PHOTOCATALYTICDEGRADATION OF RHODAMIN-B USING METAL COMPLEXES AND HYDROGEN PEROXIDE

ABSTRACT The photocatalytic degradation has been considered to be an efficient process for degradation of organic pollutants, which are present in the effluents released by industries. Thephotocatalytic bleaching was carried out on rhodamin-B (cationic dye) in the presence of iron (III) complex, hydrogen peroxide and was observed spectrophotometrically. The effect of various operating variables like pH, concentration of complex and dye, amount of HzOzand light intensity etc. was also observed on the efficiency of the reaction. A tentative mechanism has also been proposed for this photocatalytic degradation of rhodamin-B. Keywords: Photocatalytic degradation, rhodamin-B, metal complexes, hydrogen peroxide

MW assisted synthesis of some heterocyclic compounds and their Mannich bases under solvent free conditions and their biological assay

A highly efficient MW assisted synthesis of different nitrogen containing heterocyclic compounds under solvent free conditions was reported. Their aminomethylation was carried out on acidic alumina under microwave irradiation to give the corresponding Mannich bases. The method is clean, fast, facile, efficient, low cost and environmentally benign. The structure of synthesized compounds has been characterized on the basis of their elemental analysis and spectral data. These compounds were evaluated for their antimicrobial activity against bacteria and fungi

Microwave Assisted Synthesis, characterization and biological studies of isonicotinoylhydrazones and their Manganese (II) complexes

Among the most promising cleaner and energy efficient technologies, microwave-assisted technique has been popularly used for organic and inorganic synthesis. The use of microwave ovens in chemical synthesis has increasingly grown, due to its ability to dramatically reduce reaction times, improve yields, and simplified procedures. It is, therefore planned to synthesize some new Mn (II) Schiff base complexes using microwave irradiation technique. The Schiff base ligands 1-(2-furanyl) ethanone isonicotinoylhydrazone (L5H), 1-(2-thienyl) ethanone isonicotinoylhydrazone (L6H), 1-(2- pyridyl) ethanone isonicotinoylhydrazone (L7H), 1-(2-naphthyl) ethanone isonicotinoylhydrazone (L8H), were prepared by the condensation reaction of isonicotinic acid hydrazide with corresponding ethanons in 1:1 molar ratio, respectively, in ethanol under microwave exposure. The Mn (II) complexes have been prepared by mixing MnCl2.4H2O in 1:1 and 1:2 molar ratios with monofunctional bidentate ligands. The structure of the ligands and their transition metal complexes were confirmed by the elemental analysis, molecular weight determinations, IR, electronic and EPR spectral studies. On the basis of these studies it is clear that the ligands coordinated to the metal atom in a monobasic bidentate mode, by O∩N donor system. Thus a tetrahedral environment around the Mn (II) ionhas been proposed. The antimicrobial activity of Schiff base ligands and their respective Mn (II) complexes were tested against some of pathogenic bacterial and fungal strains. The results indicated that the complexes showed higher activity than the parent ligands

Dye-sensitized Photo-oxygenation of Nitrofurazone by Singlet Oxygen

Dye-sensitized photo-oxygenation of nitrofurazone by singlet oxygen has been carried out under various reaction conditions, including changes in solvents and sensitizers. The product has been isolated and characterized by elemental analysis, physical, chemical and spectral data. A suitable mechanism has been proposed for the formation of photoproduct. To confirm the participation of singlet oxygen in the reaction, singlet oxygen scavengers have been used in the photo-oxygenation reaction

Enhanced photocatalytic degradation of nigrosine dye from its aqueous solution using La2Ce2O7 nanoparticles

172-179In the present work, removal of nigrosine dye from its aqueous solution via combined photocatalysis and adsorption has been reported using ternary catalyst lanthanum cerate under visible light. The catalyst has been synthesized by citric acid assisted sol-gel method. XRD graph reveals that the average crystallite size of sample is found to be approximate 4.0 nm having cubic fluorite structure. There is 64.45% oxygen. 17.76% lanthanum and 17.79% cerium atoms present in the material, as observed by EDS result. FESEM results shows that obtained particles are in the form of rice grain shape arranged densely in homogeneous manner. TGA curve shows that there is a evaporation of moisture, nitrate and carbon. Two exothermic peaks are observed at about 170°C and 200°C in the DTA curve. The UV-Visible spectrum gives the band gap of lanthanum cerate and it is 3.0 eV. A spectrophotometer has been used to follow the photocatalytic degradation of nigrosine dye at specific intervals of time. The effect of various parameters such as pH, concentration of dye, photocatalyst dosage and light intensity has been studied on the rate of degradation. A tentative mechanism for degradation of nigrosine has been proposed involving superoxide and hydroperoxyl radicals as main oxidizing species

Photoreduction of congo red by ascorbic acid and EDTA over cadmium sulphide as photocatalyst

2266-2269The photoreduction of congo red in presence of CdS and ascorbic acid or EDTA has been carried out. The effect of different parameters like pH, light intensity, concentrations of congo red and reductants and amount or semiconductor on the rate of photocatalytic reaction has been studied. On the basis of observed data, a tentative mechanism for the photoreduction of congo red has been proposed

PHOTOCATALYTIC DEGRADATION OF RHODAMIN-B USING METAL COMPLEXES AND HYDROGEN PEROXIDE

The photocatalytic degradation has been considered to be an efficient process for degradation of organic pollutants, which are present in the effluents released by industries. The photocatalytic bleaching was carried out on rhodamin-B (cationic dye) in the presence of iron (III) complex, hydrogen peroxide and was observed spectrophotometrically. The effect of various operating variables like pH, concentration of complex and dye, amount of H2O2 and light intensity etc. was also observed on the efficiency of the reaction. A tentative mechanism has also been proposed for this photocatalytic degradation of rhodamin-B.   Keywords: Photocatalytic degradation, rhodamin-B, metal complexes, hydrogen peroxid

Photocatalytic degradation of Phenol Red using complexes of some transition metals and hydrogen peroxide

The photocatalytic degradation of Phenol Red was investigated using thiocyanate complexes of iron, copper, cobalt and hydrogen peroxide. The rate of photocatalytic degradation of the dye was followed spectrophotometrically. The effect of the variation of different parameters, such as pH, concentration of the complexes and dye, amount of H2O2 and light intensity on the rate of photocatalytic degradation was also studied. A tentative mechanism for the photocatalytic degradation of Phenol Red is proposed