Optimum Biosorption Conditions Research Articles

Biosorption of hexavalent chromium by raw and acid-treated green alga Oedogonium hatei from aqueous solutions

The hexavalent chromium, Cr(VI), biosorption by raw and acid-treated Oedogonium hatei were studied from aqueous solutions. Batch experiments were conducted to determine the biosorption properties of the biomass. The optimum conditions of biosorption were found to be: a biomass dose of 0.8 g/L, contact time of 110 min, pH and temperature 2.0 and 318 K respectively. Both Langmuir and Freundlich isotherm equations could fit the equilibrium data. Under the optimal conditions, the biosorption capacities of the raw and acid-treated algae were 31 and 35.2 mg Cr(VI) per g of dry adsorbent, respectively. Thermodynamic parameters showed that the adsorption of Cr(VI) onto algal biomass was feasible, spontaneous and endothermic under studied conditions. The pseudo-first-order kinetic model adequately describe the kinetic data in comparison to second-order model and the process involving rate-controlling step is much complex involving both boundary layer and intra-particle diffusion processes. The physical and chemical properties of the biosorbent were determined and the nature of biomass–metal ions interactions were evaluated by FTIR analysis, which showed the participation of COOH, OH and NH 2 groups in the biosorption process. Biosorbents could be regenerated using 0.1 M NaOH solution, with up to 75% recovery. Thus, the biomass used in this work proved to be effective materials for the treatment of chromium bearing aqueous solutions.

Equilibrium and thermodynamic studies on biosorption of Pb(II) onto Candida albicans biomass

Biosorption of Pb(II) ions from aqueous solutions was studied in a batch system by using Candida albicans. The optimum conditions of biosorption were determined by investigating the initial metal ion concentration, contact time, temperature, biosorbent dose and pH. The extent of metal ion removed increased with increasing contact time, initial metal ion concentration and temperature. Biosorption equilibrium time was observed in 30 min. The Freundlich and Langmuir adsorption models were used for the mathematical description of biosorption equilibrium and isotherm constants were also evaluated. The maximum biosorption capacity of Pb(II) on C. albicans was determined as 828.50 ± 1.05, 831.26 ± 1.30 and 833.33 ± 1.12 mg g −1, respectively, at different temperatures (25, 35 and 45 °C). Biosorption showed pseudo second-order rate kinetics at different initial concentration of Pb(II) and different temperatures. The activation energy of the biosorption ( E a) was estimated as 59.04 kJ mol −1 from Arrhenius equation. Using the equilibrium constant value obtained at different temperatures, the thermodynamic properties of the biosorption (Δ G°, Δ H° and Δ S°) were also determined. The results showed that biosorption of Pb(II) ions on C. albicans were endothermic and spontaneous. The optimum initial pH for Pb(II) was determined as pH 5.0. FTIR spectral analysis of Pb(II) adsorbed and unadsorbed C. albicans biomass was also discussed.

Biosorption of lead and nickel by living and non-living cells of Pseudomonas aeruginosa ASU 6a

The optimum conditions for biosorption and bioaccumulation of lead and nickel were investigated by using a tolerant bacterial strain isolated from El-Malah canal, Assiut, Egypt, and identified as Pseudomonas aeruginosa ASU 6a. The experimental adsorption data were fitted towards the models postulated by Langmuir and Freundlich isotherm equations. The binding capacity by living cells is significantly lower than that of dead cells. The maximum biosorption capacities for lead and nickel obtained by using non-living cells and living cells were 123, 113.6 and 79, 70 mg/g, respectively. The biosorptive mechanism was confirmed by IR analysis and from the identification nature of acidic and basic sites. Moreover, the postulated mechanism was found to depend mainly on ionic interaction and complex formation.

Biosorption of lead(II) from aqueous solutions by non-living algal biomass Oedogonium sp. and Nostoc sp.—A comparative study

Industrial wastewaters containing heavy metals pose a major environmental problem that needs to be remedied. The present study reports the ability of two non-living (dried) fresh water algae, Oedogonium sp. and Nostoc sp. to remove lead(II) from aqueous solutions in batch system under varying range of pH (2.99–7.04), contact time (5–300 min), biosorbent dose (0.1–0.8 g/L), and initial metal ion concentrations (100 and 200 mg/L). The optimum conditions for lead biosorption are almost same for the two algal biomass Oedogonium sp. and Nostoc sp. (pH 5.0, contact time 90 and 70 min, biosorbent dose 0.5 g/L and initial Pb(II) concentration 200 mg/L) however, the biomass of Oedogonium sp. was found to be more suitable than Nostoc sp. for the development of an efficient biosorbent for the removal of lead(II) from aqueous solutions, as it showed higher values of q e adsorption capacity (145.0 mg/g for Oedogonium sp. and 93.5 mg/g for Nostoc sp.). The equilibrium data fitted well in the Langmuir isotherms than the Freundlich isotherm, thus proving monolayer adsorption of lead on both the algal biomass. Analysis of data shows that the process involves second-order kinetics and thermodynamic treatment of equilibrium data shows endothermic nature of the adsorption process. The spectrum of FTIR confirms that the amino and carboxyl groups on the surface of algal biomass were the main adsorption sites for lead removal. Both the biosorbents could be regenerated using 0.1 mol/L HCl solution, with upto 90% recovery. The biosorbents were reused in five biosorption–desorption cycles without a significant loss in biosorption capacity. Thus, this study demonstrated that both the algal biomass could be used as an efficient biosorbents for the treatment of lead(II) bearing wastewater streams.

Biosorption of Cd(II) and Cr(III) from aqueous solution by moss (Hylocomium splendens) biomass: Equilibrium, kinetic and thermodynamic studies

The biosorption characteristics of Cd(II) and Cr(III) ions from aqueous solution using the moss ( Hylocomium splendens ) biomass were investigated in terms of equilibrium, kinetics and thermodynamics. Optimum biosorption conditions were determined as a function of pH, biomass dosage, contact time, and temperature. Langmuir, Freundlich and Dubinin–Radushkevich (D–R) models were applied to describe the biosorption isotherm of the metal ions by H. splendens biomass. Langmuir model fitted the equilibrium data better than the Freundlich isotherm. The maximum biosorption capacity ( q m ) of H. splendens biomass was found to be 32.5 mg/g for Cd(II) ion and 42.1 mg/g for Cr(III) ion. The mean free energy values evaluated from the D–R model indicated that the biosorption of Cd(II) and Cr(III) onto H. splendens biomass was taken place by chemical ion-exchange. The calculated thermodynamic parameters, Δ G °, Δ H ° and Δ S ° showed that the biosorption of Cd(II) and Cr(III) ions onto H. splendens biomass was feasible, spontaneous and exothermic under examined conditions. Experimental data were also tested in terms of biosorption kinetics using pseudo-first-order and pseudo-second-order kinetic models. The results showed that the biosorption processes of both metal ions followed well pseudo-second-order kinetics.

Application of response surface methodology for optimization of lead biosorption in an aqueous solution by Aspergillus niger

Response surface methodology was applied to optimize the removal of lead ion by Aspergillus niger in an aqueous solution. Experiments were conducted based on a rotatable central composite design (CCD) and analyzed using response surface methodology (RSM). The biosorption process was investigated as a function of three independent factors viz. initial solution pH (2.8–7.2), initial lead concentration (8–30 mg/l) and biomass dosage (1.6–6 g/l). The optimum conditions for the lead biosorption were found to be 3.44, 19.28 mg/l and 3.74 g/l, respectively, for initial solution pH, initial lead ion concentration and biomass dosage. Lead biosorption capacity on dead A. niger fungal biomass was enhanced by pretreatment using NaOH. Under these conditions, maximum biosorption capacity of the biomass for removal of lead ions was obtained to 96.21%. The desirability function was used to evaluate all the factors and response in the biosorption experiments in order to find an optimum point where the desired conditions could be obtained. The A. niger particles with clean surface and high porosity may have application as biosorbent for heavy metal removal from wastewater effluents.

Biosorption of Cr (VI) from aqueous solutions by biomass of Agaricus bisporus

In this study, biosorption of Cr (VI) ion was investigated by using biomass of Agaricus bisporus (a species of mushroom) in a temperature and shaking speed controlled shaker. The effect of shaking speed, biomass concentration, initial metal ion concentration and initial pH on biosorption yield was determined and the fitness of biosorption data for Freundlich and Langmuir adsorption models was investigated. Optimum biosorption conditions were found to be pH 1, C 0 = 50 mg/l, m = 10 g/l, shaking speed = 150 rpm, T = 20 °C Cr (VI), respectively. It was found that biosorption of Cr (VI) ions onto biomass of A. bisporus was better suitable to Freundlich adsorption model than Langmuir adsorption model. The correlation coefficients for the second-order kinetic model obtained were found to be 0.999 for all concentrations. These indicate that the biosorption system studied belongs to the second-order kinetic model.

Biosorption of Pb(II) and Cr(III) from aqueous solution by lichen ( Parmelina tiliaceae) biomass

The biosorption characteristics of Pb(II) and Cr(III) ions from aqueous solution using the lichen ( Parmelina tiliaceae) biomass were investigated. Optimum biosorption conditions were determined as a function of pH, biomass dosage, contact time, and temperature. Langmuir, Freundlich and Dubinin–Radushkevich (D–R) models were applied to describe the biosorption isotherm of the metal ions by P. tiliaceae biomass. Langmuir model fitted the equilibrium data better than the Freundlich isotherm. The monolayer biosorption capacity of P. tiliaceae biomass for Pb(II) and Cr(III) ions was found to be 75.8 mg/g and 52.1 mg/g, respectively. From the D–R isotherm model, the mean free energy was calculated as 12.7 kJ/mol for Pb(II) biosorption and 10.5 kJ/mol for Cr(III) biosorption, indicating that the biosorption of both metal ions was taken place by chemical ion-exchange. The calculated thermodynamic parameters (Δ G°, Δ H° and Δ S°) showed that the biosorption of Pb(II) and Cr(III) ions onto P. tiliaceae biomass was feasible, spontaneous and exothermic under examined conditions. Experimental data were also tested in terms of biosorption kinetics using pseudo-first-order and pseudo-second-order kinetic models. The results showed that the biosorption processes of both metal ions followed well pseudo-second-order kinetics.

Investigation of nickel(II) biosorption on Enteromorpha prolifera: Optimization using response surface analysis

In this study, the biosorption of nickel(II) ions on Enteromorpha prolifera, a green algae, was investigated in a batch system. The single and combined effects of operating parameters such as initial pH, temperature, initial metal ion concentration and biosorbent concentration on the biosorption of nickel(II) ions on E. prolifera were analyzed using response surface methodology (RSM). The optimum biosorption conditions were determined as initial pH 4.3, temperature 27 °C, biosorbent concentration 1.2 g/L and initial nickel(II) ion concentration 100 mg/L. At optimum biosorption conditions, the biosorption capacity of E. prolifera for nickel(II) ions was found to be 36.8 mg/g after 120 min biosorption. The Langmuir and Freundlich isotherm models were applied to the equilibrium data and defined very well both isotherm models. The monolayer coverage capacity of E. prolifera for nickel(II) ions was found as 65.7 mg/g. In order to examine the rate limiting step of nickel(II) biosorption, such as the mass transfer and chemical reaction kinetics, the intraparticle diffusion model, external diffusion model and the pseudo second order kinetic model were tested with the experimental data. It was found that for both contributes to the actual biosorption process. The pseudo second order kinetic model described the nickel(II) biosorption process with a good fitting.

The investigation of lead removal by biosorption: An application at storage battery industry wastewaters

Lead is present in different types of industrial effluents, being responsible for environmental pollution. Biosorption has attracted the attention in recent years as an alternative to conventional methods for heavy metal removal from water and wastewater. The biosorption of Pb(II) ions present in the storage battery industry wastewaters intensively, by Rhizopus arrhizus has been investigated in this study. This microorganism has been preferred since its biosorption feature was well known. A detailed study was conducted for the removal of Pb(II) ions which was very toxic even in low quantities to the receiving environment, from storage battery industry wastewater by biosorption system as advanced treatment technique, and to investigate the effects of the several parameters on its removal. The average Pb(II) ions concentration in the storage battery industry wastewater found 3.0 mg/L and reducing this value below 0.5 mg/L was aimed. In this study, the effects of the media conditions (pH, temperature, biomass concentration) on the biosorption of Pb(II) ions to R. arrhizus have been investigated in a batch reactor. Optimum biosorption conditions have been found of initial pH 4.5, temperature 30 °C and biomass concentration 1.0 g/L. The maximum biosorption capacity was obtained as 2.643 mg Pb(II)/g microorganism.

Biosorption characteristics of Bacillus sp. ATS-2 immobilized in silica gel for removal of Pb(II)

The bacterial strain Bacillus sp. ATS-2 isolated from Pb(II) polluted soil was immobilized with a silica matrix and Pb(II) biosorption properties of immobilized biosorbent were examined. Optimum biosorption conditions were investigated in the fixed bed column with the variation in the parameters of pH, bed lenght, flow rate and influent concentration. The Pb(II) biosorption equilibrium was attained within 60 min and the maximum biosorption yield for silica gel immobilized Bacillus sp. ATS-2 was determined as 91.73% at pH 4.0. The higher biosorption yields were observed at flow rates of 60 and 180 ml h −1. The optimum bed length for the column was found as 10 cm. Data obtained from batch studies were evaluated by Freundlich, Langmuir and Dubinin–Radushkevich (D–R) isotherm models. The maximum monolayer capacity of Bacillus sp. ATS-2 for Pb(II) was 2.36 × 10 −5 mol g −1. The involvement of the functional groups on the surface of immobilized cells in biosorption process was also evaluated by FTIR spectral analysis.

Removal of lead and copper ions from aqueous solutions by bacterial strain isolated from soil

Biosorption of Pb(II) and Cu(II) ions from aqueous solutions has been studied in a batch system by using a bacterial strain isolated from metal polluted soil. The bacterial strain was identified as Bacillus sp. The optimum conditions of biosorption were determined by investigating the initial pH, contact time and the initial concentrations of metal ions at constant temperature (25 ◦ C). The maximum biosorption of the metal ions was observed at pH 3.0 ± 0.1 for Pb(II) and pH 5.0 ± 0.1 for Cu(II) ions. Biosorption equilibrium times for Pb(II) and Cu(II) ions were observed in 15 and 30 min, respectively. The maximum biosorption capacities of Pb(II) and Cu(II) ions on Bacillus sp. were determined to be 92.27 ± 1.17 mg g −1 at 250 mg l −1 concentration and 16.25 ± 1.64 mg g −1 at 200 mg l −1 concentration, respectively. The experimental adsorption data were fitted to Langmuir isotherm model. Competition of metal ions during biosorption was investigated in binary metal solutions. The interactions between metal ions and functional groups on the cell wall surface of the biomass were confirmed by FTIR, SEM and EDAX analysis. The results indicated that bacterial isolate Bacillus sp. is a suitable biosorbent for the removal of Pb(II) and Cu(II) ions from aqueous solutions. © 2005 Published by Elsevier B.V.

Biosorption of Acid Red 274 (AR 274) on Dicranella varia: Determination of equilibrium and kinetic model parameters

The biosorption of Acid Red 274 (AR 274) from aqueous solution on Dicranella varia was studied in a batch system with respect to initial pH and dye concentration, temperature, biosorbent concentration and stirring rate. The optimum biosorption conditions were found to be initial pH 3.0, the initial dye concentration 700 mg l −1, biosorbent concentration 0.5 g l −1 and temperature 30 °C, where the stirring rate was not an effective parameter on the biosorption capacity of D. varia. The Langmuir, Freundlich, Redlich–Peterson and Temkin isotherm models were applied to the experimental data and isotherm constants were calculated more precisely using Polymath 4.1 program. Equilibrium data fitted better to the Langmuir model than the other models according to ERRSQ analysis. The maximum monolayer adsorption capacity of D. varia for AR 274 was 2000 mg g −1 for optimum initial pH and temperature. To determine the steps affecting the uptake mechanism, the experimental data were evaluated using a boundary layer diffusion model, Weber–Morris model and a pseudo-second order kinetic model. Enthalpy and entropy changes were also calculated and it is concluded that the biosorption of AR 274 from aqueous solution on D. varia was exothermic in nature.

Biosorption of Cd 2+ from aqueous solution by a NaOH-treated bacterial dead Streptomyces rimosus biomass

The cadmium biosorption capacity of a Streptomyces rimosus biomass treated with NaOH (0.1 M) was studied in the batch mode. After pretreatment of biomass at the ambient temperature, optimum conditions of biosorption were found to be: a biomass particle size between 50 and 160 μm, an average saturation contact time of 1 h, a biomass concentration and a stirring speed in the range of 2.5–3 g L −1 and 200–250 rpm, respectively. The external mass transfer was found to be the controlling step in the overall sorption process. The equilibrium data could be fitted by Langmuir isotherm equation. Under these optimal conditions, a biosorption capacity of 63.3 mg Cd 2+/g biomass was obtained.

Biosorption of Ni 2+ from aqueous solution by a NaOH-treated bacterial dead Streptomyces rimosus biomass

The nickel biosorption capacity of a Streptomyces rimosus biomass treated with NaOH (0.1 M) was studied in the batch mode. After pre-treatment of biomass at the ambient temperature, optimum conditions of biosorption were found to be: a biomass particle size between 50 and 160 μm, an average saturation contact time of 2 h, a biomass concentration of 3 g L −1 and a stirring speed of 250 rpm. The external mass transfer was found to be the controlling step in the overall sorption process. The equilibrium data could be fitted by Langmuir isotherm equation. Under these optimal conditions a biosorption capacity of 32.6 mg Ni 2+/g biomass was obtained.

Biosorption of Ni2+ from aqueous solution by a NaOH-treated bacterial dead Streptomyces rimosus biomass

The nickel biosorption capacity of a Streptomyces rimosus biomass treated with NaOH (0.1 M) was studied in the batch mode. After pre-treatment of biomass at the ambient temperature, optimum conditions of biosorption were found to be: a biomass particle size between 50 and 160 μm, an average saturation contact time of 2 h, a biomass concentration of 3 g L −1 and a stirring speed of 250 rpm. The external mass transfer was found to be the controlling step in the overall sorption process. The equilibrium data could be fitted by Langmuir isotherm equation. Under these optimal conditions a biosorption capacity of 32.6 mg Ni 2+ /g biomass was obtained.

Biosorption of lead (II) from aqueous solution by a bacterial dead Streptomyces rimosus biomass

The lead biosorption capacity of a Streptomyces rimosus biomass treated with NaOH (0.1 M) was studied in the batch mode. After pretreatment of biomass at the ambient temperature, optimum conditions of biosorption were found to be: a biomass particle size between 50 and 160 μm, an average contact time of 3 h, a biomass concentration of 3 g/l and a stirring speed of 250 rpm. The equilibrium data could be fitted by Langmuir isotherm equation. Under these optimal conditions, 135 mg Pb 2+/g biomass was obtained.

Simultaneous biosorption of cadmium (II) and lead (II) ions by pretreated biomass of Phanerochaete chrysosporium

Abstract The article extends the study on the treatment of heavy metal wastewater by considering the competitive biosorption of two metal ions together, Cd (II) and Pb (II), by Phanerochaete chrysosporium, a filamentous fungus, under optimum biosorption conditions determined for each metal ion. The effects of the presence of one metal ion on the biosorption of the other metal ion were investigated in terms of equilibrium isotherm and adsorption yield. Experimental results indicated that the uptake capacity and adsorption yield of one metal ion were reduced by the presence of the other metal ion. In addition, comparisons between biosorption of Pb (II) ions and Cd (II) ions by the biomass of P. chrysosporium in the binary solution could lead to the conclusion that biosorption of Pb (II) ions was preferential to that of Cd (II) ions. In the single-ion situation, biosorption of Cd (II) ions and Pb (II) ions had the optimum adsorption conditions in common, which were the solution pH 4.5, temperature 27 °C. The maximum uptake obtained at initial concentration of Cd (II) ions 50 mg l−1, could reach 15.2 mg g−1, for Pb (II) ions it could reach 12.34 mg g−1. Both the adsorption equilibrium data fitted the Freundlich model well. Moreover, the uptake of Cd (II) ions had a less sensitive dependence on temperature than that of Pb (II) ions.

Biosorption of Fe 3+ from aqueous solution by a bacterial dead Streptomyces rimosus biomass

The iron biosorption capacity of a Streptomyces rimosus biomass treated with NaOH was studied in batch mode. After pretreatment of biomass at the ambient temperature, optimum conditions of biosorption were found to be: a biomass particle size between 50 and 160 μm, an average saturation contact time of 4 h, a biomass concentration of 3 g/l and a stirring speed of 250 rpm. The equilibrium data could be fitted by Langmuir isotherm equation. Under these optimal conditions, 122 mg Fe /g biomass were fixed.

Batch zinc biosorption by a bacterial nonliving Streptomyces rimosus biomass

The zinc biosorption capacity of a Streptomyces rimosus biomass was studied in the batch mode. After a heat pretreatment, optimum conditions of biosorption were found to be: an average saturation contact time of 4 h, a biomass particle size between 140 and 250 μm, the ambient temperature, a stirring speed of 250 rpm, and pH of 7.5. The equilibrium data could be fitted by a Langmuir isotherm equation. Under these optimal conditions, up to 30 mg Zn/g biomass, was fixed. Moreover, additional chemical treatment of the biomass by NaOH (1 mol/L), increased the biosorption capacity of about 80 mg Zn/g biomass.