Chapter 3
Adsorption of Pb(II), Cu(II), Ni(II),
Zn(II), Cr(VI) and Cd(II) Ions
by Microwave-Improved Grafting
Technique of Cross-Linking Composite
Chitosan Beads. Studies Concerning
Equilibrium, Isotherm and Desorption
Abstract Due to the flexibility of chitosan, chemical improvement of chitosan has
become progressively important, allowing the material to be easily changed in a way
that enhances its characteristics in binding processes. Chitosan solution was crosslinked with glutaraldehyde in this study, and the cross-linked solution was used
in the manufacture of the beads and then grafted with ethylene acrylic acid afterwards. Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), X-ray diffraction (XRD) and thermogravimetric analysis (TGA) were
used to obtain the chemical properties of the beads. Binding of Pb(II), Cu(II), Ni(II),
Zn(II), Cr(II) and Cd(II) ions from aqueous solution by grafted cross-linking chitosan
beads (GXXB) was examined in relation to pH, temperature, initial concentration,
contact time, agitation speed and ionic strength. The results found from binding
investigation were applied in isotherm, thermodynamic and kinetic report. The model
such as Langmuir, Temkin and Dubinin–kaganer–Radushkevich (DKR) was effective in explaining the isotherm data for the binding of adsorbate onto adsorbent,
while the model Freundlich was not productive in explaining the experimental data.
Pseudo-second-order and intraparticle model were accurate in explaining kinetic
data. Thermodynamic parameters including Gibb free energy shift (G
o ), enthalpy
change (H
o ) and entropy change (S
o ) were measured and the marks reported a spontaneous and endothermic binding of Pb(II), Cu(II), Ni(II), Zn(II), Cr(II) and Cd(II)
ions on GXXB. For the adsorbate examined, the regeneration of the spent GXXB
was successful.
3.1 Introduction
Large amounts of adsorbates including Pb(II), Cu(II), Ni(II), Zn(II), Cr(II) and Cd(II)
ions and others reach our food chain each year via wastewater discharges into water
supplies, especially in developing countries [1]. The main basis of these adsorbates is
the ever-rising chemical, electroplating, leather, tannery, galvanizing, mining, pharmaceutical, pigment and colouring industries [2–4]. That results in the application of
these metal ions globally. Heavy metal ions are unbiodegradable and poisonous pollutants that are harmful to human, animal, aquatic and general environment. In the past,
© The Author(s), under exclusive license to Springer Nature Switzerland AG 2021
E. Igberase et al., Enhanced Chitosan Material for Water Treatment,
Engineering Materials, https://doi.org/10.1007/978-3-030-71722-3_3
47
Adsorption of Pb(II), Cu(II), Ni(II),
Zn(II), Cr(VI) and Cd(II) Ions
by Microwave-Improved Grafting
Technique of Cross-Linking Composite
Chitosan Beads. Studies Concerning
Equilibrium, Isotherm and Desorption
Abstract Due to the flexibility of chitosan, chemical improvement of chitosan has
become progressively important, allowing the material to be easily changed in a way
that enhances its characteristics in binding processes. Chitosan solution was crosslinked with glutaraldehyde in this study, and the cross-linked solution was used
in the manufacture of the beads and then grafted with ethylene acrylic acid afterwards. Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), X-ray diffraction (XRD) and thermogravimetric analysis (TGA) were
used to obtain the chemical properties of the beads. Binding of Pb(II), Cu(II), Ni(II),
Zn(II), Cr(II) and Cd(II) ions from aqueous solution by grafted cross-linking chitosan
beads (GXXB) was examined in relation to pH, temperature, initial concentration,
contact time, agitation speed and ionic strength. The results found from binding
investigation were applied in isotherm, thermodynamic and kinetic report. The model
such as Langmuir, Temkin and Dubinin–kaganer–Radushkevich (DKR) was effective in explaining the isotherm data for the binding of adsorbate onto adsorbent,
while the model Freundlich was not productive in explaining the experimental data.
Pseudo-second-order and intraparticle model were accurate in explaining kinetic
data. Thermodynamic parameters including Gibb free energy shift (G
o ), enthalpy
change (H
o ) and entropy change (S
o ) were measured and the marks reported a spontaneous and endothermic binding of Pb(II), Cu(II), Ni(II), Zn(II), Cr(II) and Cd(II)
ions on GXXB. For the adsorbate examined, the regeneration of the spent GXXB
was successful.
3.1 Introduction
Large amounts of adsorbates including Pb(II), Cu(II), Ni(II), Zn(II), Cr(II) and Cd(II)
ions and others reach our food chain each year via wastewater discharges into water
supplies, especially in developing countries [1]. The main basis of these adsorbates is
the ever-rising chemical, electroplating, leather, tannery, galvanizing, mining, pharmaceutical, pigment and colouring industries [2–4]. That results in the application of
these metal ions globally. Heavy metal ions are unbiodegradable and poisonous pollutants that are harmful to human, animal, aquatic and general environment. In the past,
© The Author(s), under exclusive license to Springer Nature Switzerland AG 2021
E. Igberase et al., Enhanced Chitosan Material for Water Treatment,
Engineering Materials, https://doi.org/10.1007/978-3-030-71722-3_3
47