The Experts below are selected from a list of 76830 Experts worldwide ranked by ideXlab platform

Isao Karube - One of the best experts on this subject based on the ideXlab platform.

  • photocatalytic sensor for the determination of Chemical Oxygen Demand using flow injection analysis
    Analytica Chimica Acta, 2001
    Co-Authors: Satoshi Sasaki, Kazuhito Hashimoto, Kazuyoshi Yano, Kazunori Ikebukuro, Isao Karube
    Abstract:

    Abstract A photocatalytic sensor for the determination of Chemical Oxygen Demand (COD) with flow injection analysis (FIA) based on the photocatalysis of organic compounds in the presence of titanium dioxide (TiO 2 ) beads in a photoChemical column is described. The sensor was developed in conjunction with TiO 2 beads in the photoChemical column and with an Oxygen electrode as the sensing part. The sensor signal was observed as a result of the detection of dissolved Oxygen changes due to photocatalytic oxidation of organic compounds in the sample solution. This sensor responded linearly to the COD Mn of artificially treated wastewater (AWW) in the range of 0.12–8 ppm. A complete analysis, including sampling and washing, took about 10 min. The sensor was stable for over 15 days and has successfully been applied to the determination of COD in lake samples.

  • photocatalytic sensor for Chemical Oxygen Demand determination based on Oxygen electrode
    Analytical Chemistry, 2000
    Co-Authors: Satoshi Sasaki, And Kazunori Ikebukuro, Kazuhito Hashimoto, Isao Karube
    Abstract:

    The construction and performance evaluation of a novel Chemical Oxygen Demand (COD) sensor is described. The sensor measures, using an Oxygen electrode, a decrease of dissolved Oxygen of a given sample resulting from photocatalytic oxidation of the organic compounds therein. As the photocatalyst, titanium dioxide (TiO2) fine particles adsorbed on a translucent poly(tetrafluoroethylene) (PTFE) membrane was used. The Oxygen electrode with the membrane attached on its tip was used as the sensor probe. The operation characteristics of the sensor are demonstrated using an artificial wastewater and real water samples from lakes in Japan. This method is considered to be reliable, in that the observed parameter is close to the theoretical definition of Chemical Oxygen Demand (COD), the amount of Oxygen consumed for oxidation of organic compounds.

Satoshi Sasaki - One of the best experts on this subject based on the ideXlab platform.

  • photocatalytic sensor for the determination of Chemical Oxygen Demand using flow injection analysis
    Analytica Chimica Acta, 2001
    Co-Authors: Satoshi Sasaki, Kazuhito Hashimoto, Kazuyoshi Yano, Kazunori Ikebukuro, Isao Karube
    Abstract:

    Abstract A photocatalytic sensor for the determination of Chemical Oxygen Demand (COD) with flow injection analysis (FIA) based on the photocatalysis of organic compounds in the presence of titanium dioxide (TiO 2 ) beads in a photoChemical column is described. The sensor was developed in conjunction with TiO 2 beads in the photoChemical column and with an Oxygen electrode as the sensing part. The sensor signal was observed as a result of the detection of dissolved Oxygen changes due to photocatalytic oxidation of organic compounds in the sample solution. This sensor responded linearly to the COD Mn of artificially treated wastewater (AWW) in the range of 0.12–8 ppm. A complete analysis, including sampling and washing, took about 10 min. The sensor was stable for over 15 days and has successfully been applied to the determination of COD in lake samples.

  • photocatalytic sensor for Chemical Oxygen Demand determination based on Oxygen electrode
    Analytical Chemistry, 2000
    Co-Authors: Satoshi Sasaki, And Kazunori Ikebukuro, Kazuhito Hashimoto, Isao Karube
    Abstract:

    The construction and performance evaluation of a novel Chemical Oxygen Demand (COD) sensor is described. The sensor measures, using an Oxygen electrode, a decrease of dissolved Oxygen of a given sample resulting from photocatalytic oxidation of the organic compounds therein. As the photocatalyst, titanium dioxide (TiO2) fine particles adsorbed on a translucent poly(tetrafluoroethylene) (PTFE) membrane was used. The Oxygen electrode with the membrane attached on its tip was used as the sensor probe. The operation characteristics of the sensor are demonstrated using an artificial wastewater and real water samples from lakes in Japan. This method is considered to be reliable, in that the observed parameter is close to the theoretical definition of Chemical Oxygen Demand (COD), the amount of Oxygen consumed for oxidation of organic compounds.

Filomena M G F C Camoes - One of the best experts on this subject based on the ideXlab platform.

  • optimization of the determination of Chemical Oxygen Demand in wastewaters
    Analytica Chimica Acta, 2011
    Co-Authors: Alexandra Viana M E Da Silva, Ricardo Bettencourt J N Da Silva, Filomena M G F C Camoes
    Abstract:

    Chemical Oxygen Demand (COD) is one of the most relevant Chemical parameters for the management of wastewater treatment facilities including the control of the quality of an effluent. The adequacy of decisions based on COD values relies on the quality of the measurements. Cost effective management of the minor sources of uncertainty can be applied to the analytical procedure without affecting measurement quality. This work presents a detailed assessment of the determination of COD values in wastewaters, according to ISO6060:1989 standard, which can support reduction of both measurement uncertainty and cost of analysis. This assessment includes the definition of the measurement traceability chain and the validation of the measurement procedure supported on sound and objective criteria. Detailed models of the measurement performance, including uncertainty, developed from the Differential Approach, were successfully validated by proficiency tests. The assumption of the measurement function linearity of the uncertainty propagation law was tested through the comparison with the numerical Kragten method. The gathered information supported the definition of strategies for measurement uncertainty or cost reduction. The developed models are available as electronic supplementary material, in an MS-Excel file, to be updated with the user's data.

M Del Remedio Hernandez - One of the best experts on this subject based on the ideXlab platform.

  • ultrasound assisted method for determination of Chemical Oxygen Demand
    Analytical and Bioanalytical Chemistry, 2002
    Co-Authors: Antonio Canals, M Del Remedio Hernandez
    Abstract:

    A method for determination Chemical Oxygen Demand (COD) assisted by use of ultrasound has been successfully evaluated for the first time. The method uses instrumentation simpler and cheaper and, in some instances, safer than that used by previous methods for the same purpose. The new device used for sonication is an all-glass cylindrical sonotrode that can be introduced directly into the reaction mixture. Use of this device enables more efficient interaction between sample and ultrasonic energy. The optimized experimental conditions are high ultrasonic power (55% amplitude, 0.9-second pulses each second), high sulfuric acid concentration (>60%), and a sonication time of 2 min. Under these conditions the method has limitations similar to those of the official COD method with regard to the type of organic compound. It works adequately with easily oxidized organic matter (potassium hydrogen phthalate and dextrose) and other organic compounds difficult to oxidize by conventional methods (e.g. phenol and acetic acid) but the COD values obtained with volatile compounds and difficult organic matter are poor. Chloride is tolerated up to a concentration of 7000 mg L–1 without any masking agent. Gasification of the sample is recommended to improve results; use of air and argon resulted in no significant differences – bubbling with air during sonication resulted in COD values for certified materials and real wastewater samples statistically identical with the certified COD values and those obtained by the classic (open reflux) method. The use of ultrasound energy for COD determination thus seems to be an interesting and promising alternative to conventional oxidation methods used for the same purpose.

Kazuhito Hashimoto - One of the best experts on this subject based on the ideXlab platform.

  • photocatalytic sensor for the determination of Chemical Oxygen Demand using flow injection analysis
    Analytica Chimica Acta, 2001
    Co-Authors: Satoshi Sasaki, Kazuhito Hashimoto, Kazuyoshi Yano, Kazunori Ikebukuro, Isao Karube
    Abstract:

    Abstract A photocatalytic sensor for the determination of Chemical Oxygen Demand (COD) with flow injection analysis (FIA) based on the photocatalysis of organic compounds in the presence of titanium dioxide (TiO 2 ) beads in a photoChemical column is described. The sensor was developed in conjunction with TiO 2 beads in the photoChemical column and with an Oxygen electrode as the sensing part. The sensor signal was observed as a result of the detection of dissolved Oxygen changes due to photocatalytic oxidation of organic compounds in the sample solution. This sensor responded linearly to the COD Mn of artificially treated wastewater (AWW) in the range of 0.12–8 ppm. A complete analysis, including sampling and washing, took about 10 min. The sensor was stable for over 15 days and has successfully been applied to the determination of COD in lake samples.

  • photocatalytic sensor for Chemical Oxygen Demand determination based on Oxygen electrode
    Analytical Chemistry, 2000
    Co-Authors: Satoshi Sasaki, And Kazunori Ikebukuro, Kazuhito Hashimoto, Isao Karube
    Abstract:

    The construction and performance evaluation of a novel Chemical Oxygen Demand (COD) sensor is described. The sensor measures, using an Oxygen electrode, a decrease of dissolved Oxygen of a given sample resulting from photocatalytic oxidation of the organic compounds therein. As the photocatalyst, titanium dioxide (TiO2) fine particles adsorbed on a translucent poly(tetrafluoroethylene) (PTFE) membrane was used. The Oxygen electrode with the membrane attached on its tip was used as the sensor probe. The operation characteristics of the sensor are demonstrated using an artificial wastewater and real water samples from lakes in Japan. This method is considered to be reliable, in that the observed parameter is close to the theoretical definition of Chemical Oxygen Demand (COD), the amount of Oxygen consumed for oxidation of organic compounds.