Biosorption of Re(VII) from Batch Solutions and Industrial Effluents by Cyanobacteria Spirulina platensis

Abstract

The potential of Spirulina platensis biomass for rhenium ions removal from both batch solutions and industrial effluents is evaluated. The effect of pH, contact time, initial metal concentration, and the temperature of biosorbent treatment on the biosorption process is investigated. The maximum biosorption capacity of 142.9 mg g−1 rhenium is achieved at pH 2, sorbent dosage 0.05 g, and temperature of biosorbent treatment 30 °C. The equilibrium data are well fitted by Langmuir and Freundlich adsorption isotherm models (R2 = 0.99), while the pseudo‐second order kinetic model (R2 > 0.99) is found to describe better the kinetic data. Fourier‐transform infrared (FTIR) spectra shows that rhenium biosorption takes place through two mechanisms: ionic interactions of perrhenate anions with amide and amino‐groups and/or binding to organic functional groups of the cell surface. The rhenium bound to the biomass can be effectively stripped using NH4OH (8%) and the biomass is effectively used for three sorption–desorption cycles. In the case of industrial effluents, S. platensis biomass shows relatively high rhenium removal efficiency (51–55%). S. platensis biomass can be efficiently applied for rhenium removal from industrial effluents.

Treatment of Rhenium-Containing Effluents Using Environmentally Friendly Sorbent, Saccharomyces cerevisiae Biomass

“…With the increase in the pH values, the efficiency of rhenium removal significantly decreased, reaching 5% at pH 6.0. Such behavior of rhenium removal is in agreement with our previous study, where cyanobacteria Spirulina platensis was used as a biosorbent [ 11 ]. Maximum sorption of rhenium on Bacillus sp.…”

“…Yeast sorption capacity was compared with the values available in the literature for other types of sorbents ( Table 4 ). The adsorption capacity of yeast biomass was lower than values obtained in works [ 9 , 11 , 33 ] and higher than in other studies presented in Table 4 . However, it should be mentioned that experiments were performed with different experimental conditions, and in the main part of the previously conducted research, rhenium removal from a single-element system was studied.…”

“…Pseudo-first-order (6), pseudo-second-order (7), and Elovich models (8) were applied to describe the kinetics of the metal sorption on yeast biomass. Non-linear regression was used to estimate parameters of adsorption, since it allows minimizing the error distribution between the experimental and predicted data [ 11 ]. …”

“…Equilibrium data were fitted using non-linearized Langmuir, Freundlich, and Temkin isotherm models (9)–(11): where C e is equilibrium concentration (mg/L), q m is maximum adsorption capacity (mg/g), b is Langmuir adsorption constant (L/mg), K F and n are Freundlich equation constants, 1/ b T manifests the sorption potential of the sorbent, a T is Temkin constant, R is the universal gas constant (8.314 J K −1 mol –1 ), and T is the temperature (K) [ 11 , 13 ].…”

“…Information about the application of biological sorbents for rhenium removal is very limited. In our previous work, the microalga Spirulina platensis was used for rhenium removal from a single-component batch system and two rhenium-containing industrial effluents [ 11 ]. Mashkani and co-authors [ 12 ] tested more than 100 bacterial strains, and only Bacillus sp.…”