Biosorption of Direct Red-31 and Direct Orange-26 dyes by rice husk: Application of factorial design analysis

The present work describes the biosorption potential of low cost and easily available rice husk for the adsorptive removal of Direct Red-31 and Direct Orange-26 textile dyes. In the present investigation a 5³ full factorial design analysis experiment was employed to optimize the process parameters for enhanced adsorptive removal of Direct Red-31 and Direct Orange-26 textile dyes from aqueous solution. Factorial experiments with three factors initial dye concentration, biosorbent dose and pH at five levels were conducted in duplicate. The biosorbent efficiency for the dyes was determined after 3 h of treatment at 30 °C using suitable size of biosorbent (0.255 mm). Analysis of variance (ANOVA), F-test and p-values were used to study the main, two ways and three ways interaction effects. The values of regression coefficients (R² = 0.999) for both dyes confirmed the good fitness of model. A maximum biosorption capacity of 57.88 and 36.14 mg/g was observed at pH 2 and 3 for Direct Red-31 and Direct Orange-26, respectively, with 125 mg/L dyes concentration. The most significant variable was found to be dyes initial concentration. Moreover, the decolorization of both direct dyes was also affected by salts, heavy metal ions and surfactants.     

The effect of pH on bioremediation potential for the removal of direct violet textile dye by Aspergillus niger

Alkaline and acidic media have been used in the textile dye industry, depending on the fabric nature. The bioremoval of textile direct violet dye by Aspergillus niger fungal strain was studied. The effect of pH on dye bioremoval was investigated at a pH range from 2 to 11. The direct violet dye bioremoval reached maximum with 92.4%, 64.0%, 91.4%, and 62.3 % at pH values of 2, 3, 8, and 9, respectively, at 24 h of incubation. The percentages of removal rate after 72 h incubation were 98.9, 97.3, 94.0, 95.0, 97.0, and 97.3 at pH 2, 3, 6, 7, 8, and 9, respectively. The optimum pH values were 2, 3, 8, and 9 for direct dye removal. At the end of the experiments, the treatment with fungal strain could reduce COD value of synthetic dye solution by 76-91%. Pseudo first and second order kinetic models were applied to evaluate differences in the biosorption rates and uptakes of textile dye. Pre-equilibrium biosorption of direct violet dye onto fungus under different dye concentrations followed a pseudo second order kinetic model with a high degree of correlation coefficients (R² > 0.99), and the calculated values of q_e nearly matched the experimental values of textile dye during the biotreatment process.     

Removal of Remazol Brilliant Blue R dye from aqueous solutions by adsorption onto immobilized Scenedesmus quadricauda: Equilibrium and kinetic modeling studies

The green algae Scenedesmus quadricauda was immobilized in alginate gel beads. The immobilized active (IASq) and heat inactivated S.quadricauda (IHISq) were used for the removal of Remazol Brilliant Blue R (CI 61200, Reactive Blue 19, RBBR) from aqueous solutions in the concentration range 25-200 mg L^− 1. At 150 mg L^− 1 initial dye concentration the IASq and IHISq exhibited the highest dye uptake capacity at 30 °C, at the initial pH value of 2.0. At the same initial dye concentration in the batch system the adsorption capacity was determined for IASq as 44.2; 44.9 and 45.7 mg g^− 1 in 30, 60 and 300 min, respectively. After 300 min the adsorption capacity hardly changed during the adsorption time. The IHISq of adsorption capacity was observed as 47.6; 47.8 and 48.3 mg g^− 1 in 30, 60 and 300 min, respectively. After 300 min the adsorption capacity was not changed for 24 h. The Langmuir, Freundlich, Temkin, Dubinin-Radushkevich and Flory-Huggins isotherm models were used to fit the equilibrium biosorption data. The Langmuir, Freundlich and Dubinin-Radushkevich equations have better coefficients than Temkin and Flory-Huggins equation describing the RBBR dye adsorption onto IASq and IHISq. The monomolecular biosorption capacity of the biomass was found to be 68 and 95.2 mg g^− 1 for IASq and IHISq, respectively. From the Dubinin-Radushkevich model, the mean free energy was calculated as 6.42-7.15 kJ mol^− 1 for IASq and IHISq, indicating that the biosorption of dye was taken place in physical adsorption reactions. The experimental data were also tested in terms of kinetic characteristics and it was determined that the biosorption process of dye was well explained with pseudo-second-order kinetics.     

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.     

Biosorption properties of dried Neurospora crassa for the removal of Burazol Blue ED dye

Biosorption potential of dried Neurospora crassa for Burazol Blue ED was studied with respect to pH, equilibrium time, biomass concentration and temperature to determine equilibrium and kinetic model parameters. The most suitable pH, equilibrium time and biomass concentration were determined as 1 ± 0.2, 60 min and 1.6 g L^− 1, respectively, at 20 °C ± 1.0. The equilibrium data was best described by the Langmuir isotherm model. The maximum biosorption capacity (q_m) of biomass obtained from the Langmuir fit was 110.1 mg g^− 1 biomass at 30 °C. The overall biosorption process was best described by the pseudo-second-order kinetic model. The biosorption process was found to be favored at higher temperatures.     

The study of the potential capability of sugar beet pulp on the removal efficiency of two cationic dyes

This study utilizes sugar beet pulp as a low-cost absorbent to remove two different cationic dyes, methylene blue and safranin, in aqueous solutions. The effects of operational parameters on the efficiency of dye removal including pH, adsorbent mass, initial dye concentration and contact time have been investigated. All sets of experiments were carried out in batch mode. For both dyes, the maximum absorption was reached at pH 10 while point zero charge was known to be at pH 6. Boehm method showed that the amount of the acidic and basic groups have been 0.4075 mmol g⁻¹ and 0.0089 mmol g⁻¹, respectively. Freundlich and Langmuir models were used to analyse the obtained experimental data. In comparison, Langmuir model was understood to be a better fit for the experimental data than Freundlich model. Pseudo first-order and pseudo second-order models were used to determine the adsorption kinetics and it was observed that pseudo second-order model was the most suited model for both dyes. The equilibrium state for both dyes was reached after 210 min of the absorption experiment with more than 93% removal of dyes. The absorption capacities were found to be 211 mg/g and 147 mg/g for methylene blue and safranin, respectively.     

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.     

Saccharomyces cerevisiae for the biosorption of basic dyes from binary component systems and the high order derivative spectrophotometric method for simultaneous analysis of Brilliant green and Methylene blue

In this work, biosorption of Brilliant green (BG) and Methylene blue (MB) dyes in binary mixture onto Saccharomyces cerevisiae were studied. pH at which the biosorption capacity of biomass is maximum was found to be 6 which is close to the pH of natural aqueous solutions. This is a big advantage of S. cerevisiae which makes it applicable for the technology of dye removal from natural aqueous dye solutions. Note that the time for the applied biosorption process for the dye removal is considerably short (about 5 min) which is a big improvement for the adsorption processes. This proves that the S. cerevisiae is a promising adsorbent. The BG and MB dyes were simultaneously analyzed using the fifth and fourth order derivative spectrophotometric method, respectively. Several isotherm models were applied to experimental data and the isotherm constants were calculated for BG and MB dyes. Among the applied models, Freundlich isotherm model showed best fit to the biosorption equilibrium data.     

Biosorption of hazardous textile dyes from aqueous solutions by hen feathers: Batch and column studies

The biosorption potential of hen feathers (HFs) to remove hazardous textile dyes, namely congo red (CR) and crystal violet (CV), from their aqueous solutions was investigated in batch and dynamic flow modes of operation. The effect of biosorption process parameters such as solution pH, initial dye concentration, temperature, feed flow rate and bed height was studied. Biosorption equilibrium data were well described by the Langmuir isotherm model. Kinetic studies at different temperatures showed that the rate of biosorption followed the pseudo second-order kinetics well. A thermodynamic study showed that biosorption of both CR and CV was spontaneous and endothermic. Breakthrough time increased with increase in bed height but decreased with increase in flow rate. The Thomas model showed good agreement with the dynamic flow experimental data. Overall, the results suggest the applicability of HFs as an efficient biosorbent for removal of carcinogenic textile dyes from aqueous media.     

Equilibrium,Thermodynamic and Kinetic Studies on Biosorption of Mercury from Aqueous Solution by Macrofungus (Lycoperdon perlatum) Biomass

The present research is to investigate the possibility of macrofungus Lycoperdon perlatum biomass, which is an easily available, renewable plant, low-cost, as a new biomass for the removal of mercury (Hg(II)) ions from aqueous solutions. The effects of various parameters like pH of solution, biomass concentration, contact time, and temperature were studied by the using the batch method. The Langmuir model adequately described the equilibrium data. The biosorption capacity of the biomass was found to be 107.4 mg · g^?1 at pH 6. The mean free energy value (10.9 kJ · mol^?1) obtained from the D–R model indicated that the biosorption of Hg(II) onto fungal biomass was taken place via chemical ion-exchange. Thermodynamic parameters showed that the biosorption of Hg(II) onto L. perlatum biomass was feasible, spontaneous, and exothermic in nature. The kinetic results showed that the biosorption of Hg(II) onto fungal biomass followed second-order kinetics. This work also shows that L. perlatum biomass can be an alternative to the expensive materials like ion exchange resins and activated carbon for the treatment of water and wastewater containing mercury ions due to its ability of selectivity and higher biosorption capacity and also being low cost material.     

Simultaneous multidye biosorption by chemically modified Sargassum glaucescens: Doehlert optimization and kinetic,equilibrium, and thermodynamic study in ternary system

Multidye biosorption of Sunset yellow (SY), Eosin yellow (EY) and Indigo carmine (IC) dyes onto chemically modified biomass of brown alga Sargassum glaucescens was studied. Principal component-wavelet neural network (PC-WNN) was applied for the simultaneous determination of anionic dye concentrations in ternary solutions. Experimental parameters were optimized using response surface methodology (RSM) with a Doehlert design. The optimal biosorption conditions were identified as biosorbent dosage 0.2 g L^?1, pH 3, and time 25 min. The maximum total biosorption capacity was 0.102 mmol g^?1. The Hill isotherm was the most suitable adsorption models in single and ternary systems. Scanning electron microscopy (SEM) and Fourier transform infrared (FT-IR) analysis confirmed possible interactions between biosorbent surface and dye molecules.     

Factorial experimental design for biosorption of iron and zinc using Typha domingensis phytomass

Typha domingensis phytomass was used as a biosorbent for metal ions removal from wastewater. A full 2³ factorial design of experiments was used to obtain the best conditions of biosorption of Fe³⁺ and Zn²⁺ from water solutions. The three factors considered were temperature, pH, and biosorbent dosage. Two levels for each factor were used; pH (2.5 and 6.0), temperature (25 and 45 °C), and phytomass loading weight (0.5 and 1 g/50 ml). Batch experiments were carried out using 50 ml solutions containing 10 mg/l Fe³⁺ and 4 mg/l Zn²⁺ simulating the concentration of those metals in a real wastewater effluent. The removal percentages of iron and zinc after 120 min of contact time were then evaluated. The results were analyzed statistically using the Minitab 15 statistical software to determine the most important factors affecting the metals removal efficiency. The pH was found to be the most significant factor for the two studied metal ions.     

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.     

Removal of acid dye (violet 54) and adsorption kinetics model of using musa spp. waste: A low-cost natural sorbent material

Experimental studies and biosorption kinetics of an intraparticle diffusion model for acid dye removal using a musa spp. waste sorbent were carried out to find the removal effects and dynamics of various operating parameters, such as initial dye concentration, sorbent dosage, pH and temperature. Experimental data were modeled with kinetic models and two biosorption isotherms of intraparticle diffusion models as well as the physiochemical data of sorbents characterized by SEM and FT-IR. Kinetic studies showed that the sorption process follows second-order rate kinetics with an average rate constant of 0.0018675 (g/mg·min). Thermodynamic parameters such as entropy of biosorption (ΔS⁰), enthalpy of biosorption (ΔH⁰) and Gibbs free energy of biosorption (ΔG⁰) were obtained and analyzed. Sorbent, musa spp. waste (banana peel) was characterized by FTIR and SEM. The results showed that musa spp. waste can be considered as potential sorbent for the sorption of acid violet 54 from dilute aqueous solution.     

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.     

Use of CaCl2 modified bentonite for removal of Congo red dye from aqueous solutions

CaCl₂ modified bentonite (BCa²⁺), a clean and cost-effective adsorbent with a basal spacing of 15.43 Å, was prepared for the removal of Congo red dye from water. It was effective for the removal of Congo red with a high adsorption capacity, and the adsorption was favored over a broad pH range (5-10). The pseudo-second-order kinetic model provided the best correlation of the experimental data. Adsorption isotherms indicated that sorption took place at specific homogeneous sites within the adsorbent. Furthermore, BCa²⁺ showed higher sorption capacity compared with other common materials used as adsorbents for Congo red dye. The results showed that BCa²⁺ could be employed as a low-cost material for the removal of Congo red from aqueous solutions.     

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.     

Adsorption behavior of copper ions on alga Jania adhaerens through SEM and FTIR analyses

Biomass of the alga Jania adhaerens was used for biosorption of copper ions from aqueous solutions. The effects of pH, copper concentration, biomass amount, and contact time on biosorption were investigated. For chemical modification of functional groups, FTIR and ICP analyses were performed to study the biosorption mechanism. Furthermore, the SEM images of pristine and copper-loaded biomass were also provided. The pseudo second order model described kinetics data appropriately. The adsorption isotherm was best fitted to the Langmuir model with the maximum adsorption capacity of 67 mg g^?1. Sulfonate, carboxyl, and amine functional groups affected the biosorption. Ion exchange was a mechanism of biosorption.     

Biosorption of silver from aqueous solutions using wine industry wastes

The potential of wine industry wastes (grape peel, seed, and stem) as alternative biosorbents to remove Ag from aqueous media was investigated in this work. Wine industry wastes were washed, lyophilized and pulverized to obtain the biosorbents. The powdered biosorbents were characterized in detail and several batch experiments were performed to found the most suitable conditions for Ag biosorption. Kinetic, equilibrium, and thermodynamic studies were also performed. The interactions Ag-biosorbent were elucidated by analyses before and after the biosorption. For all wastes, the maximum removal percentages were found using a biosorbent dosage of 3.0?g?L^?1 at pH of 7.0. The kinetic data were well represented by the pseudo-first-order model. The equilibrium was satisfactorily represented by the Sips model. The maximum biosorption capacities, found at 298?K, were: 41.7, 61.4, and 46.4?mg?g^?1 for grape peel, seed, and stem, respectively. Thermodynamically, the biosorption was a spontaneous, favorable, exothermic, and enthalpy-controlled process. The magnitude of ΔH⁰ indicated a physical sorption. These results showed that the wine industry wastes can be considered alternative efficient, low-cost, and eco-friendly biosorbents to remove Ag from aqueous media.     

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