Supercritical water hydrolysis: a green pathway for producing low-molecular-weight cellulose

Loading...
Thumbnail Image
Journal Title
Journal ISSN
Volume Title
A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä
This publication is imported from Aalto University research portal.
View publication in the Research portal
View/Open full text file from the Research portal
Date
2016
Major/Subject
Mcode
Degree programme
Language
en
Pages
6516-6525
Series
GREEN CHEMISTRY, Volume 18, issue 24
Abstract
This work discusses the suitability of supercritical water treatment (SCWT) for depolymerising microcrystalline cellulose in a controlled way. The SCWT partially hydrolysed cellulose down to a mixture of three valuable products: water-insoluble low-molecular-weight cellulose (WI-LMWC) precipitate, water-soluble low-molecular-weight cellulose (WS-LMWC) oligomers, and glucose. The conditions under which the energy demand for obtaining these products is minimised were identified by adjusting the reaction time inside the continuous reactor and the temperature around the critical point. The optimum conditions were 370 °C and 0.4 seconds for producing WI-LMWC and 360 °C and 0.5 seconds for producing WS-LMWC, with maximum yields of 19 wt% and 50 wt%, respectively. This work also shows that the water-insoluble product precipitates into crystalline cellulose II arrangements. This precipitation phenomenon enabled isolation of cellulose chains of different lengths according to their respective solubilities in ambient water. The results show that SCWT is a relevant process for producing narrowly distributed fractions of low-molecular-weight cellulose using water and heat only.
Description
Keywords
Other note
Citation
Buffiere , J , Ahvenainen , P , Borrega Sabate , M , Svedström , K & Sixta , H 2016 , ' Supercritical water hydrolysis: a green pathway for producing low-molecular-weight cellulose ' , Green Chemistry , vol. 18 , no. 24 , pp. 6516-6525 . https://doi.org/10.1039/C6GC02544G