TITLE:
Silica Gel Supported Hydrophobic Ionic Liquid for Selective Extraction and Determination of Coumarin
AUTHORS:
Hadi M. Marwani, Esraa M. Bakhsh
KEYWORDS:
Coumarin; Silica Gel; Uptake Capacity; Ionic Liquid; Batch Method
JOURNAL NAME:
American Journal of Analytical Chemistry,
Vol.4 No.1,
January
9,
2013
ABSTRACT: In this study, a modified silica gel surface with a
hydrophobic ionic liquid (SG-1,10-PhenanNTf2) was used as an adsorbent
for a selective extraction of coumarin prior to its determination by use of
high performance liquid chromatography. Results demonstrated that
SG-1,10-PhenanNTf2 phase had a good adsorption capacity up to 85.29
mg?g?1, high selectivity, good site accessibility and fast binding
kinetics toward coumarin. The adsorption capacity for coumarin was improved by
62.33% with the SG-1,10-PhenanNTf2 phase as compared to activated silica
gel. Adsorption isotherm data displayed that the adsorption process was mainly
monolayer on a homogeneous adsorbent surface, confirming the validity
of Langmuir adsorption isotherm model. The adsorption of coumarin on the
SG-1,10-PhenanNTf2 phase was accomplished after
only 60 min contact time. Results of kinetic models showed that the adsorption
of coumarin on the SG-1,10-PhenanNTf2 phase obeyed a pseudo
second-order kinetic model. Finally, the efficiency of this methodology was
confirmed by applying it to real water samples.