Tungsten trioxide is yellow powder, insoluble in water, soluble in alkali, slightly soluble in acid, it is used to produce high melting point alloy, tungsten filament and fire proofing material. It can be made by tungsten ore and alkali through melting together with acid.
EINECS Number 215-231-4;
Appearance: Yellow powder；
Solubility：Insoluble in water, soluble in alkali, slightly soluble in acid.
Chemicle property: Significant sublimation at 850 ℃. Almost no reaction with inorganic acid and hydrofluoric acid, can slowly dissolved in ammonia and concentrated alkali solution. React with chlorine into chlorine oxides, but does not react with bromine, iodine.
Structure: it depends on temperature. Under 740 degree celsius, it is tetragonal, 330-740 degree celsius it is orthorhombic, 17-330 degree celsius it is monoclinic, -50-17 degree celsius it is triclinic.
Application: Tungsten oxide is mainly used to produce tungsten powder and tungsten carbide powder, which is then used to produce pure tungsten, tunsten filament and tungsten bar, tungsten electrode, radiation shielding material. In industry field it is used for colored agent for yellow ceramics. In shipbuilding industry, tungsten oxide is used as an important anti-corrosion paint and coatings materials.
Health Hazards：Low toxicity. Eyes, skin irritation. Tungsten steel smelting workers systemic weakness, fever, measles-like rash, proteinuria, may be inhaled and smelting of tungsten trioxide related.
Skin contact：Remove contaminated clothing, rinse with plenty of water.
Eye contact: Did eyelid, with the flowing water or saline. Medical treatment.
Inhalation: Remove to fresh air. Keep the respiratory tract open. If breathing is difficult, give oxygen. If breathing stops, artificial respiration immediately and consult a doctor immediately.
Ingestion: Drink enough water, the symptoms and seek immediate medical attention.
Hazardous characteristics: With halogen compounds such as bromine pentafluoride, chlorine trifluoride react violently.
Hazardous combustion products: Harmful toxic fumes.
Fire fighting methods: Firefighters must wear body fire suits. Try to move containers to empty area. Then select the appropriate extinguishing agent.