2024-03-28T21:14:17Zhttp://uvadoc.uva.es/oai/requestoai:uvadoc.uva.es:10324/284422021-06-24T07:44:41Zcom_10324_31661com_10324_952com_10324_894com_10324_1173com_10324_931col_10324_31662col_10324_1371
Pressure and temperature effect on cellulose hydrolysis in pressurized water
Cantero Sposetti, Danilo Alberto
Sánchez Tapia, Ángel
Bermejo Roda, Maria Dolores
Cocero Alonso, María José
In this study, the effect of temperature and pressure on cellulose and glucose hydrolysis in a hydrothermal media was analyzed. To do so, cellulose hydrolysis experiments were carried out in a continuous pilot plant capable of operating up to 400 °C and 27 MPa. The reaction times were varied between 0.004 and 40 s. The main products of cellulose hydrolysis were oligosaccharides, cellobiose, glucose and fructose. The concentration profiles of each component followed a similar behavior at a fixed temperature changing pressure. Nevertheless, glucose and fructose hydrolysis reaction to give dehydration of retro aldol condensation products were strongly affected by pressure and temperature. When increasing temperature in the studied range, the reaction of glucose isomerization to fructose and the production of 5-hydroxymethylfurfural (5-HMF) obtained through fructose dehydration were inhibited. On the other hand, 5-HMF production was favored by high proton concentrations due to water dissociation. Thus, at a constant temperature, the production of 5-HMF was increased by rising the ionic product of water (increasing pressure). The production of glycolaldehyde (retro-aldol condensation of glucose) was increased by rising temperature and pressure. The kinetic constants of the cellulose hydrolysis reactions were determined at the experimented conditions using the experimental results. The kinetic constants were plotted against temperature and pressure to determine the activation energy and the activation volume for each reaction, respectively. Pressure seems to have no effect on the cellulose hydrolysis kinetic to simple sugars. However, at supercritical water temperatures the increment in pressure disfavored the glucose isomerization and dehydration reactions.
2018-01-28T18:59:06Z
2018-01-28T18:59:06Z
2018-01-28T18:59:06Z
2015
info:eu-repo/semantics/article
Chemical Engineering Journal, 2015, Volume 276, pp.145-154
1385-8947
http://uvadoc.uva.es/handle/10324/28442
10.1016/j.cej.2015.04.076
eng
https://www.sciencedirect.com/science/article/pii/S1385894715005665
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-nd/4.0/
Attribution-NonCommercial-NoDerivatives 4.0 International
Elsevier