Molecular Formula | O2Sn |
Molar Mass | 150.71 |
Density | 6.95g/mLat 25°C(lit.) |
Melting Point | 1127 °C |
Boling Point | 1800-900°C |
Flash Point | 1800-1900°C |
Water Solubility | INSOLUBLE |
Solubility | Soluble in hot concentrated alkalis, and concentrated acids. Insoluble in alcohol. |
Appearance | White to gray powder |
Specific Gravity | 7 |
Color | White to slightly gray |
Exposure Limit | ACGIH: TWA 2 mg/m3NIOSH: IDLH 100 mg/m3; TWA 2 mg/m3 |
Merck | 14,8778 |
PH | 4-5 (50g/l, H2O, 20℃)(slurry) |
Storage Condition | Store at +5°C to +30°C. |
Stability | Stable. |
Sensitive | 6: forms irreversible hydrate |
Refractive Index | 1.9968 |
MDL | MFCD00011244 |
Physical and Chemical Properties | Character white, light yellow or light gray tetragonal, hexagonal or orthorhombic crystal powder. melting point 1630 ℃ relative density 6.95 solubility insoluble in water, alcohol and aqua regia, soluble in sodium hydroxide, potassium hydroxide. |
Use | Used for enamel and electromagnetic materials, and used in the manufacture of milky glass, tin Salt, porcelain colorant, fabric mordant and weighting agent, steel and glass polishing agent |
Safety Description | S24/25 - Avoid contact with skin and eyes. |
Toxicity | LD50 orally in Rabbit: > 20000 mg/kg |
Raw Materials | Tin Nitric acid |
white, light yellow or light gray tetragonal, hexagonal or orthorhombic crystalline powder. The relative density was 6. 95. Melting point 1630 °c. 1800~1900 degrees C sublimation. Insoluble in water, alcohol and aqua regia, soluble in sodium hydroxide, potassium hydroxide. Electrical conductivity. Heat stable in air.
metal tin nitric acid oxidation method; The washed tin ingot is melted, and then the Tin Flower is exploded by slowly pouring it into cold water with an iron spatula. The tin flowers are slowly added to nitric acid diluted to 20Be for reaction, until no nitric oxide escapes and no tin remains, the reaction solution is clarified, and the upper clear liquid is aspirated and reused, the resulting p-stannic acid was rinsed with boiling water and then washed with deionized water until the iron and heavy metals were analyzed to be acceptable. After dehydration, it was dried at 120 ° C., calcined at 1250 ° C., pulverized and sieved to obtain tin dioxide.
for the manufacture of tin salts. Pigment industry with chromate, lime, vanadium, chlorine, etc., the production of pink, beige, yellow, purple-gold color, used as ceramic, enamel colorants. The glass industry is used as a glass polishing agent and in the manufacture of opalescent glass. It is used as mordant and weighting agent in dyeing and printing industry. It is also used as a catalyst for organic synthesis and in the electronics industry.
packed in a polyethylene plastic bag, the mouth of the bag is tight, and then sealed in an iron drum with a net weight of 25kg per barrel. Store in a ventilated, dry warehouse. It is prohibited to store and transport together with strong acid, strong alkali and edible articles. Prevent moisture and rain. In case of fire, water can be used for rescue. Toxicity and protection: Long-term (15~20 years) by the role of tin dioxide will be suffering from pneumoconiosis, pneumoconiosis. The maximum allowable concentration in air is 10mg/m3 (converted into metal tin). Use anti-virus masks when there is more dust, and pay attention to protect the skin. Attention should be paid to dust and dust.
sublimation point | 1800-1900°C |
EPA chemical information | Information provided by: ofmpub.epa.gov (external link) |
metallic tin | metallic tin is a white glossy malleable metal, belonging to the fourth element of group 14 of the periodic table (the original group Ⅳ A). Tin is the first clear metal element in this family, although it retains some bisexual properties. Its electronic structure has an outer layer of s2p2 electrons ([Kr]4 d105s25p2). This element is very low in abundance in the earth's crust (0.004%), but it is widely distributed, mainly in tin ore (SnO2). As early as the Bronze Age, when ore was used to symbolize wealth, this metal was already known. The ore currently processed contains less than 1% ~ 2% tin, and a considerable amount of concentration work should be done before calcination. The metal is prepared by reducing tin dioxide by carbon: SnO2 C→Sn CO2. Tin is an expensive metal, so (people) take several steps to recover it from tinplate debris. These include chlorination in a dry state to obtain unstable SnCl4, or (using alkaline electrolyte solution) electrolysis method (preparation):Sn 4OH-→ Sn(OH)42-2e-(anode);Sn(OH)42-→ Sn2 +4OH-(cathode);Sn2 + 2e -→ Sn (cathode). Tin does not directly react with hydrogen, but the unstable hydride SnH4 can be prepared by reducing SnCl4. The low stability is due to the very little overlap between the orbital of the tin atom and the orbital of the very small hydrogen atom. Tin forms two oxides: tin monoxide and tin dioxide. These two oxides are both amphoteric, soluble in acid to form divalent tin and tetravalent tin salts, and form stannate and stannate in alkali: SnO + 4OH-→[SnO3]4-+ 2H2O SnO2 + 4OH-→[SnO4]4-+ 2H2O SnO + 4OH-→[SnO3]4-+ 2H2O SnO2 + 4OH-→[SnO4]4-+ 2H2O |
uses and applications | tin dioxide is mainly used as a raw material for enamel, enamel and opal glass. Adding tin dioxide in the glaze making process will significantly enhance the covering ability of the glaze, and can improve the activity and thermal properties of the glaze, so that the color of the fired glaze is white. It is also used as a catalyst for converting carbon monoxide from automobile exhaust into carbon dioxide, a printing and dyeing mordant, a polishing agent for metal and decorative stones, and a raw material for certain fragrances and cosmetics. It can also be used as a carrier for a variety of pigments, mixed with cobalt stannate to make sky blue pigments. Tin dioxide is a good opacifying agent for enamel. It not only has good opacifying properties, but also can obtain fine porcelain surface and better luster. Because tin dioxide is easy to produce stannate during the melting process of enamel, it is applied to grinding and adding in production. The grinding amount is generally 3% ~ 8% of the glaze block. As the raw material of tin dioxide used as an opacifier, the most ideal particle size is not more than 1 μm, the purity should be above 98%, and there should be no metal tin, and the amount of iron (Fe2O3) should be less than 0.1%. Although tin dioxide has good performance and non-toxic properties, it is restricted in use due to the high price of raw materials. Tin dioxide is also the main raw material for making tin-zirconium red pigment (pink pigment). |
preparation method of tin dioxide | strong acid salts of tin, such as tin sulfate, tin tetrachloride, tin nitrate, etc., are hydrolyzed to generate stannic acid or stannic acid, and tin dioxide is generated when burned at 700~800 ℃. This method distilled anhydrous tin tetrachloride. The middle fraction is hydrolyzed and dehydrated to prepare tin dioxide. anhydrous tin tetrachloride is distilled with a Shi Ying distiller, the front distillate lower than 110 ℃ is discarded, and the middle distillate higher than 110 ℃ accounting for 70% of the raw material quantity is collected. Add high-purity ammonia water to the middle distillate until the solution is slightly alkaline, then add a large amount of high-purity water, clarify it after stirring, and pour out the clear liquid. The precipitate was washed with a pouring method until it was free of chloride ions. Heat and dry the precipitate on a water bath, move it to a Shi Ying dish, burn it to a constant amount at a temperature of 800~900 ℃ in a muffle furnace, take it out and cool it to be the finished product. the tin dioxide purified by this method only detected trace amounts of silicon, magnesium, copper and trace amounts of aluminum by spectral qualitative analysis, which is suitable for spectral analysis standard. |
toxicity | LD50 orally in Rabbit: > 20000 mg/kg |
use | for the manufacture of tin salts. The pigment industry is used to cooperate with chromate, lime, vanadium, chlorine, etc. to produce pink, beige, yellow, purple-gold and other colors, which are used as colorants for ceramics and enamels. The glass industry is used as a glass polishing agent and in the manufacture of opal glass. The printing and dyeing industry is used as a fabric mordant and a weightener. It is also used as an organic synthesis catalyst and used in the electronics industry. used in enamel and electromagnetic materials, and used in the manufacture of opal glass, tin salt, porcelain colorant, fabric mordant and weightener, steel and glass polishing agent, etc. used as catalyst, mordant, analytical reagent, also used in the preparation of coatings and electronic industry, etc. preparation of tin salt, catalyst. It is used for enamel pigments, tin salt manufacturing, mordant and weightener for fabrics, polishing agent for marble and glass, and is also a raw material for manufacturing opaque glass, opal glass, catalysts and reagents. High purity 4N grade is mainly used for transparent conductive film, anti-radiation and electrostatic shielding coating and anti-counterfeiting ink. |
production method | metal tin nitric acid oxidation method melts the washed tin ingots, and then slowly pours people with an iron spoon into cold water and bursts them into tin flowers. Then slowly add the tin flower to nitric acid diluted to 20 ° Bé for the reaction, and wait until no nitrogen oxide escapes, and there is no tin remaining. After the reaction solution is clarified, the upper clear liquid is sucked out and reused, and the generated β-Stannic acid is rinsed with boiling water, and then washed with deionized water until the iron and heavy metals are analyzed and dehydrated. Drying at 120 ℃, calcining at 1250 ℃, crushing and sieving to obtain tin dioxide. Its 3Sn 4HNO3 H2O → 3H2SnO3 4NO ↑ H2SnO3[△]→ SnO2 H2O |
toxic substance data | information provided by: pubchem.ncbi.nlm.nih.gov (external link) |