6 Things You Need to Know About Platinized Titanium Anodes (5)

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Manufacturing of platinized titanium anodes has evolved and improved over the last two decades. Although the electrodeposition technique for coating platinum continues to be popular, the difficulty in achieving an adherent coating on titanium has been overcome by pre-roughening the titanium surface and pre-coating the etched substrate with a very thin film of a conductive primer.

According to some studies, platinum coat thickness generally varies from one to five microns, and in special applications of cathodic protection, (the thickness) could go up to 20 microns. For the cathodic protection of onshore bridge decks, copper-cored titanium with a 2.5-micron platinum sheath has been developed. The studies have further concluded that in a concentrated NaCl solution, the platinum consumption could be less than 0.1 micrograms per ampere-hour, whereas in seawater (ten percent saturation) it could go up to one microgram per ampere-hour.

For the cathodic protection systems of power station condensers using a mixture of river and seawater, the platinum consumption rate shoots up due to the simultaneous evolution of oxygen along with chlorine, and with salty water, due to the presence of dissolved solids, the consumption of platinum rose to tens of micrograms per ampere-hour.

In the case of nickel electroplating, the presence of brightening agents could affect platinum consumption rates, whereas sugar content in the brine feedstock in the steel vessels accentuated the rate of platinum consumption.

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