Biosorption of lac dye by the red marine alga Gracilaria tenuistipitata: biosorption kinetics,isotherms, and thermodynamic parameters

The hypothesis that the dried, ground biomass of the red marine alga Gracilaria tenuistipitata could be used for the efficient removal of lac dye from aqueous solution was assessed in this work. The effects of parameters such as initial pH, biosorbent dosage, contact time, initial dye concentration, and temperature on the biosorption capacity of the dye were investigated. Equilibrium data were analysed using Langmuir, Freundlich, and Temkin isotherm models, and the Freundlich model provided the highest coefficient of determination values. Biosorption kinetic data were successfully described with a pseudo‐second‐order model at initial dye concentrations of 50, 80, 100, and 120 mg l^?1. The thermodynamic parameters of biosorption – enthalpy change (?H° = ?30.64 kJ mol^?1), free energy change (?G° = 4.32 kJ mol^?1 at 303 K to 7.78 kJ mol^?1 at 333 K), and entropy change (?S° = ?115.38 J mol^?1 K^?1) – were determined. The negative value of the enthalpy change and positive values of the free energy change indicate that the biosorption process is exothermic and non‐spontaneous. The negative value of the entropy change is consistent with decreased randomness at the solid–liquid interface with dye biosorption. Attenuated total reflectance–Fourier transform infrared spectroscopic analysis confirmed the presence of lac dye on the G. tenuistipitata material. The efficiency of lac dye removal by this biomass material at 20 g l^?1 and with an initial dye concentration of 50 mg l^?1 in acidic solution was 71%, which indicated its potential usefulness as a new dye biosorbent.     

Efficient biosorption of a reactive dye from contaminated media by Neurospora sitophila cells—Zea mays silk tissue biomass system

BACKGROUND: A filamentous fungus Neurospora sitophila was immobilized in Zea mays silk tissue and the prepared system was employed as a new biosorbent for the treatment of reactive dye contaminated solutions. RESULTS: Decolorization potential of the biosorbent system was investigated in batch and continuous mode operations. Design parameters such as pH, biomass dosage, contact time, temperature, dye concentration and flow rate were investigated. Batch mode equilibrium data were analyzed kinetically to determine the rate constants. The process followed the pseudo‐second‐order kinetic model. The thermodynamics of the biosorption indicated the spontaneous and endothermic nature of the process. Biosorption was well described by the Langmuir isotherm model, with a maximum monolayer biosorption capacity of 105.33 mg g^?1. Relatively good dynamic flow decolorization potential was observed for the biosorbent system in synthetic and real wastewater conditions. Flow mode regeneration studies over ten consecutive cycles indicated that the suggested biosorbent maintained consistently high biosorption yield, above 70%. The possible dye‐biosorbent interaction mechanism was also confirmed by zeta potential, FTIR, SEM and EDX analysis. CONCLUSION: High biosorption capacity and regeneration potential suggest that the new biosorbent system can be used as an alternative and low‐cost biomaterial for the treatment of reactive dye contaminated solutions. Copyright © 2011 Society of Chemical Industry     

Application of tobacco hairy roots for the removal of malachite green from aqueous solutions: Experimental design,kinetic, equilibrium,and thermodynamic studies

Tobacco hairy roots (THR) were used to evaluate its potential for the biosorption and removal of malachite green (MG) from aqueous solutions. A 3² full factorial design was applied to study the effects of pH and THR concentration on the biosorption capacity. Under the optimal conditions (pH of 7.0 and THR concentration of 1?g?L^?1), dye removal efficiency was around 92%. Experimental data obtained from kinetic studies demonstrated good concordance with the pseudo-second-order model. Equilibrium studies were developed and the data were evaluated by Langmuir, Freundlich, and Sips models, being the Sips model the most adequate (maximum biosorption capacity of 277.2?mg?g^?1). Thermodynamically, the biosorption of MG on THR proved to be endothermic, spontaneous, and favorable. Desorption was feasible under acidic conditions and the biosorbent could be reused three times. THR was tested in simulated effluent and the removal percentage was 87%, demonstrating that this material is a promising biosorbent which can be used to treat colored wastewaters.     

Nickel removal characteristics of an immobilized macro fungus: equilibrium,kinetic and mechanism analysis of the biosorption

BACKGROUND: An immobilized new biosorbent was prepared from macro fungi Lactarius salmonicolor for the effective removal of nickel ions from aqueous media. Operating conditions were optimized as functions of initial pH, agitation time, sorbent amount and dynamic flow rate. Immobilization and biosorption mechanism were examined and the developed biosorbent was tested for the removal of nickel ions from real wastewater. RESULTS: Biosorption performance of the biomass continuously increased in the pH range 2.0–8.0. The coverage of the biosorbent surface by silica gel resulted in a significant increase in biosorption yield of nickel ions. The highest nickel loading capacity was obtained as 114.44 mg g^?1 using a relatively small amount of immobilized biosorbent. Biosorption equilibrium time was recorded as 5 min. Experimental data were analyzed by different isotherm and kinetic models. Infrared spectroscopy, scanning electron microscopy and X‐ray energy dispersive analysis confirmed the process. The sorbent exhibited relatively good recovery potential in dynamic flow mode studies. Biosorption capacity of immobilized biosorbent was noted as 14.90 mg g^?1 in real wastewater. CONCLUSION: Silica gel immobilized biomass of L. salmonicolor is to be a low cost and potential biosorbent with high biosorption capacity for the removal of contaminating nickel from aqueous media. © 2012 Society of Chemical Industry     

Effect of pre‐treatments on the biosorption of Chromium (VI) ions by the dead biomass of Rhizopus arrhizus

BACKGROUND: This work fulfils the need to develop an eco‐friendly biosorbent, elucidating the mechanism of biosorption. Removal of Cr(VI) by Rhizopus arrhizus was investigated in batch mode. Enhancement in the performance of the biosorbent was attempted by pre‐treating the biomass with inorganic and organic acids, chelating agent, cross‐linker and an organic solvent followed by autoclaving. The surface characterization of the biomass was carried out by potentiometric titration, surface area analysis, infrared spectroscopy, chemical modification of the biomass and scanning electron microscopy. RESULTS: All the physico‐chemical treatments of the biosorbent improved Cr(VI) uptake compared with the native biomass (21.72 mg g^?1). The highest biosorption capacity (31.52 mg g^?1) was achieved after pre‐treating the biomass with 0.5 mol L^?1 HNO₃ followed by autoclaving. Surface characterization of the biomass using pH_zpc, potentiometry and Fourier transform infrared (FTIR) analysis revealed the role of amino and carboxyl groups in Cr(VI) removal by electrostatic attraction. Chemical modification of amino and carboxyl groups significantly decreased Cr(VI) uptake capacity confirming their role in biosorption. SEM analysis showed adsorption of Cr(VI) on the biosorbent surface. CONCLUSION: Rhizopus arrhizus biomass proved to be an effective and low cost alternative biosorbent for removal of Cr(VI) from aqueous solutions. Copyright © 2011 Society of Chemical Industry     

Biosorption of a Basic Dye from Aqueous Solutions by Euphorbia rigida

Abstract

In this study, the biosorption of Basic Blue 9 (BB9) dye from aqueous solutions onto a biomass of Euphorbia rigida was examined by means of the initial biosorbate concentration, biosorbent amount, particle size, and pH. Biosorption of BB9 onto E. rigida increases with both the initial biosorbate concentration and biosorbent amount, whereas decreases with the increasing particle size. The experimental data indicated that the biosorption isotherms are well‐described by the Langmuir equilibrium isotherm equation at 20, 30, and 40°C. Maximum biosorption capacity was 3.28×10^?4 mol g^?1 at 40°C. The biosorption kinetics of BB9 obeys the pseudo‐second‐order kinetic model. The thermodynamic parameters such as ΔG°, ΔH° and ΔS° were calculated to estimate the nature of biosorption. These experimental results have indicated that E. rigida has the potential to act as a biosorbent for the removal of Basic Blue 9 from aqueous solutions.     

Biosorption of methylene blue from aqueous solution by softstem bulrush (Scirpus tabernaemontani Gmel.)

BACKGROUND: The removal of methylene blue from aqueous solution was studied using softstem bulrush (Scirpus tabernaemontani Gmel.) as the biosorbent. The effects of various parameters including contact time, biosorbent dosage, ionic strength and solution pH on the biosorption were investigated. RESULTS: The sorption capacity increased with an increase in biosorbent dosage and a decrease in ionic strength. The equilibrium time was found to be 240 min for full equilibration. Pseudo‐first‐order, pseudo‐second‐order, Bangham equation and intraparticle diffusion models were applied to fit the kinetic data, and the results showed that the sorption process followed the pseudo‐second‐order model. Equilibrium data conformed to Langmuir and Redlich–Peterson isotherm models, with a maximum monolayer biosorption capacity of 53.8 mg g^?1 for the Langmuir isotherm at 18 °C. The value of ΔG was estimated to be ? 29.24 kJ mol^?1, indicating the spontaneous nature of the biosorption. The biosorption process was strongly pH‐dependent and favourable at alkaline pH. CONCLUSION: Softstem bulrush, which is readily available and inexpensive, could be employed as a promising biosorbent for the removal of dye. Copyright © 2008 Society of Chemical Industry     

Development of chitosan/Spirulina bio‐blend films and its biosorption potential for dyes

Chitosan/Spirulina bio‐blends (CSBB) in films form were developed to be an alternative/renewable biosorbent, able to remove anionic and cationic dyes from aqueous solutions. CSBB potential as biosorbent was investigated for cationic dye Methylene Blue (MB), and anionic dyes Tartrazine Yellow (TY) and Reactive Black 5 (RB5). Chitosan and Spirulina samples were obtained and characterized, and CSBB films were prepared with different chitosan/Spirulina ratios. The CSBB films characteristics, as, mechanical properties, thermal profile, crystallinity, functional groups, morphology, and biosorption potential were strongly dependent of chitosan/Spirulina ratio. CSBB films preserved its mechanical structures at pH from 4.0 to 8.0. The biosorption capacities were 120, 110, and 100 mg g^?1 for RB5, TY, and MB, respectively. The increase of chitosan amount favored the TY and RB5 biosorption; however, the increase of Spirulina amount favored the MB biosorption. Thus, the CSBB in film form is a renewable biosorbent suitable to remove anionic and cationic dyes from aqueous solutions. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44580.     

Biosorption behaviour of alginate-immobilized Trichoderma asperellum,a common microfungi in single- and multi-metal systems

Alginate-immobilized Trichoderma asperellum were superior in adsorbing metals in single-metal systems compared to multi-metal systems. Higher amounts of Cu(II), Zn(II) and Cd(II) were adsorbed in single-metal systems with 72.00, 20.61 and 51.77 mg metal removed g^?1 biosorbent, respectively, compared to multi-metal systems. On the contrary, only Pb(II) (112.70 mg g^?1 biosorbent) was removed more efficiently in multi-metal systems. Both biosorbents showed similar biosorption behaviour, with higher uptakes of Zn(II) < Cd(II) < Cu(II) < Pb(II) in both single- and multi-metal systems. This was attributed to the carboxyl and hydroxyl functional groups on the surface of alginate.     

Biosorption potential of Neurospora crassa cells for decolorization of Acid Red 57 (AR57) dye

Biosorption of Acid Red 57 (AR57) on to Neurospora crassa was studied with variation of pH, contact time, biosorbent and dye concentrations and temperature to determine equilibrium and kinetic models. The AR57 biosorption was fast and equilibrium was attained within 40 min. Langmuir, Freundlich and Dubinin–Radushkevich (D–R) isotherm models were applied to experimental equilibrium data for AR57 biosorption at various temperatures. The equilibrium data fitted very well to all the equilibrium models in the studied concentration range of AR57. Maximum biosorption capacity (q_max) of AR57 on to N. crassa was 2.16 × 10^?4 mol g^?1 at 20 °C. The kinetics of biosorption of AR57 were analyzed and rate constants were derived. The overall biosorption process was best described by a pseudo‐second‐order kinetic model. The changes in Gibbs free energy, enthalpy and entropy of biosorption were also evaluated for the biosorption of AR57 on to N. crassa. The results indicate that the biosorption was spontaneous and exothermic in nature. Copyright © 2006 Society of Chemical Industry     

Fixed-bed column performance of methylene blue biosorption by Luffa cylindrica: statistical and mathematical modeling

Abstract

This study aimed to investigate the adsorption capacity of Iranian Luffa cylindrica as a natural lignocellulosic adsorbent for biosorption of methylene blue (MB) using a fixed-bed column. The response surface methodology based on central composite design was used to evaluate the interactive effects of three major operating parameters (inlet MB concentration, Luffa dosage, and feed flow rate) on the dye removal percentage (response variable). The significance of the proposed quadratic model was validated by a high coefficient of determination (R²?=?0.995) and a low p value (<0.001). The optimum biosorption conditions were determined as inlet MB concentration 38.66?mg?L^?1, Luffa dosage 2.78?g, and feed flow rate 5?mL?min^?1, and the maximum MB removal efficiency was founded to be 51% (q_max?=?21.4?mg?g^?1) at optimum conditions. The breakthrough curves were predicted by the Adams–Bohart and Thomas models using nonlinear regression analysis, whereas the experimental data fitted well with the Thomas model (R²?≈?0.96–0.98). Further surface modification studies enabled us to achieve the maximum MB removal efficiency of 77% (q_max?=?46.58?mg?g^?1) with NaOH-modified Luffa, which is attributed to the intensification of the negatively charged surface of the base-modified adsorbent with hydroxyl groups. The nature of biosorbent–dye interactions was also evaluated by FTIR analysis. The highest desorption performance of MB from Luffa fibers was obtained with HCl solution reaching a desorbed amount of q_des?=?130.5?mg in the column studies. The ion exchange is introduced as the dominant biosorption mechanism of MB onto Luffa fibers in this study.     

Biosorption of Direct Red 28 (Congo Red) from Aqueous Solutions by Eggshells: Batch and Column Studies

The feasibility of using eggshells as a low-cost biosorbent for the removal of Direct Red 28 (DR 28) from aqueous solutions was studied in batch and dynamic flow modes of operation. The effect of biosorption process variables such as particle size, solution pH, initial dye concentration, contact time, temperature, feed flow rate, and bed height were investigated. Both the Langmuir and Freundlich isotherm models exhibited excellent fit to the equilibrium biosorption data. Optimum pH (6.0), particle size (<250 µm), initial dye concentration (50 mg g^?1), temperature (313 K), and contact time (240 min) gave maximum monolayer biosorption capacity of 69.45 mg g^?1 which was higher than those of many sorbent materials. Pseudo-second-order kinetic model depicted the biosorption kinetics accurately. Thermodynamic study confirmed the spontaneous and endothermic nature of the biosorption process. Breakthrough time increased with increase in the bed height but decreased with increase in flow rate. Overall, batch and continuous mode data suggest the applicability of eggshells as an environment friendly and efficient biosorbent for removal of DR 28 from aqueous media.     

Removal of Reactive Dyes using Magnetically Separable Trametes versicolor Cells as a New Composite Biosorbent

Magnetically modified Trametes versicolor cells were used for biosorption of Reactive Blue 13 (RB13), Reactive Yellow 85 (RY85) and Reactive Violet 1 (RV1). Percent biosorption values and maximum adsorption capacities of 98.30% and 135.35 mg g^?1 for RB13, 96.02% and 125 mg g^?1 for RY85, and 98.56% and 227.27 mg g^?1 for RV1 were observed under optimal conditions. The biosorption of all dyes was exothermic in nature. The biosorbent was characterized using scanning electron microscopy, energy-dispersive X-ray spectroscopy, and magnetic force microscopy. The Langmuir model was found to be most suitable for describing the biosorption of all dyestuffs. The experimental data fitted very well the pseudo second order kinetic model.     

Equilibrium,Kinetic, and Thermodynamic Studies on the Biosorption of Selenium (IV) Ions onto Ganoderma Lucidum Biomass

The capacity of Ganoderma lucidum biomass for biosorption of selenium (IV) ions from aqueous solution was studied in a batch mode. In this study the effects of operating parameters such as solution pH, adsorbent dosage, initial metal concentration, contact time, and temperature were investigated. The adsorption capacity of G. lucidum was found to be 126.99 mg g^?1. The biosorption follows pseudo-first order kinetics and the isotherms fit well to both Langmuir and Freundlich isotherm models. Isotherms have been used to determine thermodynamic parameters of the process, that is, free energy, enthalpy, and entropy changes. Furthermore, the biosorbent was characterized by scanning electron microscopy and FT-IR analysis. FT-IR analysis of fungal biomass shows the presence of amino, carboxyl, hydroxyl, and carbonyl groups, which were responsible for the biosorption of selenium(IV) ions. The results indicated that the biomass of G. lucidum is an efficient biosorbent for the removal of selenium (IV) ions from aqueous solutions.     

Zinc (II) ion recovery by biosorption onto powdered waste sludge (PWS): effects of operating conditions

Powdered waste sludge (PWS) obtained from a paint industry wastewater treatment plant and pretreated with 1% H₂O₂ was used for biosorption of Zn(II) ions from aqueous solution. The effects of operating conditions, pH, temperature, agitation speed, PWS particle size, Zn ion and PWS concentrations on the extent of Zn ion biosorption were investigated in batch experiments. The optimum pH resulting in maximum Zn ion biosorption was found to be pH = 5, since Zn ions precipitated in the form of Zn(OH)₂ at pH levels above 5. The rate and extent of Zn ion biosorption increased with temperature between 25 and 50 °C, although biosorption was not strongly sensitive to temperature variations since the activation energy was low at 4.5 kcal mol^?1. Biosorbent particle size had a significant effect on Zn ion biosorption, yielding high percentage Zn removals at small particle sizes (D_p < 100 µm) or large surface areas of PWS. Agitation speed also considerably affected the extent of Zn ion removal, and should be above 150 rpm in order to obtain a high rate. The extent of Zn ion biosorption was also affected by the initial Zn ion and PWS concentrations. At constant biosorbent (PWS) concentration, percentage Zn ion removal decreased, but the biosorbed Zn concentration increased with increasing initial Zn ion concentrations. However, at constant initial Zn concentrations, percentage Zn removal increased, but the biosorbed Zn ion concentration decreased with increasing adsorbent (PWS) concentration. With a maximum Zn ion biosorption capacity of 168 mg g^?1 powdered waste sludge was proven to be an effective biosorbent compared to other biosorbents. Copyright © 2006 Society of Chemical Industry     

Equilibrium,Thermodynamic, and Kinetic Studies on Trichoderma viride Biomass as Biosorbent for the Removal of Cu(II) from Water

Equilibrium, thermodynamic, and kinetic studies on the biosorption of Cu(II) using biomass, Trichoderma viride were carried out. The biosorbent was characterized by Fourier transform infrared spectroscopy and Scanning Electron Microscopy. The Langmuir and Freundlich isotherm models were applied to describe the biosorption process. The influence of pH, the biomass dosage, the contact time, the initial metal ion concentration, and the temperature of the solution on the biosorption was studied. The maximum Cu(II) biosorption was attained at pH 5. The equilibrium data were better fit by the Langmuir isotherm model than by the Freundlich isotherm. The maximum biosorption capacity of T. viride biomass was found to be 19.6 mg/g for Cu(II). The kinetic studies indicated that the biosorption of Cu(II) followed the pseudo-second-order model. The calculated thermodynamic parameters, Gibbs-free energy (ΔG^o), enthalpy (ΔH^o), and entropy (ΔS^o) showed that the biosorption of Cu(II) onto T. viride biomass was spontaneous and endothermic. It can be concluded that the T. viride biomass has the potential as an effective and low-cost biosorbent for Cu(II) removal from aqueous solutions.     

Adsorption behaviors of crystal violet from aqueous solution using Anatolian black pine (Pinus nigra Arnold.): kinetic and equilibrium studies

ABSTRACT

In this study, Anatolian black pine (ABP, Pinus nigra Arnold.) was evaluated as biosorbent for removal of crystal violet (CV) from aqueous solution. The influence of operational parameters including solution pH, initial CV concentration, biosorbent dosage, contact time, and temperature were studied in batch systems. The adsorption data followed well Langmuir isotherm with a maximum biosorption capacity of 12.36 mg/g. The equilibrium data were better fitted with pseudo-second-order kinetic model (R² ? 0.99). Moreover, the thermodynamic parameters indicated that the CV biosorption was feasible, spontaneous, and endothermic process. This study showed that ABP (Pinus nigra Arnold.) can be used to remove CV from aqueous solutions.     

Dye adsorption and desorption properties of Mentha pulegium in single and binary systems

This article deals with the dye adsorption and desorption properties of Mentha pulegium (MP) from single and binary (mixture of dyes) systems. Direct Red 80 (DR80) and Acid Black 26 (AB26) were used as model dyes. The Fourier transform infrared (FTIR) was used to investigate the biosorbent characteristics. The effects of biosorbent dosage, contact time, dye concentration, salt, and pH on dye removal were studied. The biosorption isotherms, kinetics, and thermodynamic were studied. In addition, dye desorption was carried out to study adsorbent recovery. The results showed that the isotherm data of single and binary systems of dyes followed the Langmuir isotherm. The adsorption kinetic of the dyes was found to conform to a pseudosecond order kinetic model. Desorption tests showed maximum dye releasing of 97% for DR80 and 95% for AB26 in single system and 92% for DR80 and 94% for AB26 in binary system of dyes at pH 12. The thermodynamic data showed that the biosorption process is spontaneous, endothermic, and a physisorption reaction. It can be concluded that MP is an ecofriendly biosorbent to remove dyes from single and binary systems. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011