TITLE:
Adsorptive Removal of Phosphate from Aqueous Solution by Magnetic-Supported Kaolinite: Characteristics, Isotherm and Kinetic Studies
AUTHORS:
Adebola Abosede Adeyi, Toluwalope Gbemileke Abayomi, Mihir Kumar Purkait, Piyal Mondal
KEYWORDS:
Magnetite, Kaolin, Phosphate, Adsorption
JOURNAL NAME:
Open Journal of Applied Sciences,
Vol.9 No.7,
July
18,
2019
ABSTRACT: Natural kaolin (NK) and magnetite-modified kaolin (MK) prepared by co-precipitation
were used as adsorbents to remove phosphate from aqueous solution. The
materials were characterized using X-ray diffractometer (XRD), Fourier transform infrared spectroscopy (FTIR),
field-emission scanning electron microscope (FESEM), and vibrating
sample magnetometer (VSM). Batch adsorption experiment was carried out to
determine the phosphate removal efficiencies of these materials. The
magnetic-supported kaolin showed better dispersion and less co-aggregation
which ensured better fusion of the kaolin with magnetite (Fe3O4).
The removal process of phosphate was governed by physico-chemical process. The
results demonstrated that the adsorption of phosphate onto NK and MK was highly
pH-dependent and the kinetics of the adsorption followed pseudo-second order
equation. The adsorption data of Mk adsorbent fitted better with the Freundlich
isotherm equation. The MK showed much better adsorption capacity per mass of MK
(52.91 mg/g) than untreated NK (17.61 mg/g). Since the magnetic kaolin can be
easily prepared, it enables promising application for the removal of phosphate
from aqueous solution. Hence, this new class of efficient adsorbent (MK), can
have a variety of application in industrial processes.