Decolorization Of Reactive Blue 19 Research Articles

Improved application of immobilized Enterobacter cloacae into a bio-based polymer for Reactive Blue 19 removal, an eco-friendly advancement in potential decolorizing systems.

The widespread use of highly complex synthetic dyes like reactive dyes in the textile industry has some adverse environmental impacts and deserves close attention. Biological treatment of these effluents utilizing various species of bacteria with remarkable efficiency in dye removal is still considered promising. Our current study deals with immobilizing an isolated bacterial strain into calcium alginate (Ca/Alg) gel beads and using it to treat pernicious pollutants like synthetic dyes. A potential Reactive Blue 19 (RB19)-degrading Enterobacter cloacae strain A1 was isolated from the Kashan textile industry and was characterized by 16S rDNA gene sequencing. The decolorization ability of strain A1 was assessed by time-based studies using free bacterial cells/immobilized in Ca/Alg. Based on the results of the 16S rDNA gene sequencing, it appears that strain A1 belonged to E.cloacae, with a 99.74% similarity. The findings suggest that immobilized strain A1 accomplished maximum decolorization activity compared with the free cells. The immobilized strain could utterly decompose and decolorize 0.05 mg/mL of RB19 within 48 h, while the free bacterial strain decolorized RB19 within 5 days. Moreover, Ca/Alg gel beads can maintain their efficiency for over three decolorization cycles. Further infrared spectroscopy (FTIR) and gas chromatograph mass spectrometer (GC/MS) investigation declared complete RB19 decomposition on reaction products. Artemia salina was used to investigate the toxicity of dye and its degraded metabolites. The LC50 values signified the pure dye as very toxic with 0.01 mg/mL concentration, while after-treatment products showed no toxic effect on larvae. This immobilization technique increased the applicability of bacterial strain for dye removal. It was beneficial for the decolorization of RB19 from textile wastewater due to a remarkable reduction in time. Notably, strain A1-immobilized beads can maintain their activity for three consecutive decolorization cycles without a considerable decrease in efficiency. PRACTITIONER POINTS: The remarkable capacity of immobilized Enterobacter cloacae strain A1 for Reactive Blue 19 (RB19) removal Immobilized A1 strain showed two-fold higher removal than free one over 48 h A promising method for enhancing RB19 decolorization Decolorization was due to degradation based on UV-Vis, FTIR, and GC/MS analysis Non-toxic posttreatment products for Artemia.

Electrochemical and photocatalytic properties of ZnO nanostructures deposited on nanoporous anodized aluminum oxide membrane and its application for degradation of reactive blue 19 in textile wastewater

The current study's objective was to develop a ZnO photocatalyst for the treatment of reactive blue 19 (RB19) from textile wastewater by depositing ZnO nanostructures over nanoporous anodized aluminum oxide (ZnO-AAO). The ZnO-AAO membrane was created using the atomic layer deposition (ALD) technique. SEM, XRD, and EDS morphological and structural characterizations demonstrated that ZnO nanostructures were successfully deposited on the AAO membrane. Studying the optical properties revealed that the band gap energies for ZnO, AAO, and ZnO-AAO membranes were found to be 3.19, 2.85, and 2.92 eV, respectively. This resulted in an improvement in the separation efficiency of photo-excited electrons and holes as well as an increase in the photocatalytic activity of the ZnO-AAO sample in the visible light region. Studying the electrochemical parameters revealed that ZnO-AAO had the lowest charge transfer resistance, which indicates that photoinduced electrons and holes in ZnO-AAO contacts effectively transfer charge and have slower recombination rates. According to research on photocatalytic performance, ZnO-AAO and ZnO photocatalysts required 70 and 90 min of visible light exposure to completely decolorize RB19, respectively. The photocatalytic decolorization of RB19 in an actual sample of textile wastewater showed that the dye could be effectively removed by photocatalytic means when ZnO-AAO membrane photocatalyst was present.

A novel strategy for enhancing anaerobic biodegradation of an anthraquinone dye reactive blue 19 with resuscitation-promoting factors

Anaerobic process has been widely applied as a cost-effective method for textile wastewater treatment. However, many bacteria exhibit low metabolic activity in unfavorable conditions due to the entry into a viable but non-culturable (VBNC) state. Thus, in this study, a novel method of using resuscitation-promoting factors (Rpfs), which has been proven to resuscitate and stimulate the growth of VBNC bacteria, is explored to enhance the degradation of the anthraquinone dye reactive blue 19 (RB19) in the anaerobic process. The results show that Rpfs could efficiently prompt RB19 decolorization. Compared to the conventional anaerobic condition, RB19 decolorization efficiency was increased by more than 20% with the Rpf addition. UV–visible spectral and gas chromatograph-mass spectrometry analysis indicate that the aromatic amines structures of RB19 was cleaved. More importantly, the Rpf addition appeared to stimulate and/or enrich some dye-degrading species of the family Peptostreptococcaceae, thus leading to a higher RB19 decolorization efficiency.

Effective decolorization of anthraquinone dye reactive blue 19 using immobilized Bacillus sp. JF4 isolated by resuscitation-promoting factor strategy.

Given the highly complex recalcitrant nature of synthetic dyes, biological treatment of textile wastewater using efficient bacterial species is still considered as an environmentally friendly manner. In this study, a reactive blue 19 (RB19)-degrading strain, Bacillus sp. JF4, which was isolated by resuscitation-promoting factor (Rpf) strategy, was immobilized into polyvinyl alcohol-calcium alginate-activated carbon beads (JF4-immobilized beads) for RB19 decolorization. Results suggest that the JF4-immobilized beads, which were capable of simultaneous adsorption and biodegradation, showed a high decolorization activity, while they exhibited better tolerability towards high RB19 concentrations. The JF4-immobilized beads could almost completely decolorize 100 mg/L RB19 within 10 d, while only 92.1% was decolorized by free bacteria within 12 d. Further investigation on the equilibrium and kinetics of the adsorption process suggests that the pseudo-second-order model best fit the adsorption kinetics data, and the Freundlich isotherm was the most suitable for the description of the equilibrium data. Notably, the repeated batch cycles indicated that complete decolorization of 100 mg/L RB19 by JF4-immobilized beads can be maintained for at least three cycles without much reduction in efficiency. These findings suggest that immobilizing Rpf-resuscitated strain into beads was an effective strategy for textile wastewater treatment.

Decolorization of the Reactive Blue 19 from Aqueous Solutions with the Fenton Oxidation Process and Modeling with Deep Neural Networks

The decolorization of Reactive Blue 19 (RB19) from aqueous solutions using the Fenton oxidation process was researched. The effects of different operating parameters, e.g., H2O2, Fe(II), initial dye concentration, pH, and solution temperature, on the decolorization of RB19 were investigated. Increasing, the H2O2 concentration and temperature increased the rate of the decolorization; however, increasing initial RB19 concentration reduced the decolorization. Additionally, modeling of the decolorization obtained by the Fenton oxidation process was researched based on deep neural networks (DNN) architecture providing the best performance in terms of optimum hidden layers and neuron numbers in addition to ideal activation and optimization function pairs. The performances of the models were analyzed on the training, validation, and test data. According to the experimental results, the seven hidden layers DNN model with “relu” activation function and “RMSProp” optimization function provided the best performance with root mean square error (RMSE) of 3.39 and correlation coefficient (R2) of 0.99.

Decolorization of Reactıve Blue 19 Dye By Bacillus Megaterium Isolated From Soil

The principle aim of this study was to decolorize Reactive Blue 19 dye with Bacillus megaterium(B. megaterium) and to determine the effect of some parameters such as pH, temperature, initial dye concentration, nitrogen and carbon sources
 on decolorization. With this purpose, a new isolate identified as B. megaterium by genotypic (16S rRNA sequence) characterization, was found effective on Reactive Blue 19 decolorization. Glucose (20g/L) was found as the most suitable carbon
 source for Reactive Blue 19 decolorization with a yield of 92%. When the effect of nitrogen sources on decolorization was
 investigated, the highest dye removal rate was found as 91% which was obtained in shake flask containing yeast extract (10
 g/L). In trials determining pH effect on dye removal; it was found that B. megaterium enables decolorization of Reactive Blue
 19 at neutral pHs with a high percentage of 91%. P values were calculated for all parameters and found as p<0.05. Results of
 FTIR analysis showed that decolorization of Reactive Blue 19 by B. megaterium occurred via biodegradation. When chemical
 and physical wastewater treatment methods were compared to the biological methods, usage of microbial sources such as
 B. megaterium is considered as an efficient and economical alternative.

Bioelectricity generation from the decolorization of reactive blue 19 by using microbial fuel cell

Microbial fuel cell (MFC) was compared to conventional biological techniques for decolorization of anthraquinone dye, reactive blue 19 (RB19) with simultaneous electricity generation. With 50 mg/L of RB19 in the anode chamber as a fuel, the MFC achieved 89% decolorization efficiency of RB19 within 48 h, compared with 51 and 55% decolorization efficiency achieved by aerobic and anaerobic techniques, respectively. The cyclic voltammetry results showed that RB19 could promote the electron transfer and redox reaction on the surface of anode. The RB19 decolorization process can be described by first-order kinetics, and the decolorization rate decreased with the increase of RB19 concentration. The high-throughput 16S rRNA sequencing analysis indicated significant microbial community shift in the MFC. At phylum level, the majority of sequences belong to Proteobacteria, accounting from 23 to 84% of the total reads in each bacterium community. At genus level, the MFC contained two types of microorganisms in general such as electrochemically active and decolorization bacteria. Overall, MFC is an effective method for anthraquinone dye treatment with simultaneous energy recovery. The 16S rRNA revealed that there were two major functioning microbial communities in the MFC such as electricity-producing and RB19-degrading bacteria which synergistically worked on RB19 degradation.

Development of a Novel Magnetic Reactor Based on Nanostructured Fe3O4@PAA as Heterogenous Fenton Catalyst

With the recent development of nanotechnology, magnetic nanoparticles (mNPs) have received increasing attention as potential heterogeneous Fenton catalysts in wastewater treatment applications, as an alternative to the conventional Fenton process using dissolved iron salts. Due to their superparamagnetic properties, Fe3O4 mNPs can be easily recovered and reused by applying a magnetic field. However, Fe3O4 mNPs have a marked tendency to form aggregates in water, leading to a decrease in their catalytic yield. To overcome these limitations, this work explores the catalytic activity of Fe3O4 coated with poly(acrylic acid) (Fe3O4@PAA) as stabilized Fenton heterogeneous nanocatalyst, in the degradation of C.I. Reactive Blue 19 (RB19). To maximize the catalytic potential of Fe3O4@PAA, an experimental design based on the Response Surface Methodology (RSM) has been developed to optimize the conditions of the Fenton process in terms of Fe3O4@PAA concentration (100–300 mg L−1) and H2O2 dose (100–400 mg L−1). Based on the results obtained, a novel sequential batch reactor (SBR) coupled to an external magnetic separation system has been developed, guaranteeing the complete retention of the mNPs in the system. This system allows the reuse of Fe3O4@PAA for at least 10 consecutive cycles, with a successful decolorization of RB19 after 4 h of treatment.

Application of response surface methodology in the degradation of Reactive Blue 19 using H2O2/MgO nanoparticles advanced oxidation process

The release of dye containing effluent is a great threat to the world today. The purpose of this study is to optimize the removal of Reactive Blue 19 (RB19) dye from aqueous solutions using advanced oxidation process (AOP). Magnesium oxide nanoparticles (MgO NPs) and hydrogen peroxide (H2O2) were used as the catalyst and oxidizer, respectively. Central composite design (CCD) based on response surface methodology (RSM) was applied for optimization of the AOP process. The effects of pH (3–7), molar H2O2/MgO NPs ratio (1–3), initial concentration of RB19 (20–80 mg/L), and contact time (30–90 min) were investigated on the oxidation process. The CCD was applied to determine the interactive effects of the process parameters and their optimum conditions. One-way analysis of variance (ANOVA) was applied for statistical data analysis. A quadratic model was generated by the CCD to represent the AOP on RB19 degradation. The experimental values obtained for percentage RB19 decolorization were found to be very close to the predicted response values. Based on the design, optimum conditions of pH 3, contact time of 60 min, RB19 concentration of 80 mg/L and H2O2/MgO NPs molar ratio of 3 were obtained which resulted in 93.77% RB19 removal. High value for the coefficient of determination, R2 (0.912) and adjusted R2 (0.805) showed that the removal of RB19 dye using AOP can be described by the RSM. The ANOVA results showed that the quadratic model developed from the RSM was statistically significant for RB19 decolorization. From the study, it could be concluded that the RSM can be a useful tool for optimization and moderation of the process parameters to maximize RB19 dye removal from aqueous solutions and the advanced H2O2/MgO NPs oxidation process.

ELECTROCHEMICAL OXIDATION OF SYNTHETIC ORGANIC DYES BY FERRATE (VI), USING COMMERCIAL STEEL WOOL ELECTRODES

This paper deals with the in-situ electrochemical oxidation of Reactive Black 5 (RB-5), Reactive Blue 19 (RB-19) and Allura Red AC (AR-AC), using commercial steel wool as electrodes. At the optimal conditions (18 V and NaOH 0.33M), the decolorization of RB-19 (anthraquinone-type dye) is much more rapid than those of azo dyes RB-5 and AR-AC. The reaction rates based on a first order reaction model were 0.134 min -1 for RB-19, 0.043 min -1 for RB-5 and 0.028 min -1 for AR-AC. Color removal efficiencies were higher than 95% achieved in 120 min. The analyses of spectra of the three dyes in the visible region indicate a complete cleavage of both azo and quinoid chromophores. In the case of RB-19 no new absorption peaks occurred in the UV region, showing a partial oxidation of aromatic groups without the generation of intermediates. In case of both azo-type dyes RB-5 and AR-AC, formation/accumulation of intermediates followed by their partial oxidation may have occurred. All these observations indicate that the predominant mechanism for decolorization was the oxidation of the three dyes. We conclude that that the electrochemical oxidation by ferrate (VI), under low voltages and low NaOH concentrations, using commercial steel wool as electrodes is an efficient and cost-effective alternative for the decolorization of azo and anthraquinone type dyes. For future studies a COD analysis should be made in order to correlate the decolorization and the elimination of the organic load in the dye solutions.

Decolorization of reactive blue 19 from aqueous solutions by electrocoagulation process

Decolorization of reactive blue 19 from aqueous solutions by electrocoagulation process

OPTIMIZATION OF REACTIVE BLUE 19 BIODEGRADATION BY PHANEROCHAETECHRYSOSPORIUM

Problematic dyes extensively used in different industries such as textile, paper, food, plasticsand cosmetics have undesirable environmental effects. White rot fungi demonstrating effective extracellularenzyme system, which is capable of degrading dyes and various xenobiotics. The aim of this study was tooptimize decolorization of reactive blue 19 (RB19) dye using Phanerochaetechrysosporium. A Box-Behnkendesign and Response Surface Methodology (RSM) were used to study the effect of independentvariables, namely glycerol concentration (15, 20 and 25 g/L), temperature (27, 30 and 40oC) and pH (5.5, 6.0 and 6.5) on color removal efficiency in aqueous solution. From RSM-generated model, the optimum conditions for RB19 decolorization were identified to be at temperature of 20oC, glycerol concentration of 120/L and pH: 6.5. At the optimum conditions, predicted decolorization was 98 percent. The confirmatory experiments were conducted, which confirmed the results by 99.8 percent color removal. Thus, the experimental investigation and statistical approach enabled us to improve reactive blue 19 biodegradation process by Phanerochaetechrysosporium up to 1.25 times higher than non-optimized conditions.

Decolorization of anthraquinone dye Reactive Blue 19 by the combination of persulfate and zero-valent iron

Decolorization of anthraquinone dye Reactive Blue 19 (RB19) with sulfate radicals generated in situ from persulfate and zero-valent iron (ZVI) was investigated. The effects of initial solution pH, initial concentration of RB19, ZVI and persulfate, reaction temperature and common dissolved anions were studied. 100% color removal efficiency and 54% TOC removal efficiency were achieved in 45 min with an initial RB19 concentration of 0.1 mM under typical conditions (pH 7.0, 0.8 g L(-1) ZVI, 10 mM persulfate and 30 C). The decolorization efficiency of RB19 increased with higher iron dosage, higher initial persulfate concentration, and higher reaction temperature. It is also an acid driven process. The decolorization process followed pseudo-first order kinetics and the activation energy was 98.1 kJ mol-1. RB19 decolorization was inhibited by common dissolved anions such as CL-, NO3-, H2PO4- and HCO3- since they reacted with sulfate radicals that retarded the oxidation process. The experiment demonstrated that the combination of persulfate and ZVI was a promising technology for the decolorization of dye wastewater.

Effect of a non-ionic surfactant, Merpol, on dye decolorization of Reactive blue 19 by laccase.

Abstract Laccase is a multi-copper oxidase that can decolorize textile dyes. There is increasing interest in its use to treat textile wastewaters which also contain auxiliary chemicals such as surfactants and salts. This investigation examines the effect of Merpol, a non-ionic surfactant, on the decolorization of Reactive blue 19, an anthraquinone dye, and on the oxidation of 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) by Trametes versicolor laccase. The results show that the surfactant had little effect on the enzyme or on ABTS oxidation which followed Michaelis–Menten kinetics. However, Reactive blue 19 decolorization was inhibited with increasing Merpol concentration. Spectroscopic analysis of the dye with Merpol and analysis of the kinetic data show that decolorization rates depended on an interaction between the dye and the surfactant. The proposed inhibition by a substrate depletion model in which the dye concentration decreases as a dye molecule binds to a surfactant molecule and/or is sequestered into micelles fits the data suitably and the model was validated by estimating the inhibition constant from independent saturation equilibrium binding assays. This study is the first to investigate the kinetic effect of a surfactant on the enzymatic dye decolorization and to show the depleting effect of Merpol on Reactive blue 19.

An optimization study using response surface methods on the decolorization of Reactive Blue 19 from aqueous solution by ultrasound

The decolorization of reactive dye C.I. Reactive Blue 19 from aqueous solution was studied by using ultrasound, activated carbon and combined ultrasound/activated carbon. The combined effects of independent variables, such as ultrasound power, temperature, time, activated carbon concentration, dye concentration and initial pH were investigated on the decolorization by using the central composite design. The decolorization of RB 19 was modelled statistically and optimized by means of the Matlab computer software. The decolorization were accomplished at optimum conditions by using ultrasound, activated carbon and combined ultrasound/activated carbon as 36%, 91% and 99.9%, respectively. The application of ultrasonic irradiation was found to be beneficial for decolorization of RB 19 from aqueous solution by adsorption.