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G Cerisola - One of the best experts on this subject based on the ideXlab platform.

  • electrochemical degradation of Methyl Red using bdd and pbo2 anodes
    Industrial & Engineering Chemistry Research, 2008
    Co-Authors: Marco Panizza, G Cerisola
    Abstract:

    The electrocatalytic properties of lead dioxide (PbO2) and boron-doped diamond (BDD) anodes were compaRed for the electrochemical incineration of Methyl Red, an azo dye, using an electrolytic flow cell with parallel-plate electrodes. The effects of several operating parameters such as current density, hydrodynamic conditions, and pH on the degradation rate and current efficiency were determined. The experimental data indicate that, on PbO2 and BDD anodes, Methyl Red oxidation takes place by reaction with hydroxyl radicals electrogenerated from water discharge. The electro-oxidation of Methyl Red was found to behave as a mass-transfer-controlled process, so that the removal rate and current efficiency were enhanced by high flow rates and independent of the pH in the range of 3.0−7.0. It was also observed that the Methyl Red decay reaction followed pseudo-first-order kinetics with a rate constant that increased slightly with applied current at the PbO2 anode but was essentially independent of current at the...

  • electrocatalytic materials for the electrochemical oxidation of synthetic dyes
    Applied Catalysis B-environmental, 2007
    Co-Authors: Marco Panizza, G Cerisola
    Abstract:

    Abstract The electrocatalytic properties of Ti–Ru–Sn ternary oxide, platinum, lead dioxide and boron-doped diamond anodes for the oxidation of Methyl Red have been compaRed by potentiodynamic measurements and bulk electrolysis. The results of the cyclic voltammetries have shown that in the potential region of supporting electrolyte stability polymeric materials, which result in electrode deactivation, are formed on the electrode surfaces. While Ti–Ru–Sn ternary oxide and platinum cannot restore their initial activity by polarization, lead dioxide and boron-doped diamond anodes can be reactivated by electrolysis in the potential region of electrolyte decomposition due to the electrogeneration of hydroxyl radicals. The bulk electrolysis showed that the complete COD and colour removal were only achieved using lead dioxide and boron-doped diamond while Ti–Ru–Sn ternary oxide and platinum only permitted a partial oxidation of Methyl Red.

Angela Agostiano - One of the best experts on this subject based on the ideXlab platform.

  • photocatalytic degradation of Methyl Red by tio2 comparison of the efficiency of immobilized nanoparticles versus conventional suspended catalyst
    Journal of Hazardous Materials, 2007
    Co-Authors: Giuseppe Mascolo, Roberto Comparelli, M L Curri, G Lovecchio, A Lopez, Angela Agostiano
    Abstract:

    Abstract The photocatalytic efficiency of supported TiO 2 nanoparticles (mean size 6 nm), immobilized onto the inner walls of a cylindrical glass photoreactor was compaRed versus the performance of conventional TiO 2 Degussa P25 catalyst. For this purpose the degradation of Methyl Red dye was used as evaluation test. The obtained results showed that the TiO 2 Degussa P25 catalyst is more efficient than the supported nanoparticles. The poorer performance of the nanosized catalyst can be ascribed to the fact that the immobilization procedure turns out, in spite of the extremely high surface to volume ratio, in an overall Reduction of active surface area available for target molecule adsorption, due to the low porosity of the supported catalyst layer. The kinetics of the investigated processes were monitoRed and a study on the reaction products and intermediates was carried out in order to evaluate possible difference in the reaction pathway in presence of immobilized nanoparticles versus suspended catalyst. The results demonstrate that the mechanisms of parent dye degradation in presence of supported TiO 2 nanoparticles are the same as those occurring in presence of TiO 2 Degussa P25 catalyst. The present work describe the results obtained on the feasibility of scaling up the colloidal nanocrystal-based photocatalysis experiment: the comparison with a well standardized degradation method performed with a known material can allow a realistic evaluation of the advantages and the limits of the investigated nanoparticle towards the ultimate technology transfer.

  • colloidal oxide nanoparticles for the photocatalytic degradation of organic dye
    Materials Science and Engineering: C, 2003
    Co-Authors: Maria Lucia Curri, Giuseppe Mascolo, Roberto Comparelli, Pantaleo Davide Cozzoli, Angela Agostiano
    Abstract:

    Abstract In this work, easily processable and highly crystalline ZnO and TiO2 nanoparticles, with a narrow size distribution, obtained by using novel non-hydrolytic synthetic approaches were both tested for the photocatalyzed degradation of an organic dye, Methyl Red (2-(4-DiMethylamino-phenylazo)-benzoic acid)—C.I. 13020) and their behaviour comparatively examined with respect to TiO2 and ZnO commercial powders. The experiments were carried out using semiconducting oxides under UV and visible light illumination. Preliminary studies on the influence of various experimental factors as pH and dye concentration were performed. The obtained results demonstrated a high photocatalytic efficiency of nanosized semiconducting particles.

Marco Panizza - One of the best experts on this subject based on the ideXlab platform.

  • electrochemical degradation of Methyl Red using bdd and pbo2 anodes
    Industrial & Engineering Chemistry Research, 2008
    Co-Authors: Marco Panizza, G Cerisola
    Abstract:

    The electrocatalytic properties of lead dioxide (PbO2) and boron-doped diamond (BDD) anodes were compaRed for the electrochemical incineration of Methyl Red, an azo dye, using an electrolytic flow cell with parallel-plate electrodes. The effects of several operating parameters such as current density, hydrodynamic conditions, and pH on the degradation rate and current efficiency were determined. The experimental data indicate that, on PbO2 and BDD anodes, Methyl Red oxidation takes place by reaction with hydroxyl radicals electrogenerated from water discharge. The electro-oxidation of Methyl Red was found to behave as a mass-transfer-controlled process, so that the removal rate and current efficiency were enhanced by high flow rates and independent of the pH in the range of 3.0−7.0. It was also observed that the Methyl Red decay reaction followed pseudo-first-order kinetics with a rate constant that increased slightly with applied current at the PbO2 anode but was essentially independent of current at the...

  • electrocatalytic materials for the electrochemical oxidation of synthetic dyes
    Applied Catalysis B-environmental, 2007
    Co-Authors: Marco Panizza, G Cerisola
    Abstract:

    Abstract The electrocatalytic properties of Ti–Ru–Sn ternary oxide, platinum, lead dioxide and boron-doped diamond anodes for the oxidation of Methyl Red have been compaRed by potentiodynamic measurements and bulk electrolysis. The results of the cyclic voltammetries have shown that in the potential region of supporting electrolyte stability polymeric materials, which result in electrode deactivation, are formed on the electrode surfaces. While Ti–Ru–Sn ternary oxide and platinum cannot restore their initial activity by polarization, lead dioxide and boron-doped diamond anodes can be reactivated by electrolysis in the potential region of electrolyte decomposition due to the electrogeneration of hydroxyl radicals. The bulk electrolysis showed that the complete COD and colour removal were only achieved using lead dioxide and boron-doped diamond while Ti–Ru–Sn ternary oxide and platinum only permitted a partial oxidation of Methyl Red.

Els J M Van Damme - One of the best experts on this subject based on the ideXlab platform.

  • novel cellulose and polyamide halochromic textile sensors based on the encapsulation of Methyl Red into a sol gel matrix
    Sensors and Actuators B-chemical, 2012
    Co-Authors: Lien Van Der Schueren, Karen De Clerck, Giovanna Brancatelli, Giuseppe Rosace, Els J M Van Damme
    Abstract:

    pH-sensitive chromic textiles are promising materials that can be used as flexible sensor systems providing an easily visible signal. However to date, mainly conventional dyeing techniques have been applied for obtaining these textile sensors, which limits the possibilities in terms of pH-sensitive dyes and textile types. Therefore, the more versatile sol–gel technique was studied in this paper as an alternative dye loading method. The pH-indicator Methyl Red was applied on cellulosic and synthetic textile fabrics using both a conventional dyeing and a sol–gel technique. Textile fabrics treated with sol–gel were found to show a fast and clearly visible colour change with a pH-variation. In addition, the hydrophilicity of the polymeric material affected the distribution of the dye molecules inside the fibre and as a consequence the response of the resulting sensor. Moreover, due to interactions of Methyl Red with the sol–gel matrix the halochromic behaviour of the dye changed with respect to the dye in solution. In conclusion, sol–gel showed to be a highly effective technique for the development of flexible sensors which allow for monitoring pH-variations through a colour change.

Ogunyemi E.o - One of the best experts on this subject based on the ideXlab platform.

  • Antibiotics resistance of a strain of Escherichia coli isolated from bore hole in Ile Ife, Osun state, Nigeria
    2011
    Co-Authors: Akande O.t, Ajayi A. A., Adejuwon A. O., Olutiola P. O., Ogunyemi E.o
    Abstract:

    Abstract:Escherichia coli were isolated from water from two boreholes in Ile Ife, Osun state, Nigeria. This was an indication of faecal contamination. These strains of Escherichia coli were Gram negative short rods, Catalase positive, Methyl Red positive, Voges Proskaeur negative. The strains could ferment glucose galactose, sucrose, lactose, mannitol and maltose with the production of acid and gas but could not hydrolyze starch. A particular strain was resistant to sulfamethoxazole, ampicillin, cotrimoxazole, cephaloridine, streptomycin, carbenicillin, sulfafurazole and tetracycline but sensitive to gentamicin, colistin, nalidixic acid, nitrofurantoin and colistin sulphat

  • Antibiotics resistance of a strain of Escherichia coli isolated from bore hole in Ile Ife, Osun state, Nigeria
    2011
    Co-Authors: Akande O.t, Ajayi A. A., Adejuwon A. O., Olutiola P. O., Ogunyemi E.o
    Abstract:

    Escherichia coli were isolated from water from two boreholes in Ile Ife, Osun state, Nigeria. This was an indication of faecal contamination. These strains of Escherichia coli were Gram negative short rods, Catalase positive, Methyl Red positive, Voges Proskaeur negative. The strains could ferment glucose galactose, sucrose, lactose, mannitol and maltose with the production of acid and gas but could not hydrolyze starch. A particular strain was resistant to sulfamethoxazole, ampicillin, cotrimoxazole, cephaloridine, streptomycin, carbenicillin, sulfafurazole and tetracycline but sensitive to gentamicin, colistin, nalidixic acid, nitrofurantoin and colistin sulphate