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Octa Journal of Environmental Research (2015)
  • Satish Bhalerao, Wilson College
The biosorption studies for effective removal of cadmium (II) ions from aqueous solutions using
orange rind (Citrus sinensis L. Osbeck), cost effective biosorbent, was carried out in batch system. FTIR
analysis of biosorbent confirmed that carboxyl, hydroxyl, carbonyl group which was responsible for
biosorption of cadmium (II) ions. The SEM represents porous structure with surface area. The effects of
operational factors including solution pH, biosorbent dose, initial cadmium (II) ions concentration, contact
time and temperature were studied. The optimum solution pH for cadmium (II) ions biosorption by
biosorbent was 7.0 with the optimal removal 80.30 %. The biosorbent dose 5 mg/ml was enough for optimal
removal of 65.15 %. The biosorption process was relatively fast and equilibrium was achieved after 90
minutes of contact. The experimental equilibrium biosorption data were analysed by four widely used twoparameters
Langmuir, Freundlich, Dubinin-Kaganer-Redushkevich (DKR) and Temkin isotherm models.
Langmuir isotherm model provided a better fit with the experimental data than Freundlich, Temkin and
Dubinin-Kaganer-Redushkevich (DKR) isotherm models by high correlation coefficient value (R2 = 0.911).
The maximum adsorption capacity determined from Langmuir isotherm was found to be 83.33 mg/g of
biosorbent. Simple kinetic models such as pseudo-first-order, pseudo-second-order, Elovich equation and
Weber and Morris intra-particle diffusion rate equation were employed to determine the adsorption
mechanism. Results clearly indicates that the pseudo-second-order kinetic model (R2 = 0.998) was found to
be correlate the experimental data strongest than other three kinetic models and this suggests that chemical
adsorption process was more dominant. Thermodynamic study revealed that the biosorption process was
spontaneous, endothermic and increasing randomness of the solid solution interfaces. Orange rind (Citrus
sinensis L. Osbeck) was successfully used for the biosorption studies of cadmium (II) ions from aqueous
solutions and can be applied in waste water technology for remediation of heavy metal contaminatio
  • Adsorption isotherms; Adsorption kinetics; FTIR; SEM; Thermodynamic study.
Publication Date
Summer March 16, 2015
Citation Information
Satish Bhalerao. "04-150224_0301.pdf" Octa Journal of Environmental Research Vol. 3 Iss. 1 (2015) p. 28 - 40 ISSN: ISSN 2321 3655
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