MMO titanium anode, that is, titanium-based metal oxide coated electrode, is an insoluble anode coated with a specific metal oxide coating on a titanium substrate. With its excellent performance, it has been widely used in many fields and promoted the development of related industries.
Working principle of MMO titanium anode
The working principle of MMO titanium anode is based on electrochemical principles. During the electrolysis process, the titanium substrate serves as a supporting structure, and the metal oxide coating on the surface is the active site for electrochemical reactions. When an external voltage is applied, the metal oxide coating on the surface of the anode catalyzes a specific oxidation reaction, causing the anions in the electrolyte to lose electrons on the surface of the anode, undergoing an oxidation reaction and generating corresponding oxidation products. At the same time, the titanium substrate can conduct current well to ensure the smooth progress of the electrolysis process.
Composition and structure
Titanium substrate: Usually titanium materials with higher purity are selected, such as TA1, TA2, etc. Titanium has the advantages of low density, high strength, and good corrosion resistance, and can provide stable mechanical support and good electrical conductivity for the anode.
Metal oxide coating: generally composed of oxides of metals such as ruthenium, iridium, and titanium, such as RuO₂, IrO₂, TiO₂, etc. These metal oxides have good conductivity, catalytic activity and chemical stability, can reduce the overpotential of reactions such as oxygen evolution and chlorine evolution, and improve electrolysis efficiency.
Preparation process
Titanium substrate pretreatment: The titanium material is cut and machined, and then the surface is degreased, pickled, etc. to remove impurities such as oil stains and oxide scale on the surface to improve the bonding strength between the coating and the substrate.
Coating preparation: Common coating preparation methods include thermal decomposition, sol-gel, and electrodeposition. Taking the thermal decomposition method as an example, a solution containing a metal salt is coated on the surface of the titanium substrate, and then thermally decomposed at high temperature to decompose the metal salt into metal oxides and form a uniform coating on the surface of the titanium substrate.
Post-treatment: The coated anode is subjected to post-treatment processes such as heat treatment and aging to further improve the performance and stability of the coating.
Performance characteristics
High electrocatalytic activity: can significantly reduce the overpotential of reactions such as oxygen evolution and chlorine evolution, improve the rate and efficiency of electrolytic reactions, and reduce energy consumption.
Good corrosion resistance: both the titanium substrate and the metal oxide coating have excellent corrosion resistance, can work stably for a long time in various corrosive electrolytes, and extend the service life of the anode.
Good dimensional stability: during the electrolysis process, the size and shape of the anode remain basically unchanged, ensuring the stability of the electric field distribution in the electrolytic cell, which is conducive to improving the quality and consistency of the electrolytic products.
Low resistance: the metal oxide coating has good conductivity, and the conductive properties of the titanium substrate make the overall resistance of the MMO titanium anode low, which can reduce the loss of electrical energy on the anode.
Application field
Chlor-alkali industry: It is an indispensable key component in chlor-alkali production, which can improve production efficiency, reduce energy consumption, and improve product quality. It is widely used in the production of caustic soda by diaphragm method and ion membrane method.
Electroplating industry: used in nickel plating, gold plating, chrome plating and other electroplating processes, as an anode or auxiliary anode, it can make the coating uniform and smooth, improve the coating quality, reduce the cell voltage and save electricity.
Water treatment field: can be used for seawater desalination, wastewater treatment, drinking water disinfection, etc. For example, in the electrocatalytic oxidation treatment of wastewater, it can effectively degrade organic pollutants and improve the biodegradability of wastewater.
Electrolytic organic synthesis: in the electrolytic synthesis reaction of organic compounds, as an anode material, it can promote the oxidation reaction of organic molecules and realize the synthesis of specific organic products, such as the preparation of organic acids and organic alcohols.
Battery industry: in the research and development and production of some new batteries, such as lithium-ion batteries and fuel cells, MMO titanium anodes can be used as current collectors or electrode materials, which helps to improve the performance and life of batteries.
Selection and design
Choose according to the application scenario: Different application fields have different performance requirements for anodes. For example, the chlor-alkali industry requires anodes with good chlorine evolution performance, while the electroplating industry has higher requirements for the stability and uniformity of the anode.
Consider current density and cell size: Select MMO titanium anodes of appropriate size and shape according to the size of the cell and the required electrolytic output, and determine the current density range it can withstand.
Selection of coating formula: Select appropriate metal oxide coating formula according to the composition of the electrolyte and the characteristics of the electrolytic reaction to meet specific electrocatalytic performance requirements.
Installation and maintenance
Installation requirements: During installation, ensure that the distance between the anode and the cathode is uniform to avoid short circuits and excessive local current density. At the same time, pay attention to the fixation and sealing of the anode to prevent electrolyte leakage.
Daily maintenance: Regularly check the surface condition of the anode. If the coating is damaged or detached, it should be repaired or replaced in time. Keep the electrolyte clean to prevent impurities from adhering to the surface of the anode and affecting its performance.
Cleaning and maintenance: Select appropriate cleaning methods and cleaning agents according to the type of dirt on the anode surface. For example, for some metal oxide dirt, dilute acid solution can be used for cleaning, but attention should be paid to the cleaning time and acid concentration to avoid corrosion to the anode.
Development Trend
Research and development of high-performance coatings: Continuously explore new metal oxide coating materials and formulas to further improve the electrocatalytic activity, corrosion resistance and stability of the anode to meet increasingly demanding application requirements.
Combination with new technologies: For example, combined with nanotechnology, surface modification technology, etc., to prepare MMO titanium anodes with nanostructures or special surface properties to improve their performance and application range.
Development of green and environmentally friendly anodes: With increasingly stringent environmental protection requirements, developing more environmentally friendly and energy-saving MMO titanium anodes to reduce pollutant emissions and energy consumption during electrolysis is one of the future development directions.
Market status and prospects
At present, the demand for MMO titanium anodes in the global market continues to grow. In traditional fields such as chlor-alkali, electroplating, and water treatment, its application continues to expand and deepen; in emerging fields such as new energy and environmental protection, it also shows great development potential. With the continuous advancement of technology and the gradual reduction of costs, MMO titanium anodes are expected to be used in more fields, and the market prospects are broad. As a high-performance electrode material, MMO titanium anodes play an important role in the field of electrochemistry. Through continuous technological innovation and optimization, it will make greater contributions to promoting the development and progress of related industries.
