An MMO titanium anode is a titanium electrode with an active mixed metal oxide coating. It supports oxidation reactions in an electrolytic cell. The appropriate coating depends on whether the process calls for oxygen evolution, chlorine evolution or another reaction, together with the electrolyte and operating conditions.
This guide explains the construction, applications and purchasing details. For a drawing-based inquiry, start with the MMO titanium anode plate or MMO titanium anode mesh. Confirm the coating and operating duty before selecting a product.
1. How an MMO titanium anode works
The titanium substrate provides mechanical support and a current path. The conductive oxide coating provides the active surface for the anodic reaction. Grade 1 and Grade 2 titanium are common substrate choices, but the required grade, geometry and material documentation should follow the design.
MMO anodes are often described as dimensionally stable or insoluble anodes because they are not intended to dissolve like a sacrificial metal anode. These terms do not mean that the coating lasts indefinitely or that the electrode cannot release material. Coating loss, substrate passivation, fouling and mechanical damage can limit service life.
2. Oxygen-evolving and chlorine-evolving coatings
Oxygen evolution
Iridium oxide-based mixed coatings, including iridium–tantalum oxides, are used or investigated for acidic oxygen evolution. Published research on IrO2–Ta2O5-coated titanium describes activity in acidic solution. Such a coating family is a starting point for selection, not evidence that a particular supplied electrode meets your process requirements.
When evaluating an oxygen-evolving MMO anode manufacturer, ask for evidence relevant to your electrolyte, temperature, current density and duty cycle. Identify impurities, additives and any polarity reversal. Agree the coating specification, test conditions and acceptance criteria in writing.
Chlorine evolution
Ruthenium oxide-containing coatings are associated with chlorine-evolving duties in chloride electrolytes. For brine or seawater service, consider chloride concentration, hardness, contaminants, flow, temperature and cleaning. Our RuO2 titanium anode for chlorine generation provides a product inquiry route for this application.
The presence of chloride can affect reaction selectivity. Do not select an oxygen-duty or chlorine-duty coating solely from the label “MMO,” and do not assume that every mixed formulation supports both duties equally.
Platinized titanium is a separate coating choice
A metallic platinum layer on titanium is different from a mixed metal oxide coating. Where a drawing specifies platinized titanium, confirm that specification separately rather than substituting an MMO electrode based only on its shape.
3. Product forms and electrical connections
- Plate: define dimensions, flatness, holes, coated faces and mounting points. See the titanium anode plate listing.
- Mesh: specify mesh geometry, strand dimensions, active-area convention and frame details. See MMO titanium anode mesh.
- Rod or tube: provide overall dimensions, connection design and the installation environment.
- Ribbon: for distributed cathodic protection projects, review the MMO titanium ribbon anode and specify the complete system design.
Geometry affects flow, gas release, current distribution and mechanical support. Include busbars, joints, masking and contact areas in the drawing. An equal outside size does not imply equal active area or current capacity.
4. Applications and the information each needs
| Application | Selection information |
|---|---|
| Electrochlorination and hypochlorite production | Water analysis, chloride concentration, flow, current, temperature and cleaning method |
| PCB and other electroplating | Bath formulation and additives, replenishment method, current waveform and compatibility with an insoluble anode |
| Copper foil production and strip plating | Electrode geometry, gap, active area, cooling, flow and coating qualification under the intended load |
| Electrowinning and metal recovery | Leach or bath composition, impurities, target anodic reaction and operating current |
| Chlor-alkali cells | Cell technology, brine quality, membrane or diaphragm constraints and equipment-specific requirements |
| Impressed-current cathodic protection | Environment, current demand, layout, backfill where applicable, connections and design life |
| Electrochemical wastewater treatment | Water chemistry, target contaminants, reaction products and process-validation requirements |
These are application categories, not a statement that one coating is suitable for all of them. Electrocoagulation, electrochemical oxidation and disinfection use different mechanisms; a coated titanium anode is not a drop-in replacement for every treatment electrode.
5. Current density, voltage and service life
Current density is current divided by the specified active area. State the area convention, coated faces and units, especially when comparing a solid plate with mesh. For pulse operation, distinguish average current from peak current and identify reverse-current periods.
Cell voltage includes contributions from both electrodes, the electrolyte, the electrode gap and electrical connections. Lower anodic overpotential may help reduce energy demand, but a percentage saving must be supported by a comparison at the same output and operating conditions.
No single temperature, current-density or lifetime range applies to all MMO coatings. Lifetime depends on formulation, loading, electrolyte, contaminants, temperature, waveform, cleaning and installation. Agree the end-of-life criterion and distinguish an accelerated test result from a prediction of field operating years.
6. Comparing MMO, graphite and lead-based anodes
Compare electrodes within a defined process. Relevant factors include reaction selectivity, geometry stability, material consumption, product contamination, cell energy, maintenance and replacement cost. Results from one bath or current density should not be presented as a universal efficiency or lifetime advantage.
Coated titanium can avoid the need for a deliberately dissolving anode in suitable systems, but an insoluble anode changes how bath constituents are replenished. Confirm the process chemistry when replacing a soluble anode. Environmental performance also depends on the electrolyte and reaction products, not just the substrate material.
7. Manufacturing and quality evidence to request
Our MMO titanium anode manufacturing guide discusses substrate fabrication, surface preparation, coating and thermal processing. A general process description does not replace records for the supplied order.
- Approved drawing and material grade, with traceability or a material certificate if required.
- Dimensions, connections, coated area and masking checked against the drawing.
- Agreed coating family and loading or other specified coating controls.
- Inspection or electrochemical test method, operating conditions and pass criteria.
- Handling, installation, cleaning and operating instructions for the agreed duty.
Request current documents relevant to the order rather than relying on a generic certification label. Material standards for titanium do not, by themselves, establish coating performance.
8. Recoating and lifecycle review
Recoating may be considered if the substrate and connections remain suitable after inspection. Send the service history, drawings, photographs and known failure mode for review before assuming that an existing electrode can be refurbished. Recoating availability and acceptance depend on its condition and the intended new duty.
9. Questions before ordering
Can the same MMO anode produce oxygen and chlorine?
The competing reactions depend on coating composition and electrolyte conditions. Specify the intended reaction and acceptable by-products; the term MMO alone is insufficient to select the electrode.
How long will the coating last?
Request an estimate tied to a defined electrolyte, temperature, current density, waveform and failure criterion. Do not compare operating-year claims without those conditions.
What should I send for a quotation?
Provide the target reaction, complete electrolyte composition, temperature, current and active area, duty cycle, drawing, connections, quantity, required inspection documents and delivery destination. Include the existing electrode specification if this is a replacement.
10. Discuss your application with NiTiCu
Browse our titanium anode products or send your anode specifications for quotation. Shaanxi Nickel Titanium Copper Metal Co., Ltd is located in Baoji, Shaanxi, China. Coating selection, available configurations and commercial terms are confirmed for the requested application.
Email: sales@niticu.com · Phone: +86 13335373172.
