116
6 Modelling of Packed Bed Column for the Adsorption …
and adsorption has been communicated to have removed metal ions from water and
wastewater. O’Connell et al. [6] reported the advantages and inconveniences of the
enumerated techniques. Of these methods, however, the adsorption technique has
attracted the greatest attention because of its effectiveness in eliminating pollutants
of any kind, high selectivity, low cost and low energy consumption [7–9]. Studies
on various types of adsorbents have been conducted in recent years to develop an
adsorption technique having the consistency of recent options in the competitive environmental market. Though various types of adsorbent for example activated carbon
[10], bran [11], zeolite 4 A [12], magnetic graphene oxide [13], wheat [14], bio-chars
[15] and silicas [16] have been applied to remove metal ions, only a small number is
commercialize because of the high cost of the materials adsorbents. Chitosan adsorbent is a low-cost bio-polymer waste product mainly derived from crustaceans; it is
a partly deacetylated polymer purchased from chitin, high in protein, carotene and
calcium [17] carbonate. The presence of functional amines (–NH 2 ) and hydroxyl
group (–OH) in the backbone of chitosan gave it a distinctive character and quality.
Chitosan possesses structural and surface properties capable for the elimination of
aqueous metal ions from solutions and that is why it has been widely studied as
an adsorbent. Osifo et al. [18] comprehensively dealt with copper adsorption in a
packed bed of chitosan beads, where the adsorption capacity was determined to
be 3.8 mmol/g, while the shrinking core particle model was used to describe the
breakthrough curve for copper adsorption onto chitosan beads fairly well.
In this study, physical and chemical functionalization was introduced to enhance
the adsorption of metals properties of chitosan beads. Physical modification includes
the transformation of chitosan powder to beads for easy handling and better spreading
to binding sites [19]. On the other hand, chemical functionalization includes crosslinking of the beads to ensure stability in acid solution and practical grafting of functional groups to establish more active sites and increase the adsorption properties of
chitosan. To create chitosan beads in an industrial environment, column investigation
is extremely significant, and the majority of chitosan bead investigations reported
in the literature are also more of batch system with very minimal documentation
on metal regeneration; therefore, this study is very necessary. It has been reported
that knowledge obtained from the batch process cannot be used to remedy column
processes where the time of contact between adsorbate and adsorbent is not sufficient
for equilibrium to be established [20]. Batch procedures are often primarily limited
to remedying small quantities of contaminants. The use of packaged column systems
for large-scale wastewater remediation typically allows large amounts of contaminated water to be handled in a short period of time, and these devices can be scaled
up from the laboratory to a pilot plant project where the entire process can be easily
monitored [17]. However, the difference in concentration existing in the packed bed
column provides the driving force for the adsorption of metal ions, which results in
a satisfactory consistency of the contaminated water, and this process has been used
well by authors like [21, 22]. Several mathematical models have been developed and
applied to explain the packed bed column’s kinetic behaviour and also to predict
the breakthrough curve [2, 18]. The present study suggests a model of packed bed
column adsorption to estimate the breakthrough curve for adsorption of Cu(II) ions
6 Modelling of Packed Bed Column for the Adsorption …
and adsorption has been communicated to have removed metal ions from water and
wastewater. O’Connell et al. [6] reported the advantages and inconveniences of the
enumerated techniques. Of these methods, however, the adsorption technique has
attracted the greatest attention because of its effectiveness in eliminating pollutants
of any kind, high selectivity, low cost and low energy consumption [7–9]. Studies
on various types of adsorbents have been conducted in recent years to develop an
adsorption technique having the consistency of recent options in the competitive environmental market. Though various types of adsorbent for example activated carbon
[10], bran [11], zeolite 4 A [12], magnetic graphene oxide [13], wheat [14], bio-chars
[15] and silicas [16] have been applied to remove metal ions, only a small number is
commercialize because of the high cost of the materials adsorbents. Chitosan adsorbent is a low-cost bio-polymer waste product mainly derived from crustaceans; it is
a partly deacetylated polymer purchased from chitin, high in protein, carotene and
calcium [17] carbonate. The presence of functional amines (–NH 2 ) and hydroxyl
group (–OH) in the backbone of chitosan gave it a distinctive character and quality.
Chitosan possesses structural and surface properties capable for the elimination of
aqueous metal ions from solutions and that is why it has been widely studied as
an adsorbent. Osifo et al. [18] comprehensively dealt with copper adsorption in a
packed bed of chitosan beads, where the adsorption capacity was determined to
be 3.8 mmol/g, while the shrinking core particle model was used to describe the
breakthrough curve for copper adsorption onto chitosan beads fairly well.
In this study, physical and chemical functionalization was introduced to enhance
the adsorption of metals properties of chitosan beads. Physical modification includes
the transformation of chitosan powder to beads for easy handling and better spreading
to binding sites [19]. On the other hand, chemical functionalization includes crosslinking of the beads to ensure stability in acid solution and practical grafting of functional groups to establish more active sites and increase the adsorption properties of
chitosan. To create chitosan beads in an industrial environment, column investigation
is extremely significant, and the majority of chitosan bead investigations reported
in the literature are also more of batch system with very minimal documentation
on metal regeneration; therefore, this study is very necessary. It has been reported
that knowledge obtained from the batch process cannot be used to remedy column
processes where the time of contact between adsorbate and adsorbent is not sufficient
for equilibrium to be established [20]. Batch procedures are often primarily limited
to remedying small quantities of contaminants. The use of packaged column systems
for large-scale wastewater remediation typically allows large amounts of contaminated water to be handled in a short period of time, and these devices can be scaled
up from the laboratory to a pilot plant project where the entire process can be easily
monitored [17]. However, the difference in concentration existing in the packed bed
column provides the driving force for the adsorption of metal ions, which results in
a satisfactory consistency of the contaminated water, and this process has been used
well by authors like [21, 22]. Several mathematical models have been developed and
applied to explain the packed bed column’s kinetic behaviour and also to predict
the breakthrough curve [2, 18]. The present study suggests a model of packed bed
column adsorption to estimate the breakthrough curve for adsorption of Cu(II) ions