Chapter 5
Biopolymer Chitosan Membranes
Prepared from Fishery Waste
for the Removal of Zinc Ions
from Aqueous Systems by Adsorption
Abstract Chitosan was derived from the Cape rock crab outer shell, as seen
in the areas of Cape Town, South Africa, and was exploited in the manufacture chitosan particles employed in the development of porous polymer chitosan
membranes through a step reversal procedure. The chitosan membrane was crosslinked with 2.5% glutaraldehyde; chitosan membrane (CS) and cross-linked chitosan
membrane (XCS) were characterize by FTIR, XRD, SEM-EDX and TGA. Equilibrium findings showed that the Langmuir equilibrium model can be appropriately
applied in explaining zinc adsorption on XCS and the maximum adsorption potential for temperatures between 303 and 313 K was 2.64 mmol g
−1 . The adsorption
operation was discovered to be endothermic, with 20 kJ mol
−1 adsorption enthalpy.
Flux via XCS is a mechanical mechanism with a decline in the adsorption rate (1.91–
1.30 mmol g
−1 ) as the flux rises (2–55 L m
−2 hr
−1 ). XCS adsorption of metal ions
has also been noticed to be impacted by co-ions, where the influence of nitrates has
been considered to restrict adsorption, whereas sulphates have been proven to raise
adsorption. The regeneration of the adsorbed zinc ions was accomplished employing
sulphuric acid and hydrochloric acid solutions as eluants. The former was considered
to be a more powerful eluant. As a result, a sulphuric acid solution with a pH of 2 can
retrieve up to 90% of the adsorbed zinc. Consequently, upon recovery, the adsorption
capacity was observed to be lowered. Upon regeneration, this decline in adsorption
efficiency may be due to membrane mass loss of approximately 11%. The functional
stability of the membrane was compromised following two regeneration periods, and
the membranes were no longer functional.
5.1 Introduction
Separated from aquatic life, polymeric composite materials are relatively economical
and ecologically convenient solid adsorbents that show significant affinity against
metal ions. Numerous authors have documented findings in which chitosan biopolymers bind with metal ions to produce chitosan–metal complexes, usually to extract
heavy metals from polluted waters [1–3]. Polysaccharide biopolymers, derived
from aquatic organisms, are potentially inexpensive and environmentally sustainable
© 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_5
93
Biopolymer Chitosan Membranes
Prepared from Fishery Waste
for the Removal of Zinc Ions
from Aqueous Systems by Adsorption
Abstract Chitosan was derived from the Cape rock crab outer shell, as seen
in the areas of Cape Town, South Africa, and was exploited in the manufacture chitosan particles employed in the development of porous polymer chitosan
membranes through a step reversal procedure. The chitosan membrane was crosslinked with 2.5% glutaraldehyde; chitosan membrane (CS) and cross-linked chitosan
membrane (XCS) were characterize by FTIR, XRD, SEM-EDX and TGA. Equilibrium findings showed that the Langmuir equilibrium model can be appropriately
applied in explaining zinc adsorption on XCS and the maximum adsorption potential for temperatures between 303 and 313 K was 2.64 mmol g
−1 . The adsorption
operation was discovered to be endothermic, with 20 kJ mol
−1 adsorption enthalpy.
Flux via XCS is a mechanical mechanism with a decline in the adsorption rate (1.91–
1.30 mmol g
−1 ) as the flux rises (2–55 L m
−2 hr
−1 ). XCS adsorption of metal ions
has also been noticed to be impacted by co-ions, where the influence of nitrates has
been considered to restrict adsorption, whereas sulphates have been proven to raise
adsorption. The regeneration of the adsorbed zinc ions was accomplished employing
sulphuric acid and hydrochloric acid solutions as eluants. The former was considered
to be a more powerful eluant. As a result, a sulphuric acid solution with a pH of 2 can
retrieve up to 90% of the adsorbed zinc. Consequently, upon recovery, the adsorption
capacity was observed to be lowered. Upon regeneration, this decline in adsorption
efficiency may be due to membrane mass loss of approximately 11%. The functional
stability of the membrane was compromised following two regeneration periods, and
the membranes were no longer functional.
5.1 Introduction
Separated from aquatic life, polymeric composite materials are relatively economical
and ecologically convenient solid adsorbents that show significant affinity against
metal ions. Numerous authors have documented findings in which chitosan biopolymers bind with metal ions to produce chitosan–metal complexes, usually to extract
heavy metals from polluted waters [1–3]. Polysaccharide biopolymers, derived
from aquatic organisms, are potentially inexpensive and environmentally sustainable
© 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_5
93