Name | Sodium Tungstate Dihydrate |
Synonyms | SODIUM TUNGSTATE 2H2O Sodiumtungstatedihydrate SODIUM TUNGSTATE-2-HYDRATE TUNGSTIC ACID NA-SALT 2H2O SODIUM TUNGSTATE DIHYDRATE Sodium Tungstate Dihydrate SODIUM TUNGSTATE(VI) DIHYDRATE Tungsticaciddisodiumsaltdihydrate TUNGSTIC ACID SODIUM SALT DIHYDRATE |
CAS | 10213-10-2 |
EINECS | 600-275-2 |
InChI | InChI=1/2Na.2H2O.4O.W/h;;2*1H2;;;;;/q2*+1;;;;;2*-1;/r2Na.O4W.2H2O/c;;1-5(2,3)4;;/h;;;2*1H2/q2*+1;-2; |
InChIKey | WPZFLQRLSGVIAA-UHFFFAOYSA-N |
Molecular Formula | H4Na2O6W |
Molar Mass | 329.85 |
Density | 4.18 |
Melting Point | 698°C(lit.) |
Water Solubility | 730 g/L (20 ºC) |
Solubility | Soluble in water, insoluble in alcohol, slightly soluble in ammonia. |
Appearance | White crystal |
Specific Gravity | 3.25 |
Color | White to slightly yellow |
Odor | Odorless |
Exposure Limit | ACGIH: TWA 3 mg/m3NIOSH: TWA 1 mg/m3; STEL 3 mg/m3 |
Maximum wavelength(λmax) | ['λ: 260 nm Amax: ≤0.120', , 'λ: 280 nm Amax: ≤0.035'] |
Merck | 14,8698 |
PH | 9.5-11.5 (25℃, 1M in H2O) |
Storage Condition | Store at +15°C to +25°C. |
MDL | MFCD00149190 |
Physical and Chemical Properties | Properties of colorless crystals or white orthorhombic crystals. melting point 698 ℃ relative density 3.25 solubility soluble in water, slightly alkaline. Insoluble in ethanol, slightly soluble in ammonia. |
Use | Used in the manufacture of metal tungsten, tungstic acid, tungstate, dyes, inks, catalysts, etc |
Hazard Symbols | Xn - Harmful |
Risk Codes | R22 - Harmful if swallowed R36/38 - Irritating to eyes and skin. R36 - Irritating to the eyes |
Safety Description | S36 - Wear suitable protective clothing. S37/39 - Wear suitable gloves and eye/face protection S26 - In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. S39 - Wear eye / face protection. |
WGK Germany | 1 |
RTECS | YO7900000 |
TSCA | Yes |
HS Code | 28418000 |
Toxicity | LD50 (mg tungstate/kg) in rabbits: 105 i.m.; in rats: 240 s.c. (Venugopal, Luckey) |
Raw Materials | Sodium hydroxide Hydrochloric acid |
Downstream Products | Light Fast Violet Lake |
Reference Show more | 1. Lu, Jun, et al. "Evaluation of antioxidant and antibacterial properties of extracts from Trollius chinensis Bunge." European Food Research and Technology 240.2 (2015): 301-310.https://doi.org/10.1007/s00217-014-2329-2 2. [IF=4.452] Onome Ejeromedoghene et al."Intrinsic structural/morphological and photochromic responses of WO3 co-doped MoO3 nanocomposites based on varied drying methods."Drying Technology. 2021 Jul 21 |
colorless crystal or white crystalline powder. Melting point 665 C; d 3.23. Can stroke in dry air. Soluble in about 1.1 parts of water, the solution is weak alkaline, pH 8~9. Insoluble in alcohol and acid. Loss of water of crystallization at 100 °c.
excess tungstic acid was added to sodium hydroxide solution, heated, stirred and filtered, the filtrate was concentrated until crystals were precipitated, cooled and filtered to obtain pure sodium tungstate.
Analytical reagents for serum protein, protein-free serum filtrate, Alkaloid precipitation. It is also used in the manufacture of metal tungsten, tungstic acid and tungstate. It can also be used as mordant, pigment and catalyst, fabric fire retardant, etc.
rabbit intramuscular LDso:105mg (tungstate)/kg; Rat subcutaneous LD50: 240mg (tungstate)/kg. Should be stored in a cool, dry warehouse. Do not break the drum and keep the packaging intact. Pay attention to moisture. It should not be stored and mixed with acids, and should be protected against rain and sunlight during transportation.
pH indicator color change ph range | 9 - 11.5 at 100g/l at 20 c |
EPA chemical information | Information provided by: ofmpub.epa.gov (external link) |
toxicity | sodium tungstate is more toxic than other compounds of tungsten. Its allowable concentration is lmg/m3. For others, see tungsten trioxide. |
use | used in the manufacture of metal tungsten, tungstate and tungstate. Used as mordant, pigment and catalyst. It can also be used as fabric fire retardant and analytical chemical reagents. This product is used as a fabric additive, and a mixture composed of sodium tungstate, ammonium sulfate and ammonium phosphate is used for fireproof and waterproof of fibers. This fiber can be used to make fireproof rayon and rayon. It can also be used for fabric weighting, leather tanning, and electroplating coating anti-corrosion. This product is used as a cosolvent to introduce enamel coloring material to reduce firing temperature and complement color. It is mainly used in the manufacture of metal tungsten, tungstate and tungstate, as well as dyes, pigments, inks, electroplating, etc. It is also used as a fire retardant for fabrics and cellulose, catalysts, etc. Electroplating grade and catalyst must be selected for analytical purity. |
production method | 1. soda sintering process: tungsten concentrate is ground through a 180 mesh sieve by soda sintering method. Ingredients according to the following proportions: WO 320% ~ 22%, soda is about 1.15 times the theoretical amount, saltpeter is 1% ~ 4% of tungsten ore amount. The prepared materials are evenly mixed and then sent to a sintering furnace for sintering at 800~900 ℃. Smelting for 2~3 h, condensing, crushing, and sending to the extractor. Heating softened water, leaching, filtering with a cylinder filter, the filtered solution is purified, concentrated, crystallized, and dehydrated to obtain the product. The scheelite is ground and pulped with water by the soda-soluble hydraulic boiling method of tungsten concentrate, then the scheelite is fed into a pressure boiler and then soda with an excess of 1.5 times the theoretical amount is added. After charging, the scheelite is heated to 200~225 ℃ under stirring and decomposed for 4 hours. The extract is filtered, the filtrate is injected into the purifier, after impurity removal treatment, and then injected into the evaporator for concentration. Cooling the crystallized product. 2. Caustic soda solution decomposition method pulverizes the roasted wolframite concentrate through a 320 mesh sieve. Use a belt to convey it to the hopper for measurement and then add it to the alkali cooking pot. Add water and stir, and add 35% NaOH solution dropwise at 80~90 ℃. The mass ratio of concentrate to lye is 1: (1.5~2.0). After dropping, boil at 0.1~0.15 MPa for about 4 hours. Let stand, the slurry is clarified and filtered. After the filtrate is injected into the purifier for impurity removal treatment, it is concentrated in the evaporator. Cooling crystallization dehydrated product. The tungsten ore alkaline hydrolysis method pulverizes wolframite to 320 mesh, and is added to the 30% caustic soda for alkaline hydrolysis. After alkaline hydrolysis, it reacts with calcium chloride to synthesize calcium tungstate, and calcium tungstate reacts with hydrochloric acid to generate Tungstate, then reacts with caustic soda to form sodium tungstate, which is evaporated and crystallized, centrifuged and dehydrated, and dried to obtain the finished product of sodium tungstate. Its MnWO4?FeWO4 + 4NaOH → 2Na2WO4 + Fe(OH)2?Mn(OH)2Na2WO4 + CaCl2 → CaWO4 +2NaClCaWO4 + 2HCl → CaCl2 + H2WO4H2WO4 + 2NaOH → Na2WO4?2H2O |