What Is Potassium Chromium?

Chromium potassium sulfate was used as an analytical reagent. Used as a hardening agent for photographic film in photographic fixing solution, used as a chromium complexing agent and mordant for printing and dyeing when producing dyes such as reactive red brown K-B3R, neutral violet BL, neutral orange RL and neutral peach red BL . Also used in glass, ceramics and other fields. Cross-linking agent for oil fracturing fluid, tanning agent, mordant, photographic fixing agent, food additive, etc.

Chinese name: Chromium potassium sulfate

Chinese alias: Chromium potassium sulfate, twelve water; Chromium (III) potassium sulfate dodecahydrate;

English name: Chromium potassium sulfate dodecahydrate

English aliases: potassium, chromium (3+), disulfate, dodecahydrate

CAS number: 7788-99-0

Molecular formula: CrH ₂₄ KO ₂₀ S ₂

Molecular weight: 499.40300

Exact mass: 498.93400

PSA: 288.04000 ^[1]

S26In case of contact with eyes, rinse immediately with plenty of water and seek medical advice.

After accidental contact with eyes, rinse immediately with plenty of water and seek medical advice.

S37 / 39Wear suitable gloves and eye / face protection

Wear appropriate gloves and goggles or a mask. ^[1]

R36 / 38Irritating to eyes and skin.

Irritates eyes and skin.

Quality inspection items	Project indicator value
Content [CrK (SO4) 2 · 12H2O]	99.5%
Ammonium salt (NH4)	0.01%
Water insoluble matter	0.005%
Heavy metals (as Pb)	0.002%
Aluminum (Al)	0.02%
Iron (Fe)	0.005%
Chloride (Cl)	0.002%

Packed in iron drums lined with polyethylene plastic bags, net weight 50kg per barrel; packed in plastic woven bags lined with polyethylene plastic bags, net weight 40kg each It should be stored in a cool, ventilated and dry warehouse. The packaging should be sealed, and moisture and weathering should be prevented. Do not co-storage with edible items, flammable items and acids. Protect from rain and direct sunlight during transportation. Handle with care when loading and unloading to prevent damage to the packaging. ^[1]

CAS number: 7788-99-0

MDL number: MFCD00149917

EINECS number: 233-401-6

RTECS number: GB6850000

PubChem number: 24881803 ^[1]

1. Properties: purple or amethyst red octahedral crystal

2. Density (g / mL 25ºC): 1.826

3. Melting point (ºC): 89

4. Solubility (mg / mL): soluble in water: 24g / 100mL (15ºC), dilute acid. Insoluble in alcohol ^[1]

If sodium dichromate solution or powder is splashed on the skin, immediately rinse it with plenty of water. The maximum allowable concentration in the air is 0.01mg / m ³ . Above this concentration, inhalation can cause ulceration of the nasal mucosa. ^[1]

It is slightly harmful to water. Do not discharge materials into the surrounding environment without government permission.

1. Hydrophobic parameter calculation reference value (XlogP): None

2.Number of hydrogen-bonded donors: 12

3.Number of hydrogen bond acceptors: 20

4.Number of rotatable chemical bonds: 0

5.Number of tautomers: none

6. Topological molecular polar surface area 189

7.Number of heavy atoms: 24

8.Surface charge: 0

9.Complexity: 62.2

10.Number of isotope atoms: 0

11. Determine the number of atomic stereocenters: 0

12. Uncertain number of atomic stereocenters: 0

13. Determine the number of chemical bond stereocenters: 0

14. Uncertain number of chemical bond stereocenters: 0

15. Number of covalent bond units: 16 ^[1]

1. Soluble in 4 parts of cold water and 2 parts of boiling water. Almost insoluble in ethanol. Easily weathered, it is ruby red under transmitted light, and it will turn green when it is heated to 100 ° C and lose part of the crystal water. At 110 ° C, dihydrate is obtained, and at 400 ° C, it becomes anhydrous yellowish green and loses water solubility. Its aqueous solution is purple when cold and green when hot. It is toxic.

2. Soluble in water, the solution is purple when it is cooled, and green when it is hot.

3. It is a purple-red aqueous solution dissolved in water, turns into a green solution when heated to 70 ° C, and turns purple after cooling. Easily absorb moisture and weather in dry air ^[1]

1. Keep the container sealed in a tight container and store in a cool, dry place;

2. Do not co-storage with edible items, flammable items and acids.

3. There is a cover during transportation to prevent sunlight, rain and damage to the packaging. ^[1]

1. Dissolve potassium dichromate in hot water and filter. To the filtrate was added concentrated sulfuric acid, and then ethanol was gradually added. When the liquid turns dark green, continue to add ethanol until no more changes, that is, the end of the reaction. The solution was evaporated, water was added until the relative density of the solution was 1.5, and then the solution was left to crystallize. The crystals were filtered off with suction and dried sufficiently.

2. Add wood chips to potassium dichromate and ammonium sulfate solution, and carry out reduction reaction below 80 ° C. It can be obtained by slow crystallization after standing, solid-liquid separation, washing with a small amount of cold water, and low temperature drying. Alternatively, the sulfur dioxide is passed into a saturated solution of potassium dichromate cooled to 0 ° C, and acidified by adding sulfuric acid.

3. According to the theoretical amount, 15% sulfuric acid aqueous potassium dichromate is used, and the mixed solution is slowly added to the cooled ethanol solution while stirring:

After the reaction was completed, nitric acid with a density of 1.40 was added in an amount of 1/20 of the total volume of the raw materials, and the solution was evaporated until the acetic acid smell completely disappeared. Then add an equal volume of ethanol and mix well. Allow to stand to fully precipitate the crystals of chrome potassium alum. The filtered crystals are dissolved in hot water not exceeding 40 ° C and naturally evaporated in an environment at about 30 ° C to obtain the reagent potassium potassium sulfate. ^[1]

1. Used as tanning agent, printing and mordant and photographic fixing agent.

2. Used as an analytical reagent. Used as a hardening agent for photographic films in photographic fixing solutions, used as a chromium complexing agent and a mordant for printing and dyeing when producing dyes such as reactive red brown K-B3R, neutral violet BL, neutral orange RL and neutral peach red BL . Also used in glass, ceramics and other fields.

3. Crosslinking agent used in oil fracturing fluid, as well as tanning agent, mordant, photographic fixing agent, food additive, etc.

4. Used as analytical reagent. Used as a fixative in microscopic analysis. Used for photo-making.

5. Potassium chromium sulfate is used in trivalent chromium plating and passivation solution. ^[1]

Dangerous Goods Sign: Irritant

Safety identification: S22S24 / 25S37 / S39

Danger sign: R36 / 38