Name | Chromium(III) sulfate hydrate |
Synonyms | C.I. 77305 CHROMAL(TM) CHROME SULFATE CHROMIC SULFATE Chromic sulfate Chromium sulfate CHROMIUM SULFATE CHROMIC SULPHATE CHROMIUM SULPHATE CHROMIUM(+3)SULFATE chromium(2+) sulfate CHROMIUM(III) SULFATE Chromium(III) sulfate Chromium(III) sulfate hydrate trichromic disulfate hexahydrate |
CAS | 10101-53-8 10031-37-5 |
EINECS | 233-253-2 |
InChI | InChI=1/Cr.H2O4S/c;1-5(2,3)4/h;(H2,1,2,3,4)/q+3;/p-2 |
Molecular Formula | Cr2O12S3 |
Molar Mass | 392.18 |
Density | 3.012 |
Melting Point | 90℃ |
Boling Point | 330℃ at 760mmHg |
Water Solubility | insoluble H2O, acids [MER06] |
Appearance | Crystalline |
Storage Condition | Room Temprature |
Stability | Stable. |
Sensitive | Easily absorbing moisture |
MDL | MFCD00016039 |
Physical and Chemical Properties | Chromium sulfate is an inorganic compound with the chemical formula Cr2(SO4)3. Chromium sulfate hydrate often exists in the form of [Cr(H2O)6]3, which appears purple in appearance, and the aqueous solution turns green by heating. ①cr2 (SO4)3=392.18, purple powder, relative density 3.01. ② Cr2(SO4)3 · 6H2O = 500.25, dark green crystal. ③ Cr2(SO4)3 · 15H2O = 662.41, purple scale crystal. The relative density of 1.87(17/4 deg C), heat to 100 deg C lost very daughter crystal water. ④ Cr2(SO4)3 · 18H2O = 716.45, blue-purple cubic crystal. A relative density of 1.70(22/4 °c), with loss of 12 molecules of crystal water at 100 °c. Soluble in water, slightly soluble in ethanol. after reacting chromium hydroxide with sulfuric acid, it is obtained by natural evaporation and crystallization. chromium sulfate is widely used as mordant for tanning or textile, and in the preparation of chrome alum. It is also used as an analytical reagent, a mordant, and a raw material for making green inks, green paints, ceramic glazes, and other chromium salts, such as chromium trioxide. |
Use | For printing, ceramics, leather and other industries |
Safety Description | S24/25 - Avoid contact with skin and eyes. |
UN IDs | UN 9100 |
Toxicity | MLD in frogs, mice, rabbits (mg/kg): 37, 246.8, 215 i.v. (Cavalli) |
Raw Materials | Sulfuric acid Sodium Dichromate |
EPA chemical information | Information provided by: ofmpub.epa.gov (external link) |
Preparation method | Chromium sulfate is reduced from chromium salt and sulfur dioxide, but there are still other methods. Chromium sulfate hydrate can be made by reacting trivalent chromium oxide, such as chromium trioxide and sulfuric acid. Cr2O3 3 H2SO4 → Cr2(SO4)3 3 H2O chromium sulfate can also be prepared by the reduction reaction of dichromate. the most common way is to form chromium sulfate by the reaction of potassium dichromate and hydrogen sulfide. the side substances are potassium sulfate and water: 4 K2Cr2O7 13 H2SO4 3 H2S → 4 Cr2(SO4)3 4 K2SO4 16 H2O ethanol can also be used instead of hydrogen sulfide, the difference is that in addition to producing chromium sulfate and potassium sulfate, acetic acid and water are also produced. 2 K2Cr2O7 8 H2SO4 3 C2H5OH → 2 Cr2(SO4)3 2 K2SO4 3 CH3COOH 11 H2O However, regarding the above reaction, the obtained chromium sulfate contains crystal water (ie hydrated chromium sulfate). To remove crystal water, CO2 flow at 280 ℃ can be used for dehydration. |
solubility in water (g/100ml) | dissolved grams per 100ml of water: 220g/20 ℃ |
Use | Used in printing and dyeing, ceramics, insoluble gels, and manufacturing chromium-containing catalysts, tanning, paints and inks Used as analytical reagents and mordants Used in printing, ceramics, leather and other industries |
production method | 1. under constant stirring, add a theoretical amount of sulfuric acid with a density of 1.61 to chromium hydroxide and stand at 70 ℃, stir occasionally, and sometimes supplement the evaporated water. after 2~3 times, filter while hot, evaporate and concentrate the filtrate to syrup, and coat it on the glass plate (1kg/m2), evaporate and dry at 800 ℃. |
category | toxic substances |
toxicity classification | highly toxic |
acute toxicity | vein-mouse LDL0: 85 mg/kg |
flammability hazard characteristics | non-combustible substances; thermal decomposition of toxic chromium and sulfur oxide fumes |
storage and transportation characteristics | warehouse is low temperature, ventilated and dry; Fire prevention; Store separately from strong oxidant |
fire extinguishing agent | water, carbon dioxide, dry powder, sand |
occupational standard | TWA 0.5 mg (chromium)/m3 |
toxic substance data | information provided by: pubchem.ncbi.nlm.nih.gov (external link) |