Electrochemical Degradation of Azo Dyes using Graphene/Fto As Cathode and Platinum/Ti As Anode

One of the most water polluting impact on the environment are dyes produced in various industries, mainly textile. An estimated 10-15% of the dyes used in these industries are thrown in the waste water. Chemicals containing dyes (including azo) are related to the presence of toxic compounds with chromophores groups of high molecular weight which to accumulate in lakes and rivers causing decrease in the brightness of the water and consequently induce the decrease of photosynthetic activity and decrease in available oxygen content in the water. In this work the electrochemical degradation of organic azo dye (Disperse Blue 3) will be presented. The degradation is carried out using the technique of chronoamperometry, calculating the anodic and cathodic potential of the system using calomel reference electrode. Phosphate buffer solution (1M) at pH 7.4 will be used as a supporting electrolyte. Graphene oxide supported on tin oxide dopped with fluor (FTO) will be use as cathode active electrode and platinum on titanium as anode active electrode. All systems of electro degradation will be built inside the 1cm x 1cm x 5cm quartz cell of the ultraviolet-visible spectrophotometer and measurements will be taken insitu during the process of electrochemical degradation. The cathode and anode are in separate cells joined by a salt bridge. Experiments are performed by applying an anodic potential before and after the production of oxygen at the anode, employing a power supply after the porduction of oxygen.

The authors are grateful to CONACYT and CONCYTEG for the economic support via the projects FOMIX GTO-2012-C04-195057

REFERENCES

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