Mathematical modeling and interpretation of equilibrium isotherms of Pb (II) from aqueous media by Chlorella pyrenoidosa immobilized in Luffa cylindrica

Autor: Ghania Henini, Mebrouk Djedid, Mokhtar Benalia, Imane Nouacer, Ykhlef Laidani
Rok vydání: 2021
Předmět:
Zdroj: Biomass Conversion and Biorefinery.
ISSN: 2190-6823
2190-6815
DOI: 10.1007/s13399-021-01722-4
Popis: New sorbent was prepared from unicellular green microalgal Chlorella pyrenoidosa (CP) immobilized in Luffa cylindrica (CP-LC) as a biosorbent for the removal of lead ions from aqueous media in a batch experiment mode. The prepared biosorbent was characterized by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). In the experimental design of the Pb (II) removal process, the equilibrium isotherms were studied and modeled. To select the best-fit isotherm model for this biological process, the experimental data were fitted in the eighteen different types of one-, two-, three-, four-, and five-parameter isotherm models. A comparison of non-linear models for selecting the optimum isotherm showed Fritz–Schlunder (V) model gives the most accurate fit to describe the experimental data, determined based on several error functions. Taking into account the outcome and in an attempt to optimize the equilibrium isotherms, the equation of Fritz-Schlunder (V) was modified to obtain more sophisticated model and more precision parameters values. As a consequence of such a developed model to existing mentioned ones, the mathematical model developed in this study is more suitable for predicting the equilibrium data. According to the results obtained, the evaluation of experimental data in terms of biosorption kinetics elucidated that the biosorption of Pb (II) by CP-LC well followed pseudo-second-order kinetics. The maximum biosorbent capacity of CP-LC was found to be 123 mg/g for 40 min at pH5. The calculated thermodynamic factors (∆G°, ∆H°, and ∆S°) indicated that the biosorption process was favorable, spontaneous, and exothermic at 298–318 K.
Databáze: OpenAIRE
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