Coated titanium anode, also known as titanium-based mixed precious metal oxide coated titanium anodes (mmo) or DSA anodes (Dimensionally Stable Anodes), are classified based on their functions and properties.
The main classifications include:
- Chlorine-evolving anode (Ruthenium iridium titanium anode): These are used in environments with a high content of chloride ions in the electrolyte, such as hydrochloric acid, seawater electrolysis, and brine electrolysis.
- Oxygen-evolving anode (Iridium tantalum titanium anode): Applied in electrolytes that are mainly sulfuric acid.
- Platinum-coated anode (platinum coated anode): With a titanium substrate and a precious metal platinum coating, typically with a thickness of 1-5 microns.
- Lead titanium dioxide anode:
Precautions for the use of coated titanium anode
- Installation:
Ensure the anode is firmly installed to prevent loosening during operation, which could affect current conduction and electrolysis efficiency.
Keep the spacing between electrodes uniform for a balanced electric field distribution. - Current control:
Avoid excessive current density as it might cause overheating and damage to the coating, shortening the anode’s lifespan.
Maintain stable current to prevent adverse effects on the coating due to frequent fluctuations. - Electrolyte environment:
Strictly control the content of harmful ions in the electrolyte, such as fluoride ions, cyanide ions, and sulfide ions. The fluoride ion content should generally be controlled within 100 ppm.
Keep the pH value of the electrolyte within an appropriate range. Extreme acidity or alkalinity could adversely affect the anode performance. - Operation procedures:
Do not reverse the polarity when there is no coating on the cathode to avoid damaging the anode.
Minimize frequent power outages as prolonged soaking in the solution without current can harm the coating. - Temperature control:
Be cautious of the temperature during the electrolysis process. Excessive temperature may lead to a decline in coating performance. - Regular inspection and maintenance:
Periodically inspect the anode’s appearance for any coating peeling or damage.
Promptly repair or replace anodes with issues.
For instance, in a certain chemical electrolysis production, failure to strictly control the fluoride ion content in the electrolyte led to rapid corrosion of the coating on the titanium anode, resulting in the need for premature replacement and increased production costs. Another example is that in another enterprise, improper control of the current density during use caused overheating of the anode, significantly reducing its lifespan.
In conclusion, adhering strictly to these precautions when using coated titanium anodes helps to maximize their performance, extend their service life, and enhance production efficiency.
