the agricultural residues (straw…) in which they may represent more than 30% in weight.
The surface active agents industry has recently developed new families of biomass based products (like the alkylpolyglycosides -APG). Their potential is very high but their development is slowed by their relatively high cost. The availability of new sources of xylose at a cheaper price will represent a real breakthrough for the development of new applications for the APG. The synthesis and properties of the xylose-based APG will be investigated.
Project coordination
Christine Chirat (INSTITUT POLYTECHNIQUE DE GRENOBLE)
The author of this summary is the project coordinator, who is responsible for the content of this summary. The ANR declines any responsibility as for its contents.
Partnership
GRENOBLE INP INSTITUT POLYTECHNIQUE DE GRENOBLE
FIBRE EXCELLENCE R&D KRAFT FIBRE EXCELLENCE R&D KRAFT
SEPPIC SOC EXPLOIT PRODUITS INDUSTR CHIMIQUES
Help of the ANR 268,922 euros
Beginning and duration of the scientific project:
- 36 Months
