title: Continuous flow adsorption of methylene blue by cellulose nanocrystal-alginate hydrogel beads in fixed bed columns.
abstract: The adsorption behavior of methylene blue by cellulose nanocrystal-alginate (CNC-ALG) hydrogel beads in a fixed bed column was studied by varying the initial dye concentrations, bed depths and flow rates. An unusual phenomenon was observed in the early phase of the adsorption, and the phenomenon was elucidated by varying other critical design parameters, such as the flow direction, diameter of column and composition of adsorbent. The swelling and shrinkage of hydrogel beads during the adsorption was responsible for the anomalous concentration versus time profile of the adsorption process. The maximum adsorption capacity of the column was 255.5mg/g, which is in agreement with the batch study determined from the Langmuir adsorption isotherm. A comprehensive understanding on the adsorption mechanism of CNC-ALG hydrogel beads during the early stages of adsorption was derived from this study.
authors.affiliation: Department of Chemical Engineering, Waterloo Institute for Nanotechnology, University of Waterloo, 200 University Avenue West, Waterloo, ON, Canada N2L 3G1.
authors.forename: Nishil
authors.initials: N
authors.lastname: Mohammed
authors.affiliation: Department of Chemical Engineering, Waterloo Institute for Nanotechnology, University of Waterloo, 200 University Avenue West, Waterloo, ON, Canada N2L 3G1.
authors.forename: Nathan
authors.initials: N
authors.lastname: Grishkewich
authors.affiliation: Department of Chemical Engineering, Waterloo Institute for Nanotechnology, University of Waterloo, 200 University Avenue West, Waterloo, ON, Canada N2L 3G1.
authors.forename: Herman Ambrose
authors.initials: HA
authors.lastname: Waeijen
authors.affiliation: CelluForce Inc., 625, Président-Kennedy Avenue, Montreal, QC, Canada H3A 1K2.
authors.forename: Richard M
authors.initials: RM
authors.lastname: Berry
authors.affiliation: Department of Chemical Engineering, Waterloo Institute for Nanotechnology, University of Waterloo, 200 University Avenue West, Waterloo, ON, Canada N2L 3G1. Electronic address: mkctam@uwaterloo.ca.
authors.forename: Kam Chiu
authors.initials: KC
authors.lastname: Tam
keywords: Adsorption; Alginate; Cellulose nanocrystals; Fixed bed column; Hydrogel beads