Identification of potassium iodide CAS Registry Number 7681-11-0

Identification of potassium iodide CAS Registry Number 7681-11-0

Physical property:

Properties: colorless crystal, belonging to cubic crystal system. Odorless, with a strong bitter and salty taste.

Density (g/ml 25oC): 3.13

Melting point (OC): 681

Boiling point (OC, atmospheric pressure): 1420

Refractive index (n20/d): 1.677

Flash point (OC,): 1330

Vapor pressure (kPa, 25oC): 0.31 mm Hg

Solubility: easy to deliquesce in wet air. When exposed to light and air, free iodine can be separated out and turn yellow, which is easier to turn yellow in acidic aqueous solution. It is easily soluble in water and absorbs heat significantly when dissolved. It is soluble in ethanol, acetone, methanol, glycerol and liquid hydrogen, and slightly soluble in ether.

Function and use:

1. when exposed to light or placed in the air for a long time, it can precipitate free iodine and turn yellow. It is easier to oxidize and turn yellow in acidic aqueous solution.

2. it turns yellow more easily in acidic aqueous solution. Potassium iodide is the cosolvent of iodine. When dissolved, it forms potassium triiodide with iodine, and the three are in equilibrium.

3. potassium iodide is a permitted food iodine fortifier, which can be used in infant food according to Chinese regulations. The dosage is 0.3-0.6mg/kg. It can also be used for table salt. The dosage is 30-70ml/kg. As a component of thyroxine, iodine participates in the metabolism of all substances in livestock and poultry and maintains the internal heat balance. It is an essential hormone for the growth and reproduction of livestock and poultry. It can improve the growth performance of livestock and poultry and promote the health of the body. If the body of livestock and poultry is deficient in iodine, it will lead to metabolic disorders, body disorders, goiter, affect nerve function, skin color and feed digestion and absorption, and eventually lead to slow growth and development

It is easily soluble in water and absorbs heat when dissolved. The solubility in 100g water is 127.5g (0 ℃), 144g (20 ℃), 208g (100 ℃). In case of wet air and carbon dioxide, it will decompose and turn yellow. Soluble in methanol, ethanol and glycerol. Iodine is easily soluble in an aqueous solution of potassium iodide. It is reductive and can be oxidized by oxidizing agents such as hypochlorite, nitrite and ferric ions to release free iodine. It decomposes when exposed to light, so it should be stored in a sealed, dark and cool place. In addition to being used for medicine and photography, it is also used as an analytical reagent.

Properties and stability:

1. potassium iodide is often used as corrosion inhibitor for steel pickling or synergist of other corrosion inhibitors. Potassium iodide is the raw material for preparing iodide and dye. It is used as photographic emulsifier, food additive, expectorant and diuretic in medicine, medicine for prevention and treatment of goiter and hyperthyroidism before operation, and analytical reagent. Used in photographic industry as photosensitive emulsifier, also used as medicine and food additives.

2. used as feed additive. Iodine, as a component of thyroxine, participates in the metabolism of all substances in livestock and poultry and maintains the heat balance in the body. Iodine is an essential hormone for the growth, reproduction and lactation of livestock and poultry. It can improve the growth performance of livestock and poultry and promote the health of the body. If the body of livestock and poultry is deficient in iodine, it will lead to metabolic disorders, body disorders, goiter, affect nerve function, digestion and absorption of coat color and feed, and eventually lead to slow growth and development.

3. the food industry uses it as a nutritional supplement (iodine fortifier). It can also be used as feed additive.

4. used as analytical reagent, such as preparing iodine standard solution as auxiliary reagent. It is also used as photosensitive emulsifier and feed additive. Used in pharmaceutical industry.

5. potassium iodide is the cosolvent of iodine and some insoluble metal iodides.

6. potassium iodide has two main uses in surface treatment: first, it is used for chemical analysis. It uses the medium reducibility of iodine ions and some oxidizing ions to react to produce simple iodine, and then calculates the concentration of the tested substance through the determination of iodine; Second, it is used for complexing some metal ions. Its typical use is as a complexing agent for cuprous and silver in electroplating copper silver alloy.

Synthetic method:

1. at present, formic acid reduction method is mostly used to produce potassium iodide in China. That is, potassium iodide and potassium iodate are produced by the interaction of iodine and potassium hydroxide, and then potassium iodate is reduced by formic acid or charcoal. However, iodate is produced in this method, so the product should not be used as food additive. Food grade potassium iodide can be produced by iron filings method.

Storage method:

1. it shall be stored in a cool, ventilated and dark warehouse. It shall be protected from rain and sun during transportation.

2. handle with care during loading and unloading. Vibration and impact are strictly prohibited. In case of fire, sand and carbon dioxide fire extinguishers can be used.

Toxicology data:

Acute toxicity: ld50:4000mg/kg (oral administration to rats); 4720mg/kg (rabbit percutaneous).

Lc50:9400mg/m3, 2h (mouse inhalation)

 
Ecological data:

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

Molecular structure data:

1. Molar refractive index: 23.24

2. Molar volume (m3/mol): 123.8

3. Isotonic specific volume (90.2k): 247.0

4. Surface tension (dyne/cm): 15.8

5. Polarizability (10-24cm3): 9.21

Calculate chemical data:

1. Reference value for hydrophobic parameter calculation (xlogp): 2.1

2. Number of hydrogen bond donors: 0

3. Number of hydrogen bond receptors: 6

4. Number of rotatable chemical bonds: 3

5. Topological molecular polarity surface area (TPSA): 9.2

6. Number of heavy atoms: 10

7. Surface charge: 0

8. Complexity: 107

9. Number of isotope atoms: 0

10. Determine the number of atomic structure centers: 0

11. Number of indeterminate atomic stereocenters: 1

12. Determine the number of chemical bond conformation centers: 0

13. Number of indeterminate chemical bond conformation centers: 0

14. Number of covalent bond units: 1