Izvorni znanstveni članak
Analysis of Modified Starch Adsorption Kinetics on Cellulose Fibers via the Modified Langmuir Adsorption Theory
N. Zakrajšek
; Pulp and Paper Institute, Bogisiceva 8, 1000 Ljubljana, Slovenia
S. Knez
; b Radeče papir d.d., Njivice 7, 1433 Radeče, Slovenia; c Faculty of Chemistry and Chemical Technology, Aškerčeva cesta 5, 1000 Ljubljana, Slovenia
D. Ravnjak
; B & B Papirnica Vevče, Papirniška pot 25, 1261 Ljubljana Dobrunje, Slovenia
J. Golob
; Faculty of Chemistry and Chemical Technology, Aškerčeva cesta 5, 1000 Ljubljana, Slovenia
Sažetak
The kinetics of starch adsorption on cellulose fibers is one of the most important criteria regarding the efficient application of papermaking additives due to the continuous nature of paper production and the concomitant need to determine optimum residence times. This study presents an analysis of the kinetics of modified starch adsorption onto cellulose fibers via the application of the modified Langmuir adsorption theory (i.e. the collision theory). A model based on this theory was used to describe the kinetics of
starch binding, and to obtain the adsorption rate constant under different process conditions, which closely correspond to the conditions commonly encountered in industrial production of paper and board. The model predictions were then correlated with the experimental data. The adsorption of modified starch was found to increase by increasing the fiber consistency, shear forces (via stirring frequency) and the refining degree of fibers. The results also demonstrate that, at least in the studied range of process variables,
the modified Langmuir adsorption theory can be applied to describe the adsorption kinetics of modified starch on cellulose fibers.
Ključne riječi
(Cationically) modified starch; fibers; adsorption; collision theory; Langmuir adsorption theory
Hrčak ID:
45407
URI
Datum izdavanja:
23.12.2009.
Posjeta: 1.094 *