title: Rate studies on the adsorption of some dyestuffs and p-nitrophenol by chitosan and monocarboxymethylated(mcm)-chitosan from aqueous solution.
abstract: In this study, the effect of temperature on the adsorption of some dyestuffs [orange II (O-II), crystal violet (CV) and reactive blue 5 (RB5)] and p-nitrophenol (PNP) by chitosan and of O-II and CV by modified chitosan [monocarboxymethylated(mcm)-chitosan] from aqueous solution was investigated. Kinetical data related to the adsorptions of each dyestuff and PNP by chitosan and of O-II and CV by mcm-chitosan were applied to Lagergren and Weber-Morris equations, and adsorption rate constants (kads) and pore diffusion rate constants (kp) were determined, respectively. In addition, Langmuir isotherm constants with experimental data related to the adsorptions of O-II and CV by chitosan and of CV by mcm-chitosan were applied to McKay et al. equation, and external mass transfer coefficients (kf) were also determined. Lastly, chitosan and mcm-chitosan were compared according to their dyestuffs and PNP uptake capabilities. It was seen that mcm-chitosan removed more O-II (99.2%) and RB5 (34.9%) but less CV (3.1%) and PNP (0.9%).
authors.affiliation: Department of Chemistry, Faculty of Education, Dicle University, 21280 Diyarbakir, Turkey. iuzun21@yahoo.com
authors.forename: Ilhan
authors.initials: I
authors.lastname: Uzun
authors.forename: Fuat
authors.initials: F
authors.lastname: Güzel
mesh_terms: D000327:Adsorption; D048271:Chitosan / Q000737:chemistry; D004058:Diffusion; D007700:Kinetics; D009596:Nitrophenols / Q000737:chemistry / Q000302:isolation & purification*; D013696:Temperature; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*; D018508:Water Purification / Q000379:methods
chemical_list: D009596:Nitrophenols; D014874:Water Pollutants, Chemical; D048271:Chitosan; C024836:4-nitrophenol