Equilibrium studies and
kinetics mechanism for the removal of basic and reactive
dyes in both single and binary systems using EDTA modified
Siew-Teng Ong1*, Weng-Nam Lee2, Pei-Sin
Keng3, Siew-Ling Lee4, Yung-Tse Hung5
and Sie-Tiong Ha1
of Chemical Science, Faculty of Science, Universiti Tunku
Universiti, Bandar Barat, 31900 Kampar, Perak, Malaysia.
of Science, Faculty of Engineering and Science, Universiti
Tunku Abdul Rahman, Jalan Genting Kelang, Setapak 53300
Kuala Lumpur, Malaysia.
Department of Pharmaceutical Chemistry, International
No.126, Jalan 19/155B, Bukit Jalil, 57000 Kuala Lumpur,
Sina Institute for Fundamental Science Studies, Universiti
Teknologi Malaysia, 81310 Skudai, Johor Malaysia.
of Civil and Environmental Engineering, Cleveland State
University, Cleveland, Ohio, USA.
*Corresponding author. E-mail:
25 February, 2010
potential of using ethylenediamine tetraacetic acid modified
rice husk (ERH) to remove different types of dyes, namely
basic and reactive dyes were studied. Sorption
characteristic of ERH showed that it was pH dependent. The
kinetics of sorption for both dyes was rapid within the
first 60 min regardless of its initial concentration. Using
the pseudo-second order kinetics model, the predicted
uptakes of Methylene Blue (MB) and Reactive Orange 16 (RO16)
agreed closely with experimental values obtained. Three
isotherm models were used to fit with equilibrium data,
namely Langmuir, Freundlich and BET models. It was found
that the equilibrium fitted well in Freundlich isotherm with
higher regression coefficient value, R2.
Thermodynamic parameters showed that the sorption of process
of MB and RO16 are exothermic and endothermic, respectively.
Decrease in sorbent particle size led to an increase in the
sorption of dyes. The study revealed that ERH is suitable to
use as a single sorbent to remove both MB and RO16 in all
modified rice husk, adsorption, binary mixture system,
methylene blue, reactive orange 16.