Hebei Boni Tech Co.,Ltd. is a private high-tech enterprise, integrating R&D, production and sales, mainly engaged in the research and production of titanium and its precious metal coated electrodes. The company is based on customer service, and quality as fundamental, and has been with a number of domestic and foreign research institutions that have close technical exchanges to ensure the technical advantages and product advantages.
All parameters are taken from our customers in the past ten years, so please understand and correct us if there is anything wrong.
1. Substrate: Titanium
Titanium is a metallic element, gray, with atomic number 22 and a relative atomic mass of 47.867. Can burn in nitrogen, a high melting point. Passive titanium and titanium-based alloys are new structural materials, mainly used in the aerospace industry and the marine industry.
Because titanium has the characteristics of high melting point, small specific gravity, high specific strength, good toughness, fatigue resistance, acid and alkali corrosion resistance, low thermal conductivity, good high and low-temperature tolerance, and low stress under rapid cooling and rapid heating conditions, its commercial value are in Since the 1950s, it has been recognized by people and has been widely used in high-tech fields such as aviation and aerospace. And continue to promote chemical, petroleum, electric power, desalination, construction, daily necessities and other industries, titanium metal is increasingly valued by people, known as modern metal, smart metal, strategic metal, and biological metal to improve the level of national defense equipment and people. Important strategic material is indispensable to the standard of living. 1. Physical properties Pure titanium is silver-white. Compared with other metal materials, the characteristics of titanium are as follows:
1) The melting point is as high as 1660 degrees.
2) Titanium exhibits a hexagonal close-packed lattice at room temperature (below 885 degrees) and a body-centered cubic lattice above 885 degrees, with a 5.5% increase in volume.
3) The density of titanium is about 4.51g/cm3, which is about 60% of that of stainless steel, more than that of aluminum, and about 60% larger than that of aluminum.
4) Although the tensile strength of pure titanium is 350-700MPa, the titanium alloy can reach 700-1200MPa, or even 1400MPa. Therefore, the specific strength of titanium alloys (that is, the ratio of strength to density) is greater than that of any other material at present.
5) The specific heat, thermal conductivity and resistivity of titanium are at the same level as those of stainless steel, but the expansion coefficient of titanium is 50% smaller than that of steel. Titanium has poor thermal conductivity and poor electrical conductivity, similar to stainless steel.
6) The Young’s modulus of titanium is smaller than that of stainless steel, and it can bend under lower stress.
7) Follow stable creep characteristics in the temperature range of 200-300 °C.
2. Chemical properties
1) At room temperature, titanium is not easy to react with an inorganic acid, but it can react after heating.
2) The reaction of titanium with alkali solution is very slow, and it does not react with dilute alkali solution.
3) Interaction with non-metals In general, titanium is not very active, but at high temperatures, titanium can directly form very stable, hard and insoluble interstitial compounds with many non-metallic elements.
4) An important property of titanium is its ability to strongly absorb gases (oxygen, nitrogen, hydrogen). The role of titanium and oxygen and nitrogen is irreversible, so titanium is a good getter. The hydrogen absorbed in titanium can be discharged from the metal when it is heated to 800-900 degrees in a vacuum.
2. Titanium Anode
In 1965, Dr. H. Beer of the Netherlands invented the ruthenium-titanium-coated titanium electrode. That is, with metal titanium as the matrix, the ruthenium salt and the alcohol solution of the titanium salt are coated on the surface of the titanium matrix, and the salts are decomposed and oxidized by sintering to form a layer of Ru-TiO2 solid solution that is firmly combined with the titanium matrix. The ruthenium-titanium-coated electrode is based on the valve metal titanium, and its mechanical strength is large, which overcomes the shortage of the shape change of the graphite electrode during use, and the electrode material has since entered the era of titanium electrodes. Titanium electrodes with different properties can be obtained by designing coatings with different chemical formulations. After nearly half a century of development, titanium electrodes have developed into a huge system.
The full name of the titanium anode is the titanium-based metal oxide-coated anode (MMO). Also called DSA anode, dimensionally stable anode. It uses titanium as the base material (wire, rod, tube, plate, mesh), and brushes the noble metal coating on the titanium substrate so that it has good electrocatalytic activity, electrical conductivity and oxidation resistance. Compared with pristine graphite anodes and lead anodes, titanium electrodes have the following advantages:
- The electrode size is relatively stable, and the distance between the electrodes will not change during the electrolysis process, ensuring that the electrolysis operation is carried out under the condition that the cell voltage is stable ;
- High catalytic activity and low operating voltage;
- The working voltage is low, so the power consumption is small, and the DC power consumption can be reduced by 10%—20 %;
- Titanium anodes have a long working life. Metal anodes in the Chlor-alkali industry produced by the diaphragm method are resistant to chlorine and alkali corrosion. The life of the anode has reached more than 5 to 7 years, while the graphite anode is only 8 months ;
- It can overcome the dissolution problem of graphite anode and lead anode, and avoid the pollution of electrolyte and cathode products, thus greatly improving the purity of metal products ;
- It can improve the current density and increase the electrolysis efficiency;
- The oxides of noble metals iridium and ruthenium have oxidation resistance, so titanium electrodes have strong corrosion resistance ;
- It can avoid the short circuit problem after the deformation of the lead anode, so as to improve the work efficiency ;
- Titanium electrodes are light in weight, which can reduce labor intensity compared with graphite anodes and lead anodes ;
- Under the premise of no damage, the substrate can be used repeatedly ;
Titanium anode classification:
1. Ruthenium-coated titanium electrode (10g ruthenium 2g iridium/square meter standard)
This type of electrode has low chlorine evolution overpotential and high oxygen evolution overpotential and is mainly used in various chlorine evolution occasions, such as the Chlor-alkali industry, cathodic protection, sodium hypochlorite production, sewage treatment, etc. Such electrode coatings include the original Ru-Ti coating (Ru-Ti) and Ru-Ir-Ti, Ru-Co-Ti, Ru-Co-Sn-Ti, Ru-Sn-Ti, Ru-Ir-Ti, Ru-Co-Ti, Ru-Co-Sn-Ti, Ru-Sn-Ti, Ru-Si-Ti, Ru-Ti-Zr, Ru-Ti-La, Ru-Ti-Ce and other coatings.
2. Iridium-coated titanium electrode (10g iridium/square meter standard)
In the electrolysis process, such as electrolytic extraction of non-ferrous metals, electroplating industry, electrochemical reduction of organic matter, etc., the design reaction of the anode is the oxygen evolution reaction, and the electrolyte has a particularly strong oxidizing property, such as sulfuric acid, nitric acid, hydrogen peroxide and other environments. Therefore, it is hoped to develop an anode material with corrosion resistance and low oxygen evolution overpotential, and the iridium-coated titanium electrode is developed under this background. Such electrode coatings include Ir-Ta, Ir-Ta-Co, Ir-Ta-Sn and other coatings. Among them, the Ir-Ta coated titanium electrode is the most successful oxygen evolution electrode.
Tantalum is a base metal, but tantalum is a stabilizer. After adding the same molar mass of tantalum to the iridium coating, the service life of the anode in the strong oxidizing solution can be greatly improved.
3. Platinum-plated anode: titanium is the base material. The surface is plated with precious metal platinum, and the thickness of the coating is generally 1-5um. (standard according to coating thickness)
Platinum electrodes are suitable for small electrolysis applications, in hydrogen evolution environments.
3. Introduction to the production process
1. Purchase TA1 type titanium substrate (compared with TA2, which has lower iron and oxygen content, higher purity, and better electrode effect.), make sure that the surface of the board is smooth and smooth, without deep scratches and defects.
2. Machining, folding, threading, welding and forming of the selected titanium substrate, processing it into the specifications and dimensions required by customers and ensuring tolerances.
3. The titanium substrate is annealed and leveled at a temperature of >500°C. (To relieve stress and ensure flatness.)
4. During the annealing and leveling treatment, a dense titanium oxide layer will be formed on the surface of the titanium substrate, which is polished mechanically or artificially to make the surface of the titanium metallic luster.
5. Use a 10% concentration of oxalic acid to pickle and corrode the titanium substrate, and carry it out for several hours in a slightly boiling state, so that the surface oxide layer is etched into a titanium hydride surface with a surface roughness of 5 microns.
6. Carry out the reasonable qualitative and quantitative configuration of the precious metal solution according to the anode environment used by customers.
7. Check that the acid-washed titanium substrate is qualified, that is, the surface layer is a gray and uniform pockmarked surface structure, and then artificially coated, sintered at a suitable temperature, and cooled naturally after sintering, and the second coating is carried out when it is cooled to room temperature. Run until more than 12 to 20 times the configuration solution is applied.
8. After the sintering of the above-processed parts is completed, the life test is carried out with the furnace test piece, and the test is qualified and packaged for delivery.
4. The main application area
1. Electrolytic production of Chlor-alkali industry and chlorate industry
The chemical industry that produces chlorine, hydrogen and caustic soda by electrolyzing salt solution is called the Chlor-alkali industry.
In addition to the above, the downstream products of hydrogen chloride (the aqueous solution is hydrochloric acid), sodium hypochlorite, chlorinated stone, polyvinyl chloride ( PVC for short ) can also be prepared. Polyvinyl chloride polymer = PVC molecular structure ) , hydrogen peroxide, etc.
In the production of Chlor-alkali, pure saturated brine is used as the electrolytic solution, titanium electrode is used as the anode, and asbestos wool with iron mesh is used as the cathode. The anode chamber produces chlorine gas, and the cathode chamber produces hydrogen and sodium hydroxide. in production.
The application of titanium anode has greatly promoted the development of the Chlor-alkali industry and is an epoch-making contribution to the field of electrochemistry. The electrode has high catalytic activity for chlorine evolution, good electrocatalytic activity, mechanical stability and chemical stability for chlorine evolution reaction. It is an irreplaceable electrode material in today’s Chlor-alkali industry, with a service life of more than five years.
Because of the high power consumption and high salt consumption in the Chlor-alkali industry, especially in the production of the diaphragm method, the country has abolished the production, and now ion membrane electrolysis is the main method.
2. Sodium hypochlorite generator, chlorine dioxide generator electrode manufacturing. (84 disinfectant)
Sodium hypochlorite is a strong oxidant. It is a truly efficient, broad-spectrum and safe strong sterilization and virus-killing agent. It has a strong bactericidal effect and can replace oxidants such as bleaching powder.
According to chemical determination, sodium hypochlorite at ppm level is almost completely hydrolyzed to hypochlorous acid in the water, and its efficiency is higher than 99%. In the process of sterilization and virus killing, hypochlorous acid can not only act on the cell wall and virus shell, but also penetrate into the body of bacteria (viruses) due to its small molecules and no charge, and interact with bacteria (viruses) body proteins, Nucleic acids, enzymes and other organic macromolecules undergo oxidation reactions to kill pathogenic microorganisms.
Since the Spring Festival of 2020, due to the outbreak of the new crown epidemic in the country and the world, the demand for disinfection and sanitary protection products is in short supply, and the public’s awareness of sterilization and disinfection has increased, and many manufacturers of multi-purpose disinfection instruments have been born. Because of its simple principle and convenient production, only 10 grams of salt water + 600 mA current can obtain a 2000PPm grade 84 disinfectant.
The appearance of electrode products: plate, mesh, tube, etc., our company provides long-term supply for enterprises in Beijing, Chongqing, Guangdong Foshan, Zhongshan, Baoan, Shandong Weifang, Jiangsu Yixing, Hunan Hengyang, etc. The current density is 30~60A, and the voltage is 24V.
3. Recycling of etching waste liquid from PCB electronic circuit board factory
Etching is an important process in the production of printed circuit boards. As the etching proceeds, the waste etching solution contains a large number of copper ions or other metal ions, which can be recycled by electrolysis. Through this recycling process, enterprises not only increase economic benefits by recovering metals such as copper but also achieve long-term social benefits by meeting emission standards and recycling resources.
Waste liquids include etching liquid waste liquid, micro-etching liquid waste liquid, alkaline etching waste liquid, acid etching waste liquid, low copper-containing waste liquid, waste fixing liquid, waste frame material, nickel-containing waste liquid, gold and palladium-containing waste liquid, waste in the water.
4. Cathodic protection
In the marine, hull, bridge and other steel use environments, due to the corrosion of impurities in the steel and micro-battery, and the complex natural environment, although corrosion-resistant alloy steel is selected and the thickness of the material is increased to coat with excellent corrosion-resistant paint, this Corrosion of structures is still very serious, posing a great threat to safety production, and cathodic protection is a convenient and important measure to effectively protect permanent steel structures in the ocean.
1) Using an impressed current to make the entire surface of the protected metal structure become a cathode, which is called impressed current cathodic protection.
2) Connect a metal or alloy with a more negative potential to the metal equipment to be protected, called sacrificial anode protection.
Applied to the following areas:
1) In fresh water and seawater, prevent corrosion of ships, docks, platforms, gates and cooling equipment.
2) In alkali and salt solutions, prevent the corrosion of storage tanks, evaporation tanks, boiling alkali pots, etc.
3) Prevent corrosion of pipelines and cables in soil and sea mud.
5. Sewage treatment
With the rapid development of industry and agriculture and population growth, the amount of sewage discharged by humans has increased sharply, resulting in many drinks of water suffering from different degrees of pollution. Electrochemical treatment of sewage is divided into direct electrolysis and indirect electrolysis.
1) Direct electrolysis refers to the removal of pollutants from wastewater by direct oxidation or reduction on the electrodes. Direct electrolysis can be divided into cathodic processes and anodic processes. The anode process refers to the oxidation of pollutants on the anode surface and the conversion into less toxic substances or easily biodegradable substances, and even the inorganization of organic substances, so as to achieve the purpose of reducing pollution. The cathode process refers to the reduction of pollutants on the cathode surface. It is mainly used for the reductive dehalogenation of halogenated hydrocarbons and the recovery of heavy metals.
2) Indirect electrolysis refers to the use of electrochemically generated redox substances as reactants or catalysts to convert pollutants into less toxic substances. Indirect electrolysis can be divided into reversible and irreversible processes. The reversible process refers to the electrochemical regeneration and recycling of redox substances in the electrolysis process; the irreversible process refers to the oxidation of organic substances with substances produced by irreversible electrochemical reactions.
It is used in printing and dyeing wastewater treatment, landfill leachate treatment, fecal wastewater treatment, cyanide-containing wastewater treatment, pharmaceutical wastewater treatment, hospital wastewater treatment, and organic wastewater treatment.
In order to effectively remove COD and BOD and ensure a large electrolysis area, assembled electrodes and parallel electrolysis are required for sewage treatment, and most of them have a mesh structure.
6. Circulating water softening
In the application environment of circulating water, due to the presence of calcium and magnesium ions in the water, long-term operation of equipment or pipelines will cause scaling of equipment pipelines, resulting in increased resistance or even blockage. Second, for boilers, scaling leads to a decrease in heat transfer efficiency and waste of energy. The third is the breeding of bacteria, which will cause bodily harm to humans and animals.
Using the principle of cathodic reduction, one is to place a special titanium electrode mesh cylinder in a circulating water tank. As the electrolysis proceeds, calcium and magnesium ions in the water can be adsorbed on the cathode mesh, which can effectively remove metal ions in the water and achieve the effect of softening the water. The other is to pass the circulating water through the descaling box, absorb calcium and magnesium ions and discharge it.
7. Gold-plated, steel galvanized and tin-plated
Titanium electrodes have excellent electrical conductivity and corrosion resistance, and their service life is much higher than that of lead anodes. They can work stably for more than 4,000 hours and have low costs. It will be an inevitable trend in the development of electro-galvanizing and tin production at home and abroad.
Titanium electrodes are currently used in Japan, the United States, Germany, and China, which not only greatly saves the energy consumption of electroplating, but also creates conditions for the production of thick galvanized and tin steel plates because it can increase the current density of electroplating.
8. Non-ferrous metal extraction
Electrolytic metallurgy occupies a large proportion in the hydrometallurgy industry. The non-ferrous metals produced by electrolytic metallurgy include Zn, Cd, Cu, Mn, Co, Ni, Cr, etc.
The advantage of electrolytic metallurgy is that it has high selectivity, can obtain high-purity metals, and can recover useful metals. Therefore, it can process low-grade minerals and polymetallic ores with complex components, which is beneficial to the comprehensive utilization of resources. In addition, the pollution to the environment is small, and the production is easier to be continuous and automated.
Coated titanium electrodes have been widely used in the field of electrolytic extraction of metals in recent years, and it has become the second industrial field to use titanium electrodes on a large scale.
9. Electrolytic copper foil
With the development of science and technology, the degree of automation is increasing day by day, which has promoted the rapid development of the electronics industry. The application of large-scale integrated circuits has increased the demand for copper foil in the electronics and instrumentation industry, and the quality requirements of copper foil are also getting higher and higher.
According to the thickness, it can be divided into 105µm, 70µm, 35µm, 18µm, 12µm, 9µm and 5µm, among which copper foil below 12µm is generally called ultra-thin copper foil.
The electrolytic copper foil uses a metal roller partially immersed in a copper sulfate solution that rotates continuously as the cathode, and the foil is produced by continuous electrolysis. Internationally, the production of copper foil is mainly controlled by Japan, and there are about 15 domestic production enterprises with a production capacity of about 35,000 tons.
10. Electrolyzed functional water electrolyzed functional water tank
Functional water is defined as water that can obtain various useful functions through artificial treatment. Electrolyzed water is popular as a sterilization treatment technology with good sterilization effect, strong practicability and no secondary pollution. The functional water is produced by electrolyzing drinking water or a trace amount of salt water through titanium electrodes, which is widely used in electrolysis water machines.
1) Use electrolysis to generate hypochlorite, new ecological oxygen, hydroxyl radicals and other strong oxidizing substances to kill microorganisms.
2) Use electrolytic electrodes to directly act on microorganisms to make them die.
3) Alkaline ionized water can directly treat a variety of diseases, effectively improve the metabolic function of the human body, eliminate free radicals of harmful acidic metabolites, and enhance physical fitness to prevent and improve disease resistance.
4) Acidic ionized water has the effect of inhibiting the growth of bacteria, and the effect is the same as that of beauty astringent water, and it uses strong oxidizing properties for sterilization and disinfection; alkaline ionized water is used to regulate human physiological functions.
Our company’s YC -90 ionized water electrolyzer has the characteristics of reasonable structure, low energy consumption, wide range of applicable water quality, reliable performance, long life, easy cleaning, etc. The tank body is made of ABS plastic with good thermal stability; the electrode is made of titanium-based sintered platinum Group metal alloy, high conductivity, non-toxic, good oxidation resistance, good inversion performance, long service life, in line with national drinking water safety standards.
Installation size : 185 X 44 X 70mm / Model : YC -90 / Water output : 90～120 l/h / Plate material : TA1 / Housing material : ABS plastic / Overcurrent density : 5000A / Voltage≤ 24 V / ORP Value : less than -250mV / service life : 5-10 years (depending on water quality) / PH value alkaline 7.5-10 acid 6.5-3.5 / tank structure : five poles and four tanks / heavy metal and toxic substances are precipitated : None . Instructions for use: This electrode can be used as a lead, that is, any terminal of the DC power connection is positive, and the other end is negative. Use a tee to connect one side for the water inlet, and the other end for the acidic water and alkaline water outlets. The water quality varies from place to place, and the resistivity of the water is different. Therefore, gradually increase the voltage ( between 24 volts and 30 volts) or current after the water is passed, until the water outlet is suitable for acid-alkaline water. If there are further requirements for the PH value, add 0.3% salt water to continue the measurement.
5. Enterprise advantages
1. We own titanium base material and original Heraeus precious metal ruthenium trichloride and chloroiridic acid ensure the reliability of raw material quality from the source.
2. The company is located in Hebei and has its own CNC lathes and other machining equipment, which effectively guarantees the production schedule and precision control.
3. The company continuously improves the sintering device, improves the operating environment, and ensures the stability of production.
4. The company has accumulated many years of anode production experience and has a group of skilled operators. On this basis, the process is continuously optimized to make the products more competitive in the market.
6. Precautions for the use of electrodes
1. After the titanium electrode is oxidized and sintered, it is a black surface of ruthenium dioxide and iridium dioxide or iridium dioxide and tantalum pentoxide, and the black side correspond to the cathode; the uncoated surface is blue or gray. The surface does not have electrode properties.
2. Once the titanium electrode substrate is pickled, all subsequent production and processing procedures and use must be carried out strictly and carefully. When moving, installing and disassembling, wear clean gloves to get stuck at both ends or edges of the anode. It is strictly forbidden to scratch any foreign objects on the surface of the coating layer .
Note: The titanium substrate itself is not conductive, and its outer layer is coated with a noble metal oxide coating that has electrocatalytic activity, conductivity, and oxidation resistance, but its thickness is only about 10 microns. During the process, the electrode will not only corrode from the damage, thereby affecting the quality and effect of the entire electrode , and the titanium anode will greatly reduce the service life due to the instantaneous high current loading.
3. The electrolyte maintains stability, especially can not contain cyanide ions and fluoride ions , these impurities will seriously corrode the titanium matrix;
4. Add a filter device before the electrolyte enters the electrolytic cell, and cannot contain metal particles with a diameter greater than 1.0mm to prevent excessive aggregation and lead to short circuit of cathode and anode.
5. When recovering copper, nickel, gold, silver, cobalt and other metals by electrolysis, the cathode attachment should not be too thick. When the titanium electrode is initially used, the electrical conductivity is the best and the copper extraction efficiency is high. Therefore, it is especially necessary to monitor the timing of copper stripping at the beginning. , in order to prevent the short-circuit breakdown of the cathode and anode due to the too small electrode spacing or the formation of metal thorns.
6. The distance between cathode and anode can be set according to actual production, generally 3-25mm. Generally speaking, the pole distance will increase the voltage drop, but it should not be too small, otherwise the cathode scale generated on the cathode surface will easily cause a short circuit of the pole plate, resulting in honeycomb electrical corrosion on the anode and cathode surface ;
7, to avoid the use of inverted poles. Once the noble metal oxide coating is used as a cathode, the surface undergoes a reduction reaction, which is easily converted into a metal element, and cannot be effectively combined with the titanium base, causing the coating to fall off; if pure titanium is used as an anode, the intense oxidation reaction on the surface will cause the coating to fall off. It makes the titanium material especially easy to be dissolved.
8. It is not advisable to soak in the solution in the power-off mode for a long time during the shutdown, and it is best to load a small current of about 5A to protect the plate.
9. During shutdown or other maintenance conditions, add dilute acid or clean the surface of the electrode with clean water, but do not wash it with nylon or mechanical substances.
10. The temperature of the electrolyte should not be too high during operation, the ideal temperature is 25-40 °C , and a heat exchange device can be added to maintain the best use environment for the Anode.
11. The normal working current density is less than 2000A/m², the current is too large, the reaction is too intense, and the life of the anode is shortened;
12. When starting up, load the current to the electrolytic cell step by step, do not lift it to the position at one time, and the same is true when it is stopped.
13. Keep the anode clean during production and use, and can not be contaminated with oil or other attachments, so as not to affect the electrolysis effect and the life of the electrode.
14. In the same electrolysis environment, different titanium anodes have different conductivity. The more precious metals are added, the greater the conductivity, catalytic activity, and anti-oxidation performance of the anode. Therefore, in industrial operations, especially in the initial use stage of the anode, operators are required to observe closely and master the rules to prevent the occurrence of cathode adhesion. The situation that the electrode plate breaks down due to too much or too fast growth.
15. The ruthenium-iridium electrode has the property of chlorine evolution. In the process of electrolyzing salt water or sewage, the concentration of the electrolyte must be guaranteed, such as 3~5% of the salt water, otherwise, the anode will react with oxygen evolution when it is close to pure water, and oxygen molecules will enter the coating. layer and titanium substrate, causing fatal damage to the coating.
16. Anode electrolysis needs a stable DC power output guarantee, that is, the smaller the ripple (clutter) coefficient of the rectifier, the better the output parameters; otherwise, the worse. The ripple factor cannot exceed 5%.
1 7. The anode has life, ensuring the stability of production is more beneficial to prolonging the service cycle.
