Determination of chemical oxygen demand of nitrogenous organic compounds in wastewater using synergetic photoelectrocatalytic oxidation effect at TiO2 nanostructured electrode
Author(s)
Li, Lihong
Zhang, Shanqing
Li, Guiying
Zhao, Huijun
Griffith University Author(s)
Year published
2012
Metadata
Show full item recordAbstract
and monitoring. The natural degradation of nitrogenous organic compounds (NOCs) in water requires significant amounts of oxygen. In the determination of standard COD however, NOCs are persistent compounds that cannot be completely oxidized even in the most oxidative chemical environments, i.e. the reaction media that contain high concentrations of dichromate in strong acid at high temperature. Consequently, the measured COD values of wastewater samples containing NOCs are commonly lower than theoretical COD values and do not reflect the actual oxygen demand of the water body. This problem is partially alleviated when the ...
View more >and monitoring. The natural degradation of nitrogenous organic compounds (NOCs) in water requires significant amounts of oxygen. In the determination of standard COD however, NOCs are persistent compounds that cannot be completely oxidized even in the most oxidative chemical environments, i.e. the reaction media that contain high concentrations of dichromate in strong acid at high temperature. Consequently, the measured COD values of wastewater samples containing NOCs are commonly lower than theoretical COD values and do not reflect the actual oxygen demand of the water body. This problem is partially alleviated when the photoelectrochemical method for COD determination (PeCOD) based on nanostructured TiO2 photoanode is utilized. To completely overcome this problem, a synergetic photoelectrochemical oxidation effect in thin layer cells is used to achieve complete oxidation of NOCs. This is done by the simple addition of a hydroxyl organic compound (i.e. glucose) into the test sample before the PeCOD measurement. Preliminary experimental results demonstrate that the synergetic PeCOD method provides an effective and reliable means to measure COD values of NOC-containing pollutants without the need for toxic or expensive reagents.
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View more >and monitoring. The natural degradation of nitrogenous organic compounds (NOCs) in water requires significant amounts of oxygen. In the determination of standard COD however, NOCs are persistent compounds that cannot be completely oxidized even in the most oxidative chemical environments, i.e. the reaction media that contain high concentrations of dichromate in strong acid at high temperature. Consequently, the measured COD values of wastewater samples containing NOCs are commonly lower than theoretical COD values and do not reflect the actual oxygen demand of the water body. This problem is partially alleviated when the photoelectrochemical method for COD determination (PeCOD) based on nanostructured TiO2 photoanode is utilized. To completely overcome this problem, a synergetic photoelectrochemical oxidation effect in thin layer cells is used to achieve complete oxidation of NOCs. This is done by the simple addition of a hydroxyl organic compound (i.e. glucose) into the test sample before the PeCOD measurement. Preliminary experimental results demonstrate that the synergetic PeCOD method provides an effective and reliable means to measure COD values of NOC-containing pollutants without the need for toxic or expensive reagents.
View less >
Journal Title
Analytica Chimica Acta
Volume
754
Subject
Analytical chemistry
Electroanalytical chemistry
Catalysis and mechanisms of reactions
Electrochemistry
Other chemical sciences
Chemical engineering
Nanotechnology