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1.

Introduction

A biosorbent was developed by simple dried Agaricus bisporus (SDAB) and effectively used for the biosorption of cationic dyes, Crystal Violet and Brilliant Green.

Materials and methods

For the evaluation of the biosorbent system, all the batch equilibrium parameters like pH, biomass dose, contact time, and temperature were optimized to determine the decolorization efficiency of the biosorbent. The maximum yields of dye removal were achieved at pH 4.0 for Crystal Violet (CV) and pH 5.0 for Brilliant Green (BG), which are closer to their natural pH also.

Result and discussion

Equilibrium was established at 60 and 40 min for CV and BG, respectively. Pseudo first-order, pseudo second-order, and intraparticle-diffusion kinetic models were studied at different temperatures. Isotherm models such as Freundlich, Langmuir, and Dubinin–Radushkevich were also studied. Biosorption processes were successfully described by Langmuir isotherm model and the pseudo second-order kinetic model.

Conclusions

The biosorption capacity of A. bisporus over CV and BG were found as 21.74 and 12.16 mg gm?1. Thermodynamic parameters indicated that the CV and BG dye adsorption onto A. bisporus is spontaneous and exothermic in the single and ternary systems. Scanning electron microscopy, X-ray diffraction, and Fourier transform infrared spectroscopy were used for the surface morphology, crystalline structure of biosorbent, and dye–biosorbent interaction, respectively. This analysis of the biosorption data confirmed that these biosorption processes are ecofriendly and economical. Thus, this biomass system may be useful for the removal of contaminating cationic dyes.  相似文献   

2.
Reactive dyes account for one of the major sources of dye wastes in textile effluent. In this study, decolorization of the monoazo dye, Acid Orange 7 (AO7) by the Enterococcus faecalis strain ZL that isolated from a palm oil mill effluent treatment plant has been investigated. Decolorization efficiency of azo dye is greatly affected by the types of nutrients and the size of inoculum used. In this work, one-factor-at-a-time (method and response surface methodology (RSM) was applied to optimize these operational factors and also to study the combined interaction between them. Analysis of AO7 decolorization was done using Fourier transform infrared (FTIR) spectroscopy, desorption study, UV–Vis spectral analysis, field emission scanning electron microscopy (FESEM), and high performance liquid chromatography (HPLC). The optimum condition via RSM for the color removal of AO7 was found to be as follows: yeast extract, 0.1 %?w/v, glycerol concentration of 0.1 %?v/v, and inoculum density of 2.5 %?v/v at initial dye concentration of 100 mg/L at 37 °C. Decolorization efficiency of 98 % was achieved in only 5 h. The kinetic of AO7 decolorization was found to be first order with respect to dye concentration with a k value of 0.87/h. FTIR, desorption study, UV–Vis spectral analysis, FESEM, and HPLC findings indicated that the decolorization of AO7 was mainly due to the biosorption as well as biodegradation of the bacterial cells. In addition, HPLC analyses also showed the formation of sulfanilic acid as a possible degradation product of AO7 under facultative anaerobic condition. This study explored the ability of E. faecalis strain ZL in decolorizing AO7 by biosorption as well as biodegradation process.  相似文献   

3.
With the use of cost-effective natural materials, biosorption is considered as an ecological tool that is applied worldwide for the remediation of pollution. In this study, we proposed Lemna gibba biomass (LGB), a lignocellulosic sorbent material, for the removal of two textile dyes, Direct Red 89 (DR-89) and Reactive Green 12 (RG-12). These azo dyes commonly used in dying operations of natural and synthetic fibres are the most important pollutants produced in textile industry effluents. For this purpose, batch biosorption experiments were carried out to assess the efficacy of LGB on dye treatment by evaluating the effect of contact time, biomass dosage, and initial dye concentration. The results indicated that the bioremoval efficiency of 5 mg?L?1 DR-89 and RG-12 reached approximately 100 % after 20 min of the exposure time; however, the maximum biosorption of 50 mg?L?1 DR-89 and 15 mg?L?1 RG-12 was determined to be about 60 and 47 %, respectively. Fourier transform infrared spectroscopy used to explain the sorption mechanism showed that the functional groups of carboxylic acid and hydroxyl played a major role in the retention of these pollutants on the biomass surface. The modelling results using Freundlich, Langmuir, Temkin, Elovich, and Dubini Radushkevich (D-R) isotherms demonstrated that the DR-89 biosorption process was better described with the Langmuir theory (R 2?=?0.992) while the RG-12 biosorption process fitted well by the D-R isotherm equation (R 2?=?0.988). The maximum biosorption capacity was found to be 20.0 and 115.5 mg?g?1 for DR-89 and RG-12, respectively, showing a higher ability of duckweed biomass for the bioremoval of the green dye. The thermodynamic study showed that the dye biosorption was a spontaneous and endothermic process. The efficacy of using duckweed biomass for the bioremoval of the two dyes was limited to concentrations ≤50 mg?L?1, indicating that L. gibba biomass may be suitable in the refining step of textile effluent treatment.  相似文献   

4.
The aim of the present work is to develop an effective and inexpensive pollutant-removal technology using lignocellulosic fibers: Luffa cylindrica, for the biosorption of an anionic dye: alpacide blue. The influence of some experimental parameters such as pH, temperature, initial concentration of the polluted solution, and mass of the sorbent L. cylindrica on the biosorption of alpacide blue by L. cylindrica fibers has been investigated. Optimal parameters for maximum quantity of biosorption dye were achieved after 2 h of treatment in a batch system using an initial dye concentration of 20 mg/L, a mass of 1 g of L. cylindrica fibers, and pH 2. In these conditions, the quantity of dye retained is 2 mg/g and the retention rate is 78 %. Finally, a mathematical modeling of kinetics and isotherms has been used for mathematical modeling; the model of pseudo-second order is more appropriate to describe this phenomenon of biosorption. Concerning biosorption isotherms, the Freundlich model is the most appropriate for a biosorption of alpacide blue dye by L. cylindrica fibers.  相似文献   

5.
The present study was undertaken to determine the toxic effect of a lethal concentration of six different commercially used textile dyes on the 46th stage of Xenopus laevis tadpoles. The tadpoles were exposed to Astrazon Red FBL, Astrazon Blue FGRL, Remazol Red RR, Remazol Turquoise Blue G-A, Cibacron Red FN-3G, and Cibacron Blue FN-R for 168 h in static test conditions, and thus, 168-h median lethal concentrations (LC50s) of each dye were determined to be 0.35, 0.13, 112, 7, 359, and 15.8 mg/L, respectively. Also, to evaluate the sublethal effects of each dye, tadpoles were exposed to different concentrations of dyes (with respect to 168-h LC50s) for 24 h. The alteration of selected enzyme activities was tested. For this aim, glutathione S-transferase (GST), carboxylesterase, and lactate dehydrogenase (LDH) were assayed. After dye exposure, the GST induction or inhibition and LDH induction indicated some possible mechanisms of oxidative stress and deterioration in aerobic respiration processes induced by the tested dyes. Findings of the study suggest that selected biomarker enzymes are useful in understanding the toxic mechanisms of these dyes in X. laevis tadpoles as early warning indicators. Therefore, these selected biomarkers may evaluate the effect of environmental factors, such as textile dye effluents and other industrial pollutants, on amphibians in biomonitoring studies.  相似文献   

6.
7.
The purpose of this study is to examine on removal of arsenic from water by biosorption through potential application of herbal dye wastes. Four different flower dye residues (after extraction of natural dye) viz. Hibiscus rosasinensis, Rosa rosa, Tagetes erecta, and Canna indica were utilized successfully for the removal of arsenic from aqueous solution. Batch studies were carried out for various parameters viz. pH, sorbent dose, contact time, initial metal ion concentration, and temperature. Data were utilized for isothermal, kinetic, and thermodynamic studies. Scanning electron microscopy (SEM), energy-dispersive x-ray spectroscopy (EDAX), and Fourier transform infrared (FTIR) analyses of biomass were performed. The results showed that 1 g/100 ml for 5.0–5.5 h contact time at pH 6.0–7.5 with agitation rate 150 rpm provided 98, 96, 92, and 85 % maximum absorption of arsenic by R. rosa, H. rosasinensis, T. erecta, and C. indica, respectively, at initial concentration of 500 ppb. Data followed Langmuir isotherm showing sorption to be monolayer on heterogeneous surface of biosorbent. Negative values of ΔG° indicated spontaneous nature, whereas ΔH° indicates exothermic nature of system followed by pseudo-first-order adsorption kinetics. FTIR results showed apparent changes in functional group regions after metal chelation. SEM and EDAX analyses showed the changes in surface morphology of all test biosorbents. Herbal dye wastes, used as biosorbent, exhibited significant (85–98 %) removal of arsenic from aqueous solution. Hence, these biosorbents are cost-effective, easily available, eco-friendly, and comparatively more effective than other biosorbents already in use. These may be used to remove arsenic and other toxic metals from water.  相似文献   

8.
The aim of present study was to develop and evaluate sodium dodecyl sulfate (SDS) self-microemulsifying systems (SMES) for the removal of an anionic dye xylenol orange (XO) from its bulk aqueous media via liquid–liquid adsorption. The composition of SDS SMES was optimized by Box–Behnken statistical design for the maximum removal of XO from its aqueous solution. Various SDS formulations were prepared by spontaneous emulsification method and characterized for thermodynamic stability, self-microemulsification efficiency, droplet size, and viscosity. Adsorption studies were conducted at 8, 16, and 24 h by mixing small amounts of SDS formulations with relatively large amounts of bulk aqueous solution of XO. Droplet size and viscosity of SDS formulations were significantly influenced by oil phase concentration (triacetin), while surfactant concentration had little impact on droplet size and viscosity. However, the percentage of removal of XO was influenced by triacetin concentration, surfactant concentration, and adsorption time. Based on lowest droplet size (35.97 nm), lowest viscosity (29.62 cp), and highest percentage of removal efficiency (89.77 %), formulation F14, containing 2 % w/w of triacetin and 40 % w/w of surfactant mixture (20 % w/w of SDS and 20 % w/w of polyethylene glycol 400), was selected as an optimized formulation for the removal of XO from its bulk aqueous media after 16 h. These results indicated that SDS SMES could be suitable alternates of solid–liquid adsorption for the removal of toxic dyes such as XO from its aqueous solution through liquid–liquid adsorption.  相似文献   

9.
The present work investigates the potential use of metal hydroxides sludge (MHS) generated from hot dipping galvanizing plant for adsorption of Congo Red and Naphthol Green B dyes from aqueous solutions. Characterization of MHS included infrared and X-ray fluorescence analysis. The effect of shaking time, initial dye concentration, temperature, adsorbent dosage and pH has been investigated. The results of adsorption experiments indicate that the maximum capacity of Congo Red and Naphthol Green B dyes at equilibrium (q e) and percentage of removal at pH 6 are 40 mg/g, 93 %, and 10 mg/g, 52 %, respectively. Some kinetic models were used to illustrate the adsorption process of Congo Red and Naphthol Green B dyes using MHS waste. Thermodynamic parameters such as (ΔG, ΔS, and ΔH) were also determined.  相似文献   

10.
An agricultural by-product, natural wheat straw (NWS), was soaked in 1 % cationic surfactant (hexadecylpyridinium bromide, CPB) solution for 24 h (at 293 K), and modified wheat straw (MWS) was obtained. Analysis of FTIR, XFR, and nitrogen element showed that CPB was adsorbed onto surface of NWS. Then, MWS was used as adsorbent for the removal of light green dye (LG, anionic dye) from aqueous solution. The experiment was performed in batch and column mode at room temperature (293 K). Sodium chloride (up to 0.1 mol/L) existed in solution was not favor of LG dye adsorption. The equilibrium data were better described by Langmuir isotherm, and adsorption capacity of q m from Langmuir model was 70.01?±?3.39 mg/g. In fixed-bed column adsorption mode, the effects of initial LG concentration (30, 50, 70 mg/L) and flow rate (6.5, 9.0, 14.5 mL/min) on adsorption were presented. Thomas and modified dose–response models were used to predict the breakthrough curves using nonlinear analysis method, and both models can fit the breakthrough curves. Theoretical and experimental breakthrough curves were drawn and compared. The results implied that MWS can be used as adsorbent material to remove LG from aqueous solution.  相似文献   

11.
A significant proportion of xenobiotic recalcitrant azo dyes are being released in environment during carpet dyeing. The bacterial strain Stenotrophomonas sp. BHUSSp X2 was isolated from dye contaminated soil of carpet industry, Bhadohi, India. The isolated bacterial strain was identified morphologically, biochemically, and on the basis of 16S rRNA gene sequence. The isolate decolorized 97 % of C.I. Acid Red 1 (Acid RED G) at the concentration of 200 mg/l within 6 h under optimum static conditions (temperature ?35 °C, pH 8, and initial cell concentration 7?×?107 cell/ml). Drastic reduction in dye degradation rate was observed beyond initial dye concentration from 500 mg/l (90 %), and it reaches to 25 % at 1000 mg/l under same set of conditions. The analysis related to decolorization and degradation was done using UV-Vis spectrophotometer, HPLC, and FTIR, whereas the GC-MS technique was utilized for the identification of degradation products. Phytotoxicity analysis revealed that degradation products are less toxic as compared to the original dye.  相似文献   

12.
Biodegradation and biosorption of acid anthraquinone dye   总被引:16,自引:0,他引:16  
The acid anthraquinone dye Tectilon Blue (TB4R) is a major coloured component from the aqueous effluent of a carpet printing plant in Northern Ireland. The aerobic biodegradation of TB4R has been investigated experimentally in batch systems, using three strains of bacteria, namely, Bacillus gordonae (NCIMB 12553), Bacillus benzeovorans (NCIMB 12555) and Pseudomonas putida (NCIMB 9776). All three strains successfully decolourised the dye, and results were correlated using Michaelis-Menten kinetic theory. A recalculation of the reaction rate constants, to account for biosorption, gave an accurate simulation of the colour removal over a 24-h period. Up to 19% of the decolorisation was found to be caused by biosorption of the dye onto the biomass, with the majority of the decolorisation caused by utilisation of the dye by the bacteria. The reaction rate was found to be intermediate between zero and first order at dye concentrations of 200-1000 mg/l.  相似文献   

13.
Bioremediation of textile dyestuffs under solid-state fermentation (SSF) using industrial wastes as substrate pose an economically feasible, promising, and eco-friendly alternative. The purpose of this study was to adsorb Red M5B dye, a sample of dyes mixture and a real textile effluent on distillery industry waste-yeast biomass (DIW-YB) and its further bioremediation using Bacillus cereus EBT1 under SSF. Textile dyestuffs were allowed to adsorb on DIW-YB. DIW-YB adsorbed dyestuffs were decolorized under SSF by using B. cereus. Enzyme analysis was carried out to ensure decolorization of Red M5B. Metabolites after dye degradation were analyzed using UV–Vis spectroscopy, FTIR, HPLC, and GC-MS. DIW-YB showed adsorption of Red M5B, dyes mixture and a textile wastewater sample up to 87, 70, and 81 %, respectively. DIW-YB adsorbed Red M5B was decolorized up to 98 % by B. cereus in 36 h. Whereas B. cereus could effectively reduce American Dye Manufacture Institute value from DIW-YB adsorbed mixture of textile dyes and textile wastewater up to 70 and 100 %, respectively. Induction of extracellular enzymes such as laccase and azoreductase suggests their involvement in dye degradation. Repeated utilization of DIW-YB showed consistent adsorption and ADMI removal from textile wastewater up to seven cycles. HPLC and FTIR analysis confirms the biodegradation of Red M5B. GC-MS analysis revealed the formation of new metabolites. B. cereus has potential to bioremediate adsorbed textile dyestuffs on DIW-YB. B. cereus along with DIW-YB showed enhanced decolorization performance in tray bioreactor which suggests its potential for large-scale treatment procedures.  相似文献   

14.
In this present study, the biosorption of Cr(VI) and Zn(II) ions from synthetic aqueous solution on defatted J atropha oil cake (DJOC) was investigated. The effect of various process parameters such as the initial pH, adsorbent dosage, initial metal ion concentration and contact time has been studied in batch-stirred experiments. Maximum removal of Cr(VI) and Zn(II) ions in aqueous solution was observed at pH 2.0 and pH. 5.0, respectively. The removal efficiency of Cr(VI) and Zn(II) ions from the aqueous solution was found to be 72.56 and 79.81 %, respectively, for initial metal ion concentration of 500 mg/L at 6 g/L dosage concentration. The biosorbent was characterized by Fourier transform infrared, scanning electron microscopy and zero point charge. Equilibrium data were fitted to the Langmuir, Freundlich, Temkin and Dubinin–Radushkevich isotherm models and the best fit is found to be with the Freundlich isotherm for both Cr(VI) and Zn(II) metal ions. The kinetic data obtained at different metal ion concentration have been analysed using the pseudo-first-order, pseudo-second-order and intraparticle diffusion models and were found to follow the pseudo-second-order kinetic model. The values of mass transfer diffusion coefficients (D e) were determined by Boyd model and compared with literature values. Various thermodynamic parameters, such as ΔG°, ΔH° and ΔS°, were analysed using the equilibrium constant values (K e) obtained from experimental data at different temperatures. The results showed that biosorption of Cr(VI) and Zn(II) ions onto the DJOC system is more spontaneous and exothermic in nature. The results indicate that DJOC was shown to be a promising adsorbent for the removal of Cr(VI) and Zn(II) ions from aqueous solution.  相似文献   

15.
The main purpose of this study was to investigate the effectiveness of Lactobacillus 12 and Lactobacillus rhamnosus as both cells and biomasses for the removal of dye from real textile dyeing wastewater. The removal experiments were conducted according to the Box–Behnken experimental design, and the regression equations for the removal of dye were determined by the Minitab 14 program. The optimum variables were found to be 10 g/?L biomass concentration for biomasses, 3 for initial pH of the solution, and 20 °C for temperature with an observed dye removal efficiency of about 60 and 80 % with L. 12 and L. rhamnosus biomasses, respectively. Scanning electron microscopy and Fourier transform infrared spectroscopy images also showed that the biomass characteristics studied were favored by the sorption of the dye from the textile industry wastewater. Consequently, these biomasses may be considered as good biosorbents due to their effective yields and the lower cost of the removal of dyes from the effluents of the textile dyeing house.  相似文献   

16.
17.
Naturally occurring kind of weathered and oxidised young brown coal called oxihumolite was used for an adsorptive removal of basic (Methylene Blue, Malachite Green) as well as acid (Egacid Orange, Midlon Black) dyes from waters. It was shown that both kinds of dyes can be sorbed onto oxihumolite. The maximum sorption capacities determined from the parameters of Langmuir isotherms ranged from 0.070 mmol g-1 (for Midlon Black) to 0.278 mmol g-1 (for Malachite Green) and did not differ significantly for basic and acid dyes. The dye sorption (except of Midlon Black) increased in the presence of inorganic salt. Non-ionic surfactants, and surfactants bearing the same charge as the dye exhibited only a minor effect on the dye sorption, whereas oppositely charged surfactants enhanced the dye sorption to a certain extent. The pH value of the aqueous phase exhibited rather pronounced effect on the sorption of acid dyes causing a suppression of the sorption with increasing pH. The sorption of basic dyes, on the other hand, remained almost unchanged in the examined pH range. Oxihumolite is recommended for the treatment of acid wastewaters because of its limited stability in alkaline aqueous solutions.  相似文献   

18.
In this work, the efficiency of electrochemical oxidation (EO) was investigated for removing a dye mixture containing Novacron Yellow (NY) and Remazol Red (RR) in aqueous solutions using platinum supported on titanium (Ti/Pt) as anode. Different current densities (20, 40 and 60 mA cm?2) and temperatures (25, 40 and 60 °C) were studied during electrochemical treatment. After that, the EO of each of these dyes was separately investigated. The EO of each of these dyes was performed, varying only the current density and keeping the same temperature (25 °C). The elimination of colour was monitored by UV-visible spectroscopy, and the degradation of organic compounds was analysed by means of chemical oxygen demand (COD). Data obtained from the analysis of the dye mixture showed that the EO process was effective in colour removal, in which more than 90 % was removed. In the case of COD removal, the application of a current density greater than 40 mA cm?2 favoured the oxygen evolution reaction, and no complete oxidation was achieved. Regarding the analysis of individual anodic oxidation dyes, it was appreciated that the data for the NY were very close to the results obtained for the oxidation of the dye mixture while the RR dye achieved higher colour removal but lower COD elimination. These results suggest that the oxidation efficiency is dependent on the nature of the organic molecule, and it was confirmed by the intermediates identified. Figure
Chemical structures of a NY and b RR  相似文献   

19.

Purpose

Biodegradation and biodecolorization of Drimarene blue K2RL (anthraquinone) dye by a fungal isolate Aspergillus flavus SA2 was studied in lab-scale immobilized fluidized bed bioreactor (FBR) system.

Method

Fungus was immobilized on 0.2-mm sand particles. The reactor operation was carried out at room temperature and pH?5.0 in continuous flow mode with increasing concentrations (50, 100, 150, 200, 300, 500?mg?l?1) of dye in simulated textile effluent on the 1st, 2nd, 5th, 8th, 11th, and 14th days. The reactors were run on fill, react, settle, and draw mode, with hydraulic retention time (HRT) of 24?C72?h. Total run time for reactor operation was 17?days.

Results

The average overall biological oxygen demand (BOD), chemical oxygen demand (COD), and color removal in the FBR system were up to 85.57%, 84.70%, and 71.3%, respectively, with 50-mg?l?1 initial dye concentration and HRT of 24?h. Reductions in BOD and COD levels along with color removal proved that the mechanism of biodecolorization and biodegradation occurred simultaneously. HPLC and LC?CMS analysis identified phthalic acid, benzoic acid, 1, 4-dihydroxyanthraquinone, 2,3-dihydro-9,10-dihydroxy-1,4-anthracenedione, and catechol as degradation products of Drimarene blue K2RL dye. Phytotoxicity analysis of bioreactor treatments provided evidence for the production of less toxic metabolites in comparison to the parent dye.

Conclusion

The present fluidized bed bioreactor setup with indigenously isolated fungal strain in its immobilized form is efficiently able to convert the parent toxic dye into less toxic by-products.  相似文献   

20.
The aim of this study is the treatment of Basic Red 29 (BR29) dye solution using hybrid iron-aluminum electrodes by electrocoagulation and electro-Fenton methods. The effect of current density, initial pH, supporting electrolyte, H2O2, and initial dye concentration on dye removal efficiency was investigated, and the best experimental conditions were obtained. Time-coarse variation of UV-Vis spectra and toxicity and chemical oxygen demand (COD) removal were also examined at the best experimental conditions. Both systems were found very successful for the removal of BR29 dye. The removal efficiency of >95 % for BR29 dye solution was reached easily in a short time. At the best experimental conditions, for the initial BR29 concentration of 100 mg/L, >95 % BR29 dye and 71.43 % COD removal were obtained after 20 and 40 min of electrolysis, respectively. Additionally, toxicity results for electro-Fenton treatment of 100 mg/L BR29 were also very promising. According to the results obtained, although electro-Fenton is more effective, both systems can be used successfully to treat textile wastewater including dyes.  相似文献   

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