Document Abstract
In this study, a simple spectrophotometric method has been applied
to investigate the adsorption of Hg(II) from aqueous solution on
glycine functionalised magnetic nanoparticles entrapped calcium
alginate beads (GFMNPECABs) from aqueous solution. The adsorbent
was characterised by Fourier Transform Infrared (FT-IR) spectroscopy,
Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD)
and Brunauer-Emmett-Teller (BET) analysis. The influence of pH,
contact time, temperature, adsorbent dose etc. were studied and
optimised. The results of batch adsorption experiment showed that
maximum adsorption capacity of 3.59 mg g‒1 was obtained at pH 5
and 65 minutes of contact time.The adsorption behaviour of Hg(II)
was evaluated using Langmuir, Freundlich and Temkin isotherm and
it was found that the data best fitted with the Freundlich model. The
kinetic study revealed that the adsorption follows pseudo-secondorder
kinetics with a high correlation coefficient of R2 = 0.9998. The
thermodynamic investigation verified the endothermic and spontaneous
nature of the adsorption process with an enthalpy change
(ΔH) and entropy change (ΔS) of 20.25 kJ mol−1 and 79.88 J mol‒1 K,
respectively. The adsorption studies were monitored based on the
reaction of Hg(II) with iodine and leucocrystal violet. This study
shows that GFMNPECABs is a promising adsorbent for removal of
Hg(II) from aqueous solution and the above spectrophotometric
method could be satisfactorily applied for adsorption studies.