How Platinum Anode is Used for Electrochemical Wastewater Treatment

May 12, 2021

How Platinum Anode is Used for Electrochemical Wastewater Treatment?

Platinum, widely used as an industrial catalyst, has been studied as the anode to decompose the
bio-refractory compounds such as phenol, bisphenol-A and wastewater from tannery and textile industries.

The main advantages of using the platinum metals include long service life and excellent catalysis
towards certain reactions. However, its use is limited for a number of reasons. Foremost is the cost of the material.

To reduce the amount of precious metal and maximize the catalytic area, Platinum is also deposited on the surface of other materials such as titanium or glassy carbon, but the cost is still too high in terms of treatment of pollutants. Moreover, significant loss of the precious metal was found with Pt-coated titanium.

With the advance of DSA, the coating was replaced by metallic oxides possessing similar catalytic ability. Apart from cost, the platinum catalyst has the disadvantage of low current efficiency towards the complete electro-oxidation of organics.

A comparative study found that the initial current efficiency in the electro-oxidation of organic compounds did not exceed 30%, far less than what can be achieved by an oxide-based material such as a SnO2 anode. Later the theory of hydroxyl radical formation explained the essential difference in the anodes varying in the current efficiency. Platinum is active and favors the further oxidation of hydroxyl radicals towards oxygen, which lowers its ability to oxidize organics.