Binary Dye Mixtures Research Articles

ОДНОЧАСНЕ СПЕКТРОФОТОМЕТРИЧНЕ ВИЗНАЧЕННЯ ХАРЧОВИХ БАРВНИКІВ У БІНАРНИХ СУМІШАХ МЕТОДОМ СТАНДАРТНИХ ДОБАВОК H-POINT

A simple, rapid and highly sensitive method for the determination of the content of synthetic food dyes in binary mixtures using the standard H-point additives has been developed. The theoretical foundations of the method are given. The following analytical wavelengths were selected to determine the yellow dye «Sunset» (E 110) and Ponceau 4R (E124) in mixtures: 446 and 521 nm for the dye E110 and 470 and 542 nm for the dye E124. In accordance with the requirements of the method, for these wavelengths, both absorbance and concentration were the same. At the same time, for the other component, the difference in absorbances at the same wavelengths was large enough and the concentration changed systematically. Simultaneous determination of dyes E124 and E110 is possible with satisfactory precision in the range of their concentrations in a mixture from1 to 30 μg/mL. The method is characterized by satisfactory precision, and the relative error does not exceed 4 % when using the SF-46 spectrophotometer. The technique has been successfully tested on artificial mixtures and commercially available carbonated beverage samples: «Mirinda», «Shake», «InStyle», «Fruits Multivitamin».

Magnetic BiFeO3 decorated UiO-66 as a p–n heterojunction photocatalyst for simultaneous degradation of a binary mixture of anionic and cationic dyes

Magnetic UiO-66/BiFeO3 composite for simultaneous photodegradation of a binary mixture of anionic and cationic dyes.

Spectral deconvolution associated to the Gaussian fit as a tool for the optimization of photovoltaic electrocoagulation applied in the treatment of textile dyes

The objective of this study was to investigate the color removal in a binary mixture of azo dyes from the photovoltaic electrocoagulation (EC) technique, using spectral deconvolution and the Gaussian fit for qualitative and quantitative determination of the physical color parameter. Initially, a conventional energy source was used to feed the EC reactor and the experimental design was conducted according to the Rotational Central Compound Design (RCCD). The spectral deconvolution method associated to the Gaussian fit aided in the description of the composition of the sample matrix, In the first step, through the Analysis of Variance, the RCCD and the three-dimensional surface response graphs, the optimized operating conditions were identified, which corresponded to 1320 A m−2 with an reaction time of 16.6 min, and an expected removal of 98.40% for Scarlet Red (SR) dye and 1160 A m−2 with a run time of 15.7 min and 97.9% removal for Turquoise Blue (TB) dye. Using the photovoltaic module as the power source of the EC reactor, a maximum removal of 97 ± 0.43% for TB dye and 98% ± 0.81 for SR was obtained. The results encourage the applicability of photovoltaic module-fed EC technology as a promising alternative for the treatment of effluents containing textile dyes, as well as the use of the spectral deconvolution method associated with the Gaussian fit, for the reliability and precision of the results.

Selective Adsorption Capacity of Grape Marc Hydrogel for Adsorption of Binary Mixtures of Dyes

In this work, an aqueous solution containing industrial dyes consisting of methylene blue (MB), and methyl red (MR) was treated with bio-oxidize grape marc entrapped or not in calcium alginate hydrogels. Experiments were carried out in batch, a room temperature using different concentration of adsorbents and dyes. When dyes were evaluated separately, non-immobilized grape marc hydrogel was unable to remove any MR, whereas when the bioadsorbent was immobilized in calcium alginate beads the removal of MR was around 88%. Contrarily, 98% of MB was removed with both, non-entrapped or entrapped grape marc. Regarding binary mixtures, it was observed that the adsorption of MR was not affected by the presence of MB, whereas the adsorption of MB decreased in high extend on non-entrapped grape marc when MR was present. Adsorption conditions were optimized for binary mixtures using a Box-Behnken factorial design, obtaining theoretical equations that allowed to calculate the removal percentage and capacity of calcium alginate-grape marc hydrogel depending on the concentration of dyes (40–100 mg/L), ratio between bioadsorbent and water stream (0.6–1.2) and adsorption time (10–60 min). The equations obtained revealed that grape marc hydrogel is able to remove 100.0–93.3% of MB and 78.72–57.80% of MR in 10 min in the range of dye and bioadsorbent stablished in the experimental design, being the extraction time the less significant variable. Additionally, the kinetic study showed that pseudo-second-order was the model that better explained the bioadsorption process for both dyes in binary mixtures onto grape marc hydrogel.

Evaluation of several white-rot fungi for the decolorization of a binary mixture of anionic dyes and characterization of the residual biomass as potential organic soil amendment

Industrial pollution is a great concern for modern society and developing cyclic processes is one of the major challenges. As far as we know, this work is the first to report the use of multiple white-rot fungi species for degrading a binary mixture of anionic dyes under solid state fermentation (SSF) conditions and a further physicochemical characterization of the residual biomass. First, eight white-rot fungi decolorized the dye mixture of brilliant blue FCF and allura red AC adsorbed onto corncob, reaching decolorizations between 11.47% and 87.64%. Then, I. lacteus, B. adusta and T. versicolor, based on the decolorization yield, were selected to evaluate the effect of carbon:nitrogen ratio, moisture content and inoculum quantity on the decolorization percentage. The factorial designs showed that C:N ratio had a negative effect while moisture and inoculum quantity a positive effect. In terms of the kinetics, the three white-rot fungi achieved their maximum decolorization level, around 80.11–86.04%, after 10-12 days. I. lacteus exhibited the highest decolorization percentage, even though only the enzyme manganese peroxidase was detected, with a maximum activity of 6.62 U gds−1 at day 14. Besides, T. versicolor was the only species with laccase activity, with a maximum of 15.94 U gds−1 at day 6 of fermentation. The physicochemical characterization of the biomass allowed to conclude that these aggregates represent a potential organic amendment, as for their significant oxidizable organic carbon (more than 9.5% on wet basis) and essential nutrients content, as well as for their low ash content (less than 1% on wet basis). Finally, for outlining an efficient bioremediation cycle, a cheap and effective methodology for drying the biomass at the end of the SSF process is required.

Biosorption of Reactive Black 5 in Binary Dye Mixture onto Sawdust of Parkia biglobosa

Biosorption of Reactive Black 5 in Binary Dye Mixture onto Sawdust of <i>Parkia biglobosa</i>

Selective removal of anionic dyes with exceptionally high adsorption capacity and removal of dichromate (Cr2O72-) anion using Ni-Co-S/CTAB nanocomposites and its adsorption mechanism

An adsorbent Ni-Co-S/CTAB nanocomposites have been synthesized at low temperature in aqueous medium using nickel acetate, cobalt acetate, thioacetamide and hexadecyltrimethyl ammonium bromide (CTAB) as reagents. The nanocomposites exhibited exceptionally high adsorption capacity towards anionic adsorbates with high selectivity. The maximum adsorption capacity of nanocomposites were 1995.02 mg g−1 for Congo red (CR), 2223.15 mg g−1 for Methyl orange (MO) anionic dyes and 790.69 mg g−1 for Cr2O72- metal anion. They exhibit negligible adsorption ability towards cationic dyes 2.33 mg g−1 for MB and 42.05 mg g−1 for RhB. The nanocomposite is able to adsorb anionic dyes from a binary mixture of cationic and anionic dyes with high separation factor. It also shows good results with synthetic effluents. The removal of adsorbates followed modified Zhu and Gu isotherm model. FTIR and Zeta-potential measurement confirmed that electrostatic interactions are predominating factor for the adsorption of anionic adsorbates followed by hydrophobic interactions between adsorbates. Moreover, ethanol is used to regenerate the adsorbent and reused up to five times with good adsorption capacities. Thus, the nanocomposite can be used as an efficient adsorbent for the removal and seperation of anionic adsorbates from binary mixtures as well as synthetic effluents.

Super Dye Adsorption Capability of Natural Superfine Down Particles for Organic Contaminant from Binary Dye Mixture

Super Dye Adsorption Capability of Natural Superfine Down Particles for Organic Contaminant from Binary Dye Mixture

Comparative studies of pure cultures and a consortium of white-rot fungi to degrade a binary mixture of dyes by solid-state fermentation and performance at different scales

White-rot fungi have been widely used in pure culture and consortia for treating recalcitrant compounds, such as synthetic dyes, since they are able to cleave and mineralize lignin using ligninolytic enzymes. Moreover, solid-state fermentation stands out in the treatment of dyes due to its low environmental impact. In this study we evaluated the degradation of allura red and tartrazine adsorbed onto corncob by either pure cultures or binary consortia of Trametes versicolor and Pleurotus pulmonarius. We performed a comparative study in terms of culture conditions optimization, degradation, activity of ligninolytic enzymes kinetics, and cytotoxicity assessment to unravel the differences between using individual cultures or consortium of white-rot fungi. 94% of the dye mixture was degraded in pure cultures, but only 64.3% was broken-down by the consortium. Enzymatic activity and degradation kinetics showed that T. versicolor maximum laccase activity corresponded to the plateau phase of degradation whilst for P. pulmonarius and consortium no match between both profiles was found. Also, T. versicolor extracts were not cytotoxic to CHO–K1 cell line. The process was therefore magnified using T. versicolor in pure culture. The degradation efficiency was maintained in all the sizes, allowing an increase of 20 times the amount of treated dyes.

Tunable single-mode cw energy-transfer dye laser directly optically pumped by a diode laser

Within this work a tunable single-mode continuous wave energy transfer dye laser operation in green-yellow spectral region was achieved under direct optical pumping by an economy-class diode laser at λ = 445 nm. The laser is operated on a binary dye mixture: Coumarin 498 (donor) and Pyrromethene 556 (acceptor); the latter exhibits only negligible absorption at the pump wavelength, and thus its lasing is almost exclusively due to the excitation energy transfer. This binary energy transfer dye mixture was studied for the first time. Basic lasing properties at various acceptor concentrations were examined; donor concentration was fixed at the value optimum for its lasing under the optical pumping conditions applied. For the final acceptor concentration the optimum output coupling was determined for selected wavelengths from the measurements of the output power in variable output coupling scheme. Single-mode operation sufficiently stable for high-resolution spectroscopic applications was also achieved and tested. Further investigations of the energy transfer mechanisms and efficiency in the binary dye mixture applied are in progress and will be reported separately.

Effect of copper and different carbon and nitrogen sources on the decolorization of an industrial dye mixture under solid-state fermentation

Abstract The treatment of colored effluents has been addressed using different methodologies, such as the coupling of adsorption to solid-state fermentation (SSF). This work shows for the first time the use of an agricultural by-product (corncob) as the adsorbent for the removal of the binary mixture of dyes, brilliant blue and allura red, and their subsequent decolorization by white-rot fungi. Pleurotus ostreatus, Trametes versicolor and their consortium were the selected fungal species for carrying out the second step of this bioprocess. A 23 full factorial design was adopted, obtaining a maximum decolorization of 90.8 ± 4.1% with T. versicolor at a 20:1 carbon:nitrogen ratio, 80% moisture and the absence of inducer. Moreover, the effect of different carbon and nitrogen sources was evaluated; yeast extract was discovered to be the most efficient nitrogen source, while the supplement of a carbon source was unnecessary to reach high levels of decolorization. Regarding the influence of the inducer, it was found that although copper addition favored enzyme levels of laccase (Lac), no positive effect was observed in either the decolorization rate of the dye mixture or the manganese peroxidase (MnP) activity, and a maximum of 19.8 ± 2.1 U Lac gds−1 and 5.4 ± 1.3 U MnP gds−1 was obtained. These results suggest that the coupled adsorption-SSF methodology using corncob and white-rot fungi represents a promising strategy for the treatment of effluents polluted with dye mixtures.

Clusters of superparamagnetic iron oxide nanoparticles capped with palm shell extract and modified with chitosan: Catalytic applications for degradation of cationic and anionic dyes and their binary mixtures

Heterogeneous regenerative iron oxide nanocatalyst capped with palm shell extract(IO) and IO modified with chitosan has been developed by simple coprecipitation of ferrous and ferric salts for degradation of single and binary mixture of dyes in aqueous phase. The iron oxide nanoparticles were characterized using IR, UV, TEM, XRD, Raman, VSM and Mossbauer techniques. The obtained results suggest the presence of Fe3O4, γ-Fe2O3 and α-Fe2O3 in IO and CIO though to different extents. The degradation process was carried out at room temperature and at near neutral pH which led to complete degradation and multicyclic use of the nanocatalyst for environmental applications without loss in efficiency. CIO was observed to be more efficient as compared to IO during catalytic degradation of binary mixture of dyes.

Energy transfer and photostability of Rh-6G and Rh-B doped in polyacrylamide polymer

In this study, the polyacrylamide gel was chosen as a host material and the two rhodamine dyes: rhodamine 6 G (Rh-6 G) and rhodamine B (Rh-B) were chosen as guest molecules in order to prepare a novel guest–host systems (dye-loaded polyacrylamide gel) with promising optical properties. For the first time different concentration of binary mixture of dyes (Rh-6 G/Rh-B) doped polyacrylamide gel were prepared, the optical absorption and amplified spontaneous emission (ASE) of the dye doped polyacrylamide, which is pumped by the second harmonic (532 nm) of Nd-YAG laser, were measured. Energy transfer from Rh-6 G to Rh-B has been studied. The critical transfer distance R0 has large value (12.5 A0). The gain and amplified spontaneous emission (ASE) efficiency for Rh-6 G and Rh-B doped polyacrylamide were measured under the same experimental condition. The optical gain was 4.5 cm−1 for Rh-6 G and 2.5 cm−1 for Rh-B and the amplified spontaneous emission (ASE) efficiency was 30% for Rh-6 G and 26% for Rh-B. The photostability for fresh samples of (Rh-6 G and Rh-B) and after 24 hours from the first use were studied. A self-healing phenomenon for the samples were observed.

Effect of combined laser dyes on the efficiency of cholesteric liquid crystal lasers

A high efficiency band-edge cholesteric liquid crystal (CLC) laser comprising an optimal binary-dye mixture (OBD) with 62 wt% DCM and 38 wt% PM597 as the active medium is scrutinized. The measurements indicate that both the fluorescence spectrum width and the order parameter of OBD in the host of nematic liquid crystal (BL009) enhance compared with those for each individual dye. Furthermore, at the fluorescence peak, the optical efficiency of the PM597-doped CLC laser is ~ 1.5× higher than that of DCM, and the laser emission energy for OBD-doped CLC between the wavelengths 595 nm and 613 nm is even higher than that of PM597-doped CLC, so that at the maximum fluorescence of OBD, lambda approx 605;{text{nm}}, the improvement is over 20%.

Degradation of a synthetic binary dye mixture using reactive adsorption: Experimental and modeling studies

Simultaneous reactive adsorption of Methylene Blue (MB) and Safranin O (SO) was carried out from a binary aqueous mixture using Fe-GAC/H2O2. Maximum simultaneous removal was found to be 96.2% and 90.2% for MB and SO respectively after 7 h of reactive adsorption using 0.5 g/L Fe-GAC and 20 mM H2O2 optimized doses. Degradation activities of the dyes were accelerated by increasing temperature from 15 to 35 °C. Apparent kinetic reaction rate constant was also increased with increasing temperature and consequently, activation energies of the degradation of individual dyes present in mixture were estimated and found to be 28.59 kJ mol−1 and 32.53 kJ mol−1 for MB and SO respectively. Thermodynamic parameters for MB and SO activation were assessed for the degradation process. Thermodynamic study and ESI-MS analyses revealed that molecule of SO is more difficult to remove than MB. Degradation pathways for MB and SO have been proposed which indicated that the dyes were degraded via demethylation and hydroxylation processes. For pure adsorption of MB and SO, intraparticle diffusion model and extended Freundlich model were found suitable for kinetic and thermodynamic studies, respectively. A film solid pore diffusion model was developed and used to predict the surface mass transfer coefficients (kL), diffusion coefficients (D) for adsorption and reactive adsorption, along with surface reaction rate constants (kR) for reactive adsorption for a binary dye system containing MB and SO. Results from model and experiments were analogous and removal of MB was found to be faster than SO.

Chitosan-Guar gum blend silver nanoparticle bionanocomposite with potential for catalytic degradation of dyes and catalytic reduction of nitrophenol

Chitosan-Guar gum blend Silver Nanoparticle bionanocomposite (CGS) was synthesized by incorporating palm shell extract capped nano silver particles during the formation of blend. The nanocomposite was characterized with IR, TEM, XRD and Raman spectroscopic techniques. The catalyst was further investigated for degradation of single and binary mixture of dyes as well as for reduction of nitrophenol. Further the prepared catalytic composite CG could be conveniently separated from the aqueous solution after the reaction andcould be reused upto three cycles without loss in activity.

Local environment of organic dyes in an ionic liquid-water mixture: FCS and MD simulation.

The composition dependent local environment of three organic dyes in binary mixtures of a room temperature ionic liquid (1-methyl-3-pentylimidazolium bromide, [pmim][Br]) and water is studied by fluorescence correlation spectroscopy (FCS) and molecular dynamics (MD) simulations. We used three dyes-neutral coumarin 480 (C480), anionic coumarin 343 (C343), and highly hydrophobic 4-(dicyanomethylene)-2-methyl-6-(p-dimethyl-aminostyryl)-4H-pyran (DCM)-to probe different environments in the binary mixtures. The heterogeneity of the [pmim][Br]-water mixture leads to multiple values (i.e., distribution) of diffusion coefficients (Dt). In these binary mixtures, the effective viscosity (ηeff, obtained from FCS) and the local concentration of the [pmim][Br] around the three dyes (revealed by MD simulations) are found to be quite different than that in bulk. The viscosity experienced by the C480 and C343 dyes is almost twice as large as that experienced by DCM dye. Through rigorous MD simulation, we show that in the vicinity of the less hydrophobic coumarin dyes (C480 and C343) compared to DCM dye, the local concentration of the [pmim][Br] is ∼3-7 times larger than that in bulk. In the case of the most hydrophobic dye, DCM, the local concentration of [pmim][Br] is almost similar to bulk-like. Further analysis reveals the formation of hydrogen bond between the imidazolium ring of [pmim][Br] and the carbonyl oxygen atom of the coumarin dyes (C-H[pmim][Br]⋯O=CDye). Finally, computer simulation indicates a slow component of solvation dynamics in the [pmim][Br]-water mixture in the time scale of ∼100-200 ps, which is similar to the experimental observation.

High Performance Removal of Anionic and Cationic Dye Pollutants with Co3O4 Modified Nanoclinoptilolite: Kinetics and Adsorption Equilibrium Studies

In this paper Co3O4 doped nanoclinoptilolite was synthesized and characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR), field emission scanning electron microscopy (FESEM) and energy-dispersive X-ray spectroscopy (EDX) techniques. The adsorption efficiency for removing of methylene blue was about 95% in 10 min. The effect of some factors such as adsorbent dose, concentration of analyte and pH was investigated for enhancing the removing efficiency. Moreover Freundlich and Langmuir patterns were plotted for this new nanocomposite. Maximum of adsorption capacity was obtained from slope of Langmuir and was about 25 mg/g. The kinetic study for methylene blue shows a second order kinetic with rate constant about 0.02 g/mg/min. The prepared nanocomposite was successfully applied for removing some color compounds such as methylene blue, methyl green, and methyl red and also binary dye mixtures.

Compatibility of Natural Dyes on Aluminum Pre-Mordanted Woolen Yarns by Determination of Diffusion Coefficient

In the present research, a method of assessing relative compatibility rating of single and binary mixtures of walnut green shell, cochineal, and weld natural dyes on aluminum pre-mordanted woolen yarns was proposed, where a proportion of the calculated diffusion coefficients of dyes was postulated. To calculate the diffusion coefficient values, the uptake behavior of dyes was derived as the K/S and the exhaustion curves by dyeing the woolen yarn samples with the individual dye as well as with the mixtures of dyes obtained from practical conditions of dyeing. A typical method was employed to dye the samples at two temperatures of 80 and 95 oC. The method proposed for determination of the compatibility of dyes was more verified at higher temperature, that is, 95 oC, against a conventional method of solution analysis. The results of compatibility showed that the selected binary mixtures of cochineal-weld have an excellent compatibility. The other mixtures, that is, walnut green shell-cochineal and walnut green shell-weld showed weak-moderate and very weak compatibility, respectively.

Simultaneous determination of Brilliant Green and Crystal Violet dyes in fish and water samples with dispersive liquid-liquid micro-extraction using ionic liquid followed by zero crossing first derivative spectrophotometric analysis method

In this study, dispersive liquid-liquid micro-extraction using ionic liquid (IL-DLLME) combined with zero crossing first derivative spectrophotometric method was applied to quantitative determination of triphenylmethane dyes in binary mixtures. The 1-methyl-3-octylimidazolium hexafluorophosphate [OMIM][PF6] ionic liquid was used to extract Brilliant Green (BG) and Crystal Violet(CV) dyes from aqueous solutions. The amplitude of the zero crossing first derivative spectra at 670 nm and 532 nm were selected for the determination of BG and CV, respectively. Significant factors influencing the extraction of BG and CV such as sample pH, kind of extraction solvent, amount of extractant, extraction and centrifuging times and ionic strength were investigated. Under the optimal conditions, the calibration curves for the simultaneous determination of both dyes were found to be linear in the range of 10–500 μg L−1 with detection limits (LODs) of 2.7 μg L−1 and 1.4 μg L−1 for BG and CV, respectively. The relative standard deviation (RSD%) for five replicate simultaneous determinations of BG and CV were 4.7% and 1.7%, respectively. Extraction efficiencies of the BG and CV dyes in the presence of interfering ions were also investigated. Sample preparation based on the quick, easy, cheap, effective, rugged and safe (QuEChERS) extraction combined with the IL-DLLME method and zero crossing first derivative spectrophotometric detection was applied for the simultaneous analysis of BG and CV in fish and water samples with quantitative recoveries.