ABSTRACT
The need to source for environmentally friendly
adsorbents for the removal of Cd2+, Pb2+, Hg2+ and As3+ from aqueous solution
was investigated in this study. Okra and kenafstems were tested as adsorbents
for the removal of Cd2+, Pb2+, Hg2+ and As3+. Modification of the adsorbents
was carried out using TolueneDiisocyanate and the effectiveness of the Modified
Okra Stem and Modified Kenaf Stem and Unmodified Okra stem and Unmodified
Kenafstem were investigated. At varying concentrations of metal ions (10, 20,
30 and 40 mg/L), the amount of Cd2+ adsorbed by Modified Okra Stem , Unmodified
Okra Stem , Modified Kenaf Stem and Unmodified Kenaf stem were in the
concentration ranges, (mg/L) 68.73 to 107.51, 72.99 to 81.73, 59.27 to 94.38
and 69.48 to 73.51 respectively. Corresponding ranges for adsorption of Pb2+
were 52.56 to 109.15, 60.83.37 to 83.37, 43.10 to 96.01 and 56.88 to 75.14
respectively. Hg2+ adsorption covered the ranges 56.01 to 89.28, 63.52 to
78.37, 41.81 to 72.18 and 3.31 to 59.26 mg/L. while that of As3+ (mg/L) were
58. 16, 34.36 to 71.58, 46.97 to 78.87 and from 11.03 to 66.89 respectively.
Generally, removal efficiency was observed to increase with increase in
concentration for the modified adsorbents (Modified Okra Stem and Modified Kenaf
Stem) but a sharp decrease in adsorption before subsequent increase were
observed for the unmodified adsorbents. Variation of equilibrium amount of
metal ions adsorbed with pH, temperature and contact time was observed to
follow similar trend, that is, the adsorption increases up to a maximum before
a slight decrease. A linear relationship was observed between equilibrium
amount of metal ion adsorbed and adsorbent dosage. Analysis of the Fourier
Transform Infra-Red spectra of the adsorbents before and after adsorption gave
evidences of interaction and involvement of functional groups in the adsorption
process showed some functional groups were missing, some were shifted, while
other new ones were formed. The adsorption characteristics obeyed the Langmuir,
Temkin, Freundlich and Harkins-Jura adsorption models. Thermodynamic data
reveals that adsorption mechanism is physisorption. However, pseudo first and
pseudo second order kinetics were excellently obeyed while the adsorption
process was proposed to be diffusion controlled through the observed fitness
ofthe adsorption data to intra particle diffusion. The Scanning Electron
Microscope profiles ofthe adsorbents before and after adsorption evidently
supported surface modification after adsorption. From the desorption studies,
the percentage desorption values showed that greater percentage of the adsorbed
metal ions on the adsorbents were held by weak forces supporting physisorption
as the mode of bonding ofthe metal ions on the surfaces. These results indicate
that the adsorbents are suitable for the removal ofCd2+, Pb2+, Hg2+, and As3+
from aqueous solution.
JULIANA, L (2025). Biosorption Of Some Heavy Metal Ions From Aqueous Solution Using Cellulose Pulp From Kenaf {Hibiscus Cannabinus L.) And Okra (Abelmoschus Esculentus} Stems:- Udoh, Juliana L. Mouau.afribary.org: Retrieved Jul 03, 2025, from https://repository.mouau.edu.ng/work/view/biosorption-of-some-heavy-metal-ions-from-aqueous-solution-using-cellulose-pulp-from-kenaf-hibiscus-cannabinus-l-and-okra-abelmoschus-esculentus-stems-udoh-juliana-l-7-2
LINUS, JULIANA. "Biosorption Of Some Heavy Metal Ions From Aqueous Solution Using Cellulose Pulp From Kenaf {Hibiscus Cannabinus L.) And Okra (Abelmoschus Esculentus} Stems:- Udoh, Juliana L" Mouau.afribary.org. Mouau.afribary.org, 03 Jul. 2025, https://repository.mouau.edu.ng/work/view/biosorption-of-some-heavy-metal-ions-from-aqueous-solution-using-cellulose-pulp-from-kenaf-hibiscus-cannabinus-l-and-okra-abelmoschus-esculentus-stems-udoh-juliana-l-7-2. Accessed 03 Jul. 2025.
LINUS, JULIANA. "Biosorption Of Some Heavy Metal Ions From Aqueous Solution Using Cellulose Pulp From Kenaf {Hibiscus Cannabinus L.) And Okra (Abelmoschus Esculentus} Stems:- Udoh, Juliana L". Mouau.afribary.org, Mouau.afribary.org, 03 Jul. 2025. Web. 03 Jul. 2025. < https://repository.mouau.edu.ng/work/view/biosorption-of-some-heavy-metal-ions-from-aqueous-solution-using-cellulose-pulp-from-kenaf-hibiscus-cannabinus-l-and-okra-abelmoschus-esculentus-stems-udoh-juliana-l-7-2 >.
LINUS, JULIANA. "Biosorption Of Some Heavy Metal Ions From Aqueous Solution Using Cellulose Pulp From Kenaf {Hibiscus Cannabinus L.) And Okra (Abelmoschus Esculentus} Stems:- Udoh, Juliana L" Mouau.afribary.org (2025). Accessed 03 Jul. 2025. https://repository.mouau.edu.ng/work/view/biosorption-of-some-heavy-metal-ions-from-aqueous-solution-using-cellulose-pulp-from-kenaf-hibiscus-cannabinus-l-and-okra-abelmoschus-esculentus-stems-udoh-juliana-l-7-2