Showing papers on "Brilliant green published in 2012"

Adsorption studies of cationic dyes onto Ashoka (Saraca asoca) leaf powder

Abstract: In present study, batch adsorption experiments were carried out using ashoka leaf powder (ALP), a low cost, locally available biomaterial as an adsorbent for the removal of cationic dyes such as methylene blue, malachite green, rhodamine B and brilliant green from aqueous solution. The ALP was characterized by Fourier transform infrared (FTIR) spectroscopy and scanning electron microscope (SEM). Effect of various physico-chemical parameters such as pH, ionic strength, adsorbent dose, contact time, initial dye concentration and temperature were investigated and optimal experimental conditions were ascertained. Available models like Lagergren's pseudo-first order kinetics, Ho's pseudo-second order kinetics and intraparticle diffusion were used to evaluate the kinetics and the mechanism of the adsorption. The Langmuir, Freundlich, Temkin and Scatchard isotherm models were tested to represent the equilibrium data and the constants of the isotherms were determined by using the experimental data. Thermodynamic parameters such as change in Gibb's free energy (Δ G °), change in enthalpy (Δ H °) and change in entropy (Δ S °) were calculated to predict the nature of adsorption process.

Biological Removal of Azo and Triphenylmethane Dyes and Toxicity of Process By-Products

Abstract: Increasing environmental pollution is connected with broad applications of dyes and imperfection of dyeing technology. Decolourization of triphenylmethane brilliant green and disazo Evans blue by bacterial and fungal strains and toxicity (phyto- and zootoxicity) of degradation by-products were investigated. Influence of incubation method on dyes removal was evaluated (static, semi-static, shaken). Dead biomass was used for sorption estimation. Toxicity of treated dyes was measured to estimate possible influence on aquatic ecosystems. The zootoxicity test was done with Daphnia magna and phytotoxicity with Lemna minor. Samples were classified according to ACE 89/BE 2/D3 Final Report Commission EC. The best results of removal for all tested strains were reached in shaken samples. In opposite to fungi, bacterial strains decolourized brilliant green more effectively than Evans blue. The most effective bacterial strain was Erwinia spp. (s12) and fungal strains were Polyporus picipes (RWP17) and Pleurotus ostreatus (BWPH and MB). Decolourization of brilliant green was connected with decrease of zootoxicity (D. magna) and phytotoxicity (L. minor). Removal of Evans blue was connected with no changes in zootoxicity and decrease of phytotoxicity in most of samples.

Decolorization of Azo, Triphenylmethane and Anthraquinone Dyes by Laccase of a Newly Isolated Armillaria sp. F022

Abstract: A newly isolated white-rot fungus, Armillaria sp. strain F022, was isolated from the decayed wood in a tropical rain forest. Strain F022 was capable of decolorizing a variety of synthetic dyes, including azo, triphenylmethane, and anthraquinone dyes, with an optimal efficiency of decolorization obtained when dyes added after 96 h of culture, with the exception of Brilliant Green. All of the tested dyes were decolorized by the purified laccase in the absence of any redox mediators, but only a few were completely removed, while others were not completely removed even when decolorization time was increased. The laccase, with possible contributions from unknown enzymes, played a role in the decolorization process carried out by Armillaria sp. F022 cultures, and this biosorption contributed a negligible part to the decolorization by cultures. The effect of dye to fungal growth was also investigated. When dyes were added at 0 h of culture, the maximum dry mycelium weight (DMW) values in the medium containing Brilliant Green were 1/6 of that achieved by the control group. For other dyes, the DMW was similar with control. The toxic tolerance of dye for the cell beads was excellent at least up to a concentration of 500 mg/l. The optimum conditions for decolorization of three synthetic dyes are at pH 4 and 40°C.

Dye-Sensitized Photocathodes: Efficient Light-Stimulated Hole Injection into p-GaP Under Depletion Conditions

Abstract: The steady-state photoelectrochemical responses of p-GaP photoelectrodes immersed in aqueous electrolytes and sensitized separately by six triphenylmethane dyes (rose bengal, rhodamine B, crystal violet, ethyl violet, fast green fcf, and brilliant green) have been analyzed. Impedance measurements indicated that these p-GaP(100) photoelectrodes operated under depletion conditions with an electric field of ∼8.5 × 105 V cm–1 at the p-GaP/solution interface. The set of collected wavelength-dependent quantum yield responses were consistent with sensitization occurring specifically from adsorbed triphenylmethane dyes. At high concentrations of dissolved dye, the measured steady-state photocurrent–potential responses collected at sub-bandgap wavelengths suggested unexpectedly high (>0.1) net internal quantum yields for sensitized hole injection. Separate measurements performed with rose bengal adsorbed on p-GaP surfaces pretreated with (NH4)2S verified efficient sensitized hole injection. A modified version of w...

Determination of equilibrium, kinetic and thermodynamic parameters for the adsorption of Brilliant Green dye from aqueous solutions onto eggshell powder

Abstract: The removal of the Brilliant Green (BG) dye using hen eggshell powder (abundantly available and a total waste material) has been explored. Adsorption studies for the dye removal by eggshell powder has been carried out under varying experimental conditions of adsorbent dose, temperature, contact time, initial dye concentration and pH. The equilibrium data has been studied using the Langmuir isotherm equation. Monolayer adsorption capacity of hen eggshell powder for BG dye is found to be 44.7 mg/g, 34.23 mg/g and 30.23 mg/g at temperatures 303, 313 and 323 K respectively. The kinetic study on BG suggests that the adsorption follows the pseudo-second order kinetics. Adsorption follows both surface adsorption and intra-particle diffusion mechanisms. The Arrhenius energy of activation observed from the experimental data is found to be -15.88 kJ/mol which suggests that the energy barriers are absent in the adsorption process and the reaction is exothermic. The thermodynamic study on BG reveals that the reaction is spontaneous, exothermic and proceeds with decreased randomness at the solid-solution interface as the entropy change (-19.08 J/mol/K) is negative.

Adsorption of Basic Dyes from Aqueous Solutions by Depolymerization Products of Post-Consumer PET Bottles

Abstract: The purpose of this work is the removal of basic dyes (Safranine T and Brilliant Green) from aqueous media by depolymerization products (DP) obtained from aminoglycolysis of waste poly(ethylene terephthalate) (PET). The surface morphology and physical properties of depolymerization product were also determined. Adsorption behaviors (adsorption capacities, adsorption kinetics and adsorption isotherms) of these samples were realized at room temperature. Then, the amounts of residual dye concentrations were measured using Visible Spectrophotometer at 530 and 618 nm for Safranine T (ST) and Brilliant Green (BG), respectively. All adsorption experiments were carried out for different depolymerization products (DP1, DP2, DP3, and DP4). Adsorption capacities of depolymerization products for both of dyes decrease with following order: DP2 > DP4 > DP1 > DP3. The maximum adsorption capacities for ST and BG onto DP2 sample were found to be 29 and 33 mg g−1, respectively. In addition, the adsorption kinetic results show that the pseudo-second-order kinetic model is more suitable than pseudo-first-order model for the adsorption of basic dyes onto DP samples. Adsorption data were evaluated using Langmuir and Freundlich adsorption isotherm models. The results revealed that the adsorption of basic dyes onto DP sample fit very well Langmuir isotherm model. In conclusion, the depolymerization products of post-consumer PET bottles can be used as low cost adsorbent for the removal of basic dyes from wastewaters.

Responses of surface modeling and optimization of Brilliant Green adsorption by adsorbent prepared from Citrus limetta peel

Abstract: An adsorbent prepared from Citrus limetta peel was used to study its sorption potential on removing Brilliant Green dye The initial dye concentration and sorbent dosages were varied between 10–100 mg/L and 05–50 g/L, respectively The influence of parameters like pH, temperature, initial concentration, and adsorbent dosage on dye adsorption was also studied A maximum dye removal of 95% was achieved with an initial concentration of 10 mg/L The percentage removal was mathematically described as a function of experimental parameters and modeled through response surface methodology The results show that the responses on adsorption of dyes were significantly affected by the synergistic effect of linear term of time and dosage and the quadratic term of temperature and time A 24 full factorial design of experiments was adopted and statistical analysis was performed in the form of ANOVA and student “t” test, which gave good interpretation in terms of interaction of experimental parameters

Surface optical sensitization of a thin polycrystalline silver iodide film by brilliant green molecules

Abstract: The effect of the surface optical sensitization (SOS) of silver iodide in a multilayer structure by trace amounts of gaseous molecules of brilliant green dye is demonstrated. Using the surface plasmon resonance excitation, it is shown that the SOS causes changes in the surface layer parameters and can be used to develop highly sensitive and selective gas sensors.

Kinetics of Organic Dyes Degradation in Water Using Vacuum Ultra Violet Radiation

Abstract: In this study vacuum ultraviolet (VUV) radiation (185 nm wave length) was used in the presence of atmospheric oxygen as an advanced oxidation technique. Six organic dyes were examined as model pollutants ( methyl violet , methyl blue, brilliant green , malachite-green, Remazole blue B and picric acid ). Picric acid as the most persistent one was selected for more detailed kinetic investigations. The influence of each of the related main parameters was studied, Radiation time, salinity, pH, temperature and radiation intensity. Kinetics of the oxidation reaction was studied. COD was also followed up. It follows from the results that vacuum-UV radiation of 185 nm in the presence of atmospheric oxygen is an efficient method for the oxidation process. Four of sex examined dyes were degraded in different rates according to persistency of each pollutant dye. The reaction rates were in the order of: ( methyl violet > methyl blue >brilliant green > remazole > malachite green> picric acid) . In the case of picric acid; the reaction was promoted by rising the temperature, raising or lowering pH above and below pH 7.0, increasing radiation dosage. The rate was inhibited by increasing salinity and buffering. The present technique was found promising in the elimination of the persistent organic pollutants out of the treated water.

Adsorptive removal brilliant green onto carbonised aegle

Abstract: A laboratory prepared granular adsorbent was used to remove dye, brilliant green (BG) from aqueous solution. The Taguchi method was applied as an experimental design to establish the optimum conditions for the removal of brilliant green in batch experiments. The orthogonal array L25 and the larger the better response category were selected to determine the optimum removal conditions. Keywords—Aegle marmelos, Brilliant green, Taguchi, Orthogonal array.

Fluorine-18 labeled hydrogen ion probes

Abstract: Fluorine-containing molecules include fluorine-18 labeled hydrogen ion indicator molecules and methods of making and using the same. Fluorine atoms incorporated into the indicator molecules provides novel structural modifications to the precursor molecules, shifting the absorbance maxima relative to their non-fluorinated precursor / cogeners. These molecules are useful for non-invasive in vivo measurement of blood volume, blood flow and pH in biological objects. Compounds are functionalized by a radioisotopically enriched fluorine-18 label and indicator molecule with structure derived from triarylmethane derived indicators, such as phenol red, cresol red, cresol purple, thymol blue, bromophenol red, naphthol blue, phenolphthalein, cresolphthalein, thymolphthalein, naphtholphthalein, gentian violet (methyl violet 10B), methyl violet 2B, methyl violet 6B, leucomalachite green (malachite green), brilliant green, pararosaniline, fuchsines, or salts thereof. During its radioactive decay, fluorine-18 produces high-energy positrons, which can be detected by positron emission tomography (PET) or single photon emission computer tomography (SPECT).