Manganese Dioxide MnO2 CAS 1313-13-9
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Manganese Dioxide MnO2 CAS 1313-13-9
  • Manganese Dioxide MnO2 CAS 1313-13-9

Manganese Dioxide MnO2 CAS 1313-13-9

Item No.: TR-MnO2 Manganese dioxide is a black amorphous powder or black rhombic crystals. Solubility: Difficult to dissolve in water, weak acid, weak base, nitric acid, cold sulfuric acid, and dissolve in conc.Purity: 96.6%,72%.Particle Size: 1-3um

About Manganese Dioxide MnO2:
Manganese dioxide is an inorganic compound with the chemical formula MnO2, which exists in the form of pyrolusite in nature. Physical properties: black amorphous powder, or black orthorhombic crystals. Solubility: hardly soluble in water, weak acid, weak base, nitric acid, cold sulfuric acid, pulverize concentrated hydrochloric acid under heating to produce chlorine.


If you want to know manganese dioxide price/MnO2 price/manganese oxide price, please send inquiry to sales1@rboschco.com

 
MnO2 is an alpha polymorph that can incorporate various atoms (and water molecules) in the "tunnels" or "channels" between the manganese oxide octahedrons. People are very interested in α-MnO2 as a possible cathode for lithium-ion batteries.
 
Manganese dioxide is an amphoteric oxide. It is a very stable black powdery solid at room temperature and can be used as a depolarizer for dry batteries. It is often used in the laboratory to produce chlorine by its oxidizing property and the action of concentrated HCl. Manganese dioxide is a strong oxidant in acidic media. Manganese dioxide is an [MnO₂] octahedron. The oxygen atom is on the top of the octahedron, and the manganese atom is in the octahedron. [MnO₂] octahedrons are connected together to form a single or double chain. These chains and other chains co-top to form The tunnel structure of voids, octahedrons or hexagonal close-packed, or square close-packed.

Manganese 2 oxide is an amphoteric oxide, and there is a corresponding salt in the form of a perovskite structure such as BaMnO3 or SrMnO3 (obtained by a compound reaction in a molten alkali system), and manganese tetrachloride is also present.
 
When electrolytic manganese dioxide encounters a reducing agent, it is oxidizing. For example, manganese dioxide is heated in a stream of hydrogen to 1400K to obtain manganese oxide; manganese dioxide is heated in a stream of ammonia to obtain brown-black manganese trioxide; the manganese dioxide is reacted with concentrated hydrochloric acid to obtain l chlorine Manganese, chlorine and water.

When manganese dioxide encounters strong oxidants, it also exhibits reducibility. If manganese dioxide, potassium carbonate and potassium nitrate or potassium chlorate are mixed and melted, a dark green melt can be obtained, and the melt can be dissolved in water and cooled to obtain potassium manganate, a compound of hexavalent manganese.

Manganese dioxide is a strong oxidant in acidic media. It is used as a catalyst in the decomposition of potassium chlorate [KClO3] and the decomposition of hydrogen peroxide (hydrogen peroxide, H2O2).

Due to the strong oxidant, manganese dioxide does not burn by itself, but it supports combustion and should not be placed with flammable materials. Feel free to send an inquiry to get the latest price if you would like to buy Manganese Dioxide MnO2 in bulk.

Product Performance of Manganese Dioxide MnO2 CAS 1313-13-9:
Physical properties: black amorphous powder, or black rhombic crystals. Solubility: Difficult to dissolve in water, weak acid, weak base, nitric acid, cold sulfuric acid, and dissolve in concentrated hydrochloric acid under heating to produce chlorine gas.

Chemical properties: Manganese dioxide is an amphoteric oxide. There is a corresponding salt in the form of a perovskite structure such as BaMnO3 or SrMnO3 (obtained by a compound reaction in a molten alkali system). There is also manganese tetrachloride.

When meeting the reducing agent, it shows an oxidizing property. If manganese dioxide is placed in a stream of hydrogen and heated to 1400K to obtain manganese oxide; manganese dioxide is heated in a stream of ammonia to obtain brown-black manganese trioxide; reacting manganese dioxide with concentrated hydrochloric acid produces l chloride Manganese chloride, chlorine and water.

When it meets strong oxidants, it also shows reducing property. It is a strong oxidant in an acid medium.

Manganese Dioxide Composition:

MnO2H2OFeCuPbNiCoHgAcid insolublesulfate
92.33%2.17%65ppm0.5ppm0.5ppm2.0ppm2.0ppm47ppm0.01%1.2%


How is Manganese Dioxide MnO2 produced?
Naturally occurring manganese dioxide contains impurities and a large amount of manganese trioxide. Only a limited number of deposits contain gamma modifiers of sufficient purity to meet the needs of the battery industry.

The production of batteries and ferrites (the two main uses of manganese dioxide) requires high-purity manganese dioxide. The battery needs "electrolytic manganese dioxide", and the ferrite needs "chemical manganese dioxide".
1. Chemical Manganese Dioxide
One method is to start with natural manganese dioxide and then use dinitrogen tetroxide and water to convert it into a solution of manganese (II) nitrate. The evaporation of water leaves crystallized nitrates. At a temperature of 400°C, the salt decomposes, releasing N2O4 and leaving a pure manganese dioxide residue. These two steps can be summarized as:
MnO2 +N2O4⇌MnNO32

2. Carbothermal reduction of manganese dioxide
In another method, manganese dioxide is carbothermal reduced to manganese (II) oxide dissolved in sulfuric acid. The filtered solution was treated with ammonium carbonate to precipitate MnCO.
The carbonate is calcined in air to obtain a mixture of manganese (II) and manganese (IV) oxides. To complete the process, the suspension of the material in sulfuric acid is treated with sodium chlorate. The chloric acid formed in situ can convert any Mn(III) and Mn(II) oxides into carbon dioxide, releasing chlorine by-products.

3. Manganese epoxide and manganese monoxide
The third method involves manganese epoxide and manganese monoxide. The two reagents are mixed in a ratio of 1:3 to form manganese dioxide:
Mn2O7 + 3 MnO→5 MnO2
Finally, the effect of potassium permanganate on manganese sulfate crystals produces the desired oxide.
2 KMnO4 + 3 MnSO4 + 2 H2O→5 MnO2 + K2SO4 + 2 H2SO4

4. Electrolytic Manganese Dioxide
Electrolytic manganese dioxide (EMD) is used in zinc-carbon batteries together with zinc chloride and ammonium chloride. EMD has also commonly used in manganese zinc dioxide rechargeable alkaline (Zn RAM) batteries. For these applications, purity is critical. The production method of EMD is similar to the production method of electrolytic ductile pitch (ETP) copper: manganese dioxide is dissolved in sulfuric acid (sometimes mixed with manganese sulfate) and electricity is applied between the two electrodes. The dissolved MnO2 enters the solution in the form of sulfate and is deposited on the anode.

Applications of Manganese Dioxide MnO2:
Manganese dioxide is a black or brown solid, naturally present in the mineral pyrolusite, which is the main ore of manganese and manganese nodules.

The main use of MnO2 is for dry batteries, such as alkaline batteries and zinc-carbon batteries.

MnO2 is also used as a precursor for pigments and other manganese compounds (such as KMnO4). It is used as a reagent in organic synthesis, for example for the oxidation of allyl alcohol.

MnO2 is used as a depolarizer for dry batteries, as a catalyst and oxidant in the synthesis industry, and as a colorant, decolorant and iron removal agent in the glass industry and enamel industry.

MnO2 is used to manufacture metallic manganese, special alloys, ferromanganese castings, gas masks and ferrites for electronic materials.

MnO2 can be used in the rubber industry to increase the viscosity of rubber.

MnO2 is used as a catalyst in chemical experiments

Used as a catalyst for the decomposition of hydrogen peroxide (hydrogen peroxide) to produce oxygen.

Used as a catalyst when heating potassium chlorate to decompose and produce oxygen.

It reacts with elemental aluminum powder to produce manganese by a thermite reaction.

Use pigments, yellow glass, etc.

React with hot concentrated hydrochloric acid to produce chlorine.

It reacts with molten caustic potassium (potassium hydroxide) in the air to produce potassium manganate.

In the decomposition reaction of potassium permanganate, manganese dioxide acts as a self-catalyst for potassium permanganate.

Storage Condition of Manganese Dioxide MnO2 Powder:
Precautions for storage: Store in a cool, ventilated warehouse. Keep away from fire and heat. It should be stored separately from combustibles (combustibles), reducing agents and acids, and avoid mixed storage. The storage area should be equipped with suitable materials to contain the leakage.

Packing & Shipping of Manganese Dioxide MnO2 Powder:
We have many different kinds of packing which depends on the Manganese Dioxide MnO2 Powder quantity.
Manganese Dioxide MnO2 Powder packing: vacuum packing, 1kg/bag, 25kg/barrel, or as your request.
Manganese Dioxide MnO2 Powder: could be shipped out by sea , by air, by express as soon as possible once payment receipt.

Manganese Dioxide Properties

Other Names manganese oxide, MnO2 powder
CAS No. 1313-13-9
Compound Formula MnO2
Molecular Weight 86.94
Appearance Black Powder
Melting Point 535 °C
Boiling Point N/A
Density 5.03 g/cm3
Solubility in H2O Insoluble
Exact Mass 86.9279
   
   

Manganese Dioxide Health & Safety Information

Signal Word Warning
Hazard Statements H302 + H332
Hazard Codes Xn, O
Risk Codes N/A
Safety Statements N/A
Transport Information NONH


The tungsten rod is a rod-shaped material made from tungsten, which has advantages such as good density, high melting point, good thermal conductivity, and corrosion resistance. It is widely used in manufacturing various high-temperature heating equipment and high-precision components.Basic characteristics of tungsten rodsHigh density: The density of tungsten rods is 19.35g/cm3, one of the highest densities among metal materials. Its high-density characteristics make tungsten rods less prone to deformation and warping during manufacturing, ensuring their structural stability and reliability.High melting point: The melting point of tungsten rods is as high as 3410 ℃, which can maintain good stability at high temperatures and will not melt or decompose. This characteristic enables tungsten rods to have excellent thermal stability and corrosion resistance in high-temperature environments and is widely used in high-temperature heating equipment and pipelines.Good thermal conductivity: Tungsten rods have good thermal conductivity, which can quickly transfer heat to surface of heating elements, thereby improving heating efficiency.Corrosion resistance: Tungsten rods are not easily oxidized or corroded in high-temperature environments and can resist various chemical corrosion.Application fields of tungsten rodsIndustrial field: In the industrial field, tungsten rods are widely used to manufacture high-temperature heating equipment, high-temperature pipelines, chemical equipment, etc. In addition, tungsten rods can also be used to manufacture high-precision electronic components and components, such as circuit boards, connectors, etc.In architecture, tungsten rods are mainly used for structural support and decoration. Due to its high density, strength, and corrosion resistance, tungsten rods can manufacture high-level bridges, support structures for high-rise buildings, and more. At the same time, the luxurious texture and elegant colors of tungsten rods also make them excellent decorative materials for high-end buildings.Medical field: In the medical field, tungsten rods are widely used in producing surgical instruments, implants, and orthotics due to their non-toxic and non-radioactive characteristics. In addition, tungsten rods can also be used to make high-precision and corrosion-resistant laboratory and diagnostic equipment.Production process of tungsten rodsThe production process of tungsten rods mainly includes processes such as batching, forging, and heat treatment. The specific process is as follows:Ingredients: Select appropriate metal raw materials for ingredients according to product requirements.Forging: Heat the ingredients before forging, and strictly control the temperature and deformation to ensure stable product performance.Heat treatment: Heat treats the forged product to eliminate internal stress and improve its mechanical properties.Other processing: Surface treatment, mechanical processing, etc., according to product requirements.Future development direction of tungsten rodsWith the continuous progress of technology and the increasing demand for applications, the future development of tungsten rods will mainly focus on the following aspects:High performance: To meet the demand for high-performance materials in different fields, the physical, chemical, and mechanical properties of tungsten rods are improved by changing their composition, microstructure, and processing technology. For example, by adding trace elements or using special processing techniques, tungsten rods' high-temperature strength, hardness, or corrosion resistance can be improved.Environmental protection: With the improvement of environmental awareness, more attention will be paid to the environmental pollution problem during the production of tungsten rods. Develop environmentally friendly production processes and technologies, reduce environmental pollution loads, and achieve sustainable development. For example, adopting environmentally friendly production processes and equipment to reduce waste gas, wastewater, and slag emissions and improve resource utilization efficiency.Functionalization: Utilizing surface coating, doping, and other technical means, tungsten rods can have specific functional properties and expand their application range. For example, developing tungsten-based biomaterials with antibacterial, antiviral, anti-tumor, and other biological activities will play a greater role in medicine.Composite: Composite with other materials to form composite materials with excellent performance, further improving tungsten rods' application value and effectiveness. For example, by combining tungsten rods with materials such as ceramics and glass, new materials with high-temperature performance and good toughness can be obtained.Intelligentization: By combining modern technology, microelectronic devices such as intelligent sensors and micro actuators are integrated into tungsten rod substrates to achieve intelligent and multifunctional materials. For example, combining microelectronic devices with tungsten rods can create high-temperature electronic components with adaptive capabilities.ConclusionIn short, as a material with broad application prospects, tungsten rods will continue to develop and progress in the future. 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If you are looking for tungsten rods, please send an email to: sales1@rboschco.com
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2023
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Apr 15
2023
cobalt chromium molybdenum alloys are used in the medical industry for applications such as orthopedic implants. Their popularity has waned due to their limited hardness and tribological properties, leading to the development of alternative systems.In orthopaedics, cobalt-chromium-molybdenum alloys have been widely used in hip replacements and other metal-on-metal prostheses because of their high strength. However, complications such as loosening and tissue necrosis have been reported. These have been attributed to the alloy’s biocompatibility.Alloys of this type are manufactured using a range of processing techniques, including casting and wrought forging. Some are fabricated through spark plasma sintering, which results in an alloy with carbide-free microstructures.The influence of chromium and molybdenum content on the phases present in a cobalt-chromium-molybdenum system is investigated through X-ray diffraction (XRD), nanomechanical, and electrochemical behavior. The results indicate that the hardness of the alloys increases in line with the increasing chromium content, and reduces with increasing molybdenum content.In addition, the open-circuit potential, polarization resistivity, and linear sweep voltammetry disclose that passivity improves in line with the increasing Cr content, whereas reduced modulus demonstrates an inflection at 30 wt% of Cr. These findings are in agreement with previous research on the metallurgical properties of cobalt-chromium-molybdenum systems.Cobalt-based alloys possess many desirable properties, such as heat resistance (strong at very high temperatures), wear resistance, and corrosion resistance. They are generally categorized into softer and harder grades, based on the crystallographic nature of cobalt (its sensitivity to stress), the solid-solution-strengthening effects of chromium, tungsten, and molybdenum, the formation of metal carbides, and the corrosion resistance imparted by chromium. The softer and tougher compositions are usually employed in high-temperature applications such as gas turbine vanes and buckets, while the more rigid grades are used to withstand wear and tear.
Apr 15
2023
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