RT info:eu-repo/semantics/article
T1 Redefining conventional biomass hydrolysis models by including mass transfer effects. Kinetic model of cellulose hydrolysis in supercritical water
A1 Vaquerizo Martín, Luis
A1 Abad Fernández, Nerea
A1 Mato Chaín, Rafael Bartolomé
A1 Cocero Alonso, María José
K1 Mass transfer
K1 Shrinking Core Model
K1 particle surface
K1 oligosaccharides layer
K1 covering conversion
AB Conventional kinetic models of cellulose hydrolysis in supercritical water do not accurately represent the operation with concentrated suspensions since they neglect the mass transfer effects. This work proposes a kinetic model which is able to reproduce cellulose hydrolysis at high concentrations providing the opt imum reaction conditions to obtain nanocellulose particles and oligomers of controlled size. The basic idea of the model, which is applicable to other lignocellulosic materials, is that the hydrolysis of the cellulose particles generates an oligosaccharides layer which creates a mass transfer resistance. Therefore, it considers both the diffusion of the water molecules from the bulk phase to the surfaces of the cellulose particles and the superficial hydrolysis kinetics. Experimental points were obtained working with two different cellulose types (Dp=75 μm and Dp=50 μm) at 390 °C and 25 MPa, residence times between 50 ms and 250 ms and initial cellulose suspension concentration from 3% to 7% w/w (1% to 2.3% w/w at the inlet of the reactor). The average deviation between the experimental points and the theoretical values is lower than 10% proving the applicability of the kinetic model. The experimental and theoretical results demonstrated that increasing the  total number of cellulose particles, either increasing the initial concentration or decreasing the  average particle diameter, reduces the hydrolysis rate.
PB Elsevier
SN 1385-8947
YR 2018
FD 2018
LK http://uvadoc.uva.es/handle/10324/31390
UL http://uvadoc.uva.es/handle/10324/31390
LA eng
NO Chemical Engineering Journal 350, 2018, 463-473
NO Producción Científica
DS UVaDOC
RD 12-nov-2024