Showing papers on "Brilliant green published in 2007"

Adsorption of cationic dyes on Jalshakti, super absorbent polymer and photocatalytic regeneration of the adsorbent

Abstract: This paper presents a study on the batch adsorption kinetics of seven cationic dyes, namely, Methylene Blue, Safranine T, Rhodamine B, Crystal Violet, Malachite Green, Brilliant Green, and Basic Fuchsine onto Jalshakti® (JS), a super absorbent polymer, from aqueous solution. The adsorption of dyes reaches equilibrium in 60–90 min. Equilibrium isotherms and intraparticle diffusion rate constants were measured for single component systems. It is found that uptake of dyes on JS follows the Langmuir and Freundlich isotherm models. The particle diffusion study showed that the initial boundary layer diffusion is followed by intraparticle diffusion effects. The flat and planar dye molecules are readily adsorbed as compared with the propeller shaped triphenylmethane dyes. Photocatalytic regeneration of spent JS using UV/TiO2 is more effective compared to conventional methods. Further, the regenerated JS exhibits 90% efficiency for subsequent adsorption cycle with Methylene Blue and Safranine T aqueous solutions.

Decolorization of Textile Dyes by Wet Oxidation Using Activated Carbon as Catalyst

Abstract: A commercial activated carbon, Industrial React FE01606A, without impregnation of any metal, was used as a catalyst in the wet oxidation of three dyes commonly found in textile wastewaters, Orange G, Methylene Blue, and Brilliant Green Runs were carried out in a three phase fixed-bed reactor by feeding concurrently an aqueous phase containing 1000 mg/L of the dye and an oxygen gas flow rate of 90 mL/min Temperature was set to 160 °C, and the pressure in the reactor was fixed to 16 bar The catalyst showed high catalytic activity in dye conversion and color removal The catalyst kept stable during the time tested on stream (200 h) Total decolorization is obtained at short residence times, but some refractory organic intermediates are obtained (mineralization achieved an asymptotic value about 40-60% depending on the dye) The toxicity of the inlet and outlet effluent was measured by the Microtox bioassay, and the oxidation intermediates identified and quantified explained the obtained toxicity evolution

The hydrolysis of brilliant green and some derivatives. I. A kinetic and equilibrium study of the hydrolysis of brilliant green

Abstract: The hydrolysis of Brilliant Green has been studied over the pH range 6–11. In neutral aqueous solution and in the absence of light, the system reaches equilibrium. In alkaline solution, complete conversion into the dye base occurs. Rate constants and activation parameters have been obtained for the hydrolysis and a reaction scheme is proposed.

Kinetics and mechanism of the alkaline fading of brilliant green in aqueous solutions of a double-tailed and some single-tailed cationic surfactants

Abstract: The alkaline fading of Brilliant green (a triphenylmethane dye) was studied in aqueous solutions of dodecyltrimethylammonium bromide (DTAB), didodecyldimethylammonium bromide (DDAB) and cetyltrimethylammonium bromide (CTAB) at 25 °C. The pseudo-first order rate constant variation with surfactant concentration shows a sigmoid shaped curve, which is analogous to the positive cooperativity in enzymatic reactions. The catalytic factors k Ψ /k w (the ratio of the rate constant in presence of surfactant additives to that in the pure water) of 1.8, 11.9 and 30.4 were obtained for DDAB, DTAB and CTAB respectively. The kinetic analysis shows that the bifurcated surfactant does not affect the observed rate appreciably as compared with the single-tailed surfactants. This is consistent with the length of the carbon chain being the dominant influence on the rate enhancement. The data obtained fit the Pieszkiewicz model with the value of the cooperativity index n greater than unity in all cases, but less than the number of surfactant molecules found in micelle, which indicates the presence of pre-micelle aggregates.

The use of metal phosphonates in the removal of anti infective organic molecules by adsorption process

Abstract: A novel hybrid ion exchange material of the class of metal (IV) phosphonate, zirconium - hydroxy ethylidene diphosphonate [ZrHEDP] has been synthesized by sol-gel method. The material has been characterized for elemental analysis (ICP-AES), thermal analysis (TGA, DSC), FT-IR and X-ray diffraction studies. Chemical resistivity of the material in various media - acids, bases and organic solvents has been assessed. The Na + ion-exchange capacity (IEC) of the material has been determined and effect of heating on IEC studied. The sorption behaviour of medicinal dyes Acriflavin (AF) and Brilliant Green (BG) towards ZrHEDP has been studied at 313 K, 323 K and 333 K and kinetic and thermodynamic parameters evaluated. Adsorption isotherms [Langmuir and Fruendlich], breakthrough capacity and elution behaviour of dyes have also been studied. Sorption affinity of medicinal dyes towards ZrHEDP is found to be BG > AF.

Sonochemical Degradation of Some Triphenyl Methane Dyes

Abstract: Sonochemical degradation of brilliant green and malachite green has been carried out by ultrasound (4 MHz) in an ultrasonic interferometer. The sonochemical degradation of dyes was observed by spectrophotometric method. The effect of various parameters like pH, concentration of dyes, solvent composition, temperature, nature and concentration of surfactant on the reaction rate of the sonochemical degradation was also observed. The value of energy of activation was also computed for sonochemical degradation. A tentative mechanism has been proposed.

Preparation of Nanometer TiO_2 and Its Application in Basic Brilliant Green Dye Wastewater Degradation

Abstract: TiO2 nanoparticles were prepared by Sol-Gel process and characterized by SEM and XRD. The degradation of basic brilliant green wastewater was conducted using high-pressure mercury lamp as light source and TiO2 nanoparticles as photocatalyst. The effects of the light source, the dosage of catalyst, the pH of the solution and the initial concentration of basic brilliant green on the degradation of basic brilliant green were studied. The results showed that the degradation rate of basic brilliant green could reach 93.6% when high-pressure mercury lamp was light source, the mass concentration of TiO2 was 0.4 g·L-1, the pH was 7, the mass concentration of basic brilliant green was 2 mg·L-1 and the irradiation time was 120 min.