MMO COATED TITANIUM ANODES
Mixed metal oxide (MMO) coated titanium anodes comprise a family of electrodes made from commercially pure titanium to which an electro catalytic layer is applied by thermal decomposition. The electro catalytic layers is composed of a mixture of noble and valve metal oxides, the selection of which and their ratio is dictated by the electrolyte conditions in which the anode is immersed.
These anodes can be used to advantage in aggressive solutions or other difficult applications.
The manufacturing route of MMO coated anodes varies depending on the composition of the electro catalytic layer. In general the route involves multiple applications by thermal decomposition of mixtures of noble metals as their oxides.
A variety of shapes and forms are available including Tubular, Bar, Rod, Sheet, Wire, Disc and Mesh. Individually fabricated anodes are available to suit customers’ specific requirements.
MMO coatings can be specifically formulated to withstand the simultaneous generation of oxygen and chlorine, which occurs in dilute sea water or fresh water containing low chloride levels. MMO coated anodes are also durable in highly acidic media and are often used in deep well ground beds.
The advantages using mixed metal oxide titanium are
Improved resistance for oxygen/chlorine mixed evolution
Range of compositions for various duties available
Improved resistance in acidic media
Low wear rate
For cathodic protection applications it is anticipated that the Faradic wear rate will be approximately 0.5 to 1.0 micrograms of coating per ampere hour. Wear rates for other applications are generally low but depend on current density and other operating conditions.