Iodine CAS: 7553-56-2 Basic information
|Synonyms:||IodineFlakes,99.998%;Iodine,Resublimed,99.5%;Iodine(Resublimed)ExtraPure;Iodine, 99+%;NLT99,5%orrefined;Iodinespheres,ultradry,-60mesh,99.999%(metalsbasis);Iodine, 0.1 N standard solution;Iodine, for analysis ACS, 99.8+%|
|Product Categories:||Pharmaceutical Intermediates;IodinationPharmacopoeia (USP);Pharmacopoeial Antibiotics;Pharmacopoeia A-ZPharmacopoeia (USP);IodinationEssential Chemicals;Reagent Plus;Analytical Reagents for General Use;E-L, Puriss p.a. ACS;Puriss p.a. ACS;ACS GradeSynthet|
Iodine CAS: 7553-56-2 Chemical Properties
|density:||1.32 g/mL at 25 °C|
|Melting point:||113 °C(lit.)|
|Boiling point:||184 °C(lit.)|
|storage temp.:||Store at RT.|
|Water Solubility:||0.3 g/L (20 ºC)|
|NIST Chemistry Reference:||Iodine(7553-56-2)|
|PH:||5.4 (H2O)(saturated solution)|
|vapor pressure:||0.31 mm Hg ( 25 °C)|
|vapor density:||9 (vs air)|
|Odor:||Sharp, characteristic odor|
|CAS DataBase Reference:||7553-56-2(CAS DataBase Reference)|
|EPA Substance Registry System:||Iodine (7553-56-2)|
Item of analysis
Result of analysis
Dark brown crystal granule
Loss on Drying
Chlorine and bromine content （%）
重金属（ Heavy metal）
Conclusion： Conform The Standard
|Iodine Usage And Synthesis|
|Element of halogen family||Iodine is the second halogen element which was found after chlorine. Iodine is a non-metallic element in the main group Ⅷ of the periodic table, and the symbol is I. It has radionuclides of 123 iodine, 125 iodine and 131 iodine respectively. Some data about it are as follows: Atomic number 53; atomic weight 126.9044; electronic configuration 2,8,18,18,7; relative density 4.93; melting point 113.5 ℃and boiling point 184 ° C. The common oxidation states of iodine in the compounds are-I (iodide), + Ⅴ (iodate), + Ⅶ (periodate). Iodine is a shiny crystal with the color of atropurpureus. It sublimates slowly to obtain gaseous toxic iodine that has a purple color and irritating smell.|
In 1811, French chemist B. Kurtwa found that after extraction of potassium carbonate from the roasted seaweed, the remaining mother liquor added sulfuric acid produced violet steam with heating, and then it condensed into brilliant flaky crystals. The discovery elucidated the physical properties of iodine. The discovery was affirmed by H. David and J.L. Gailusak later, and they pointed out that the new element does exist. J.L. Gailsacker named it iodine which derived from the Greek ioeides, and originally intended as “purple”. The content of iodine in the crust is 3 × 10-5%. There is a small amount of iodide ion in the seawater, and the content is 50mg in 1t seawater. There is a lot of iodine in the seaweed, but iodine is mainly from Chilean nitrate. It exists in the form of NaIO3 and Ca (IO3) 2.
Iodine has the characteristics of metal. Iodate that has been known so far includes iodine iodide, iodic acid perchlorate and iodine acetate and so on. Iodine precipitates in the cathode when iodine acetate solution is electrolyzed, which prove that iodine has positive charge. Iodine is soluble in organic solvents, and the color of solution is purple, the same as gaseous iodine. It is always a diatomic molecule in different polar solvents, such as carbon tetrachloride, trichloromethane and ethane. If dissolved in solvent with a higher polarity, such as water, it was light brown. If dissolved more in ethanol, the color is brown. The different color of the solution is due to the solvation of the solvent molecules combined with iodine with coordination bond. In the solvent with non-polarity or low polarity, solvation doesn’t exist, so the solution color is the same as iodine vapor. Iodine is slightly soluble in water, but soon it hydrolyte. The solution is a weak acid, and the alkali can promote hydrolysis of it. As iodide is very unstable, disproportionation occurs to get iodate and iodide.
|Distribution in nature and ecology||Iodine is widely distributed in nature and it exists in the form of compounds. There are traces of iodine in rocks, soil, water, flora and fauna and air. But in addition to seawater, the distribution of iodine in nature is very uneven.|
The iodine in the environment is present in the form of a compound, and the iodine compound is mostly soluble in water and transferred with the flow of water. The leaching effect of precipitation takes away the iodine in the soil, and it flows into the river and lake, eventually into the sea. Therefore, iodine in seawater is the most abundant and stable. Seawater is known as a "iodine library" with iodine concentration of 50~60μg/L. A portion of the iodine in the sea enters the air through evaporation, with about 400,000 t of iodine entering the atmosphere each year. The iodine lands in the form of rain (snow), which is iodine cycle in the nature.
The content of iodine in rocky soil is up to 9.0mg/kg. Iodine content is low in areas with larger geological tilt angle, inland and leaching effect of precipitation. Iodine content is high in coastal areas and islands. Living creature gets iodine from the nature. After beneficiation, the concentration of iodine in living creature is generally higher than that in natural environment.
|Alexipharmic and antiseptic drug||Iodine has a strong bactericidal effect, and it could kill bacteria spores, fungi, viruses and protozoa. Iodine plays a bactericidal effect mainly in the molecular form (I2). The principle is as follows: iodine has an effect of iodization and oxidization on active group of the bacterial protein, and then it combines with amino group, leading to protein denaturation and inhibiting metabolic enzyme system of bacterial.|
The solubility of iodine in water is very small. But in the presence of iodide, the solubility increased by hundreds of times due to the formation of soluble triiodide compounds. The presence of iodide also helps reduce its volatility. Accordingly, appropriate amount of potassium iodide is added to promote the dissolution of iodine in water in the preparation of iodine solution. There are three components with a bactericidal effect in the aqueous solution of iodine: molecular iodine (I2), triiodide ions (I3-) and hypolodous acid (HIO). Among them, HIO less has the strongest bactericidal effect; and then I2 times; I3-is the most weak.
In acidic conditions, bactericidal effect is strong with increased free iodine. It is opposite in alkaline conditions.
Iodine tincture is the most effective skin disinfectant. In general, 2% iodine tincture is used for skin disinfection, and 5% is for surgical site disinfection. As iodine is a strong irritant on the organization, and intensity is proportional to the concentration, so after a little dry of iodine tincture, we should wipe it with 75% ethanol, preventing blistering, peeling and dermatitis. Iodine glycerol has a small irritation, so it is used for mucosal surface disinfection. 2% iodine solution without ethanol is suitable for superficial skin damage and wound, preventing bacterial infection. In emergency, it is used for disinfection of drinking water. Add 2% iodine tincture 5 to 6 drops to each liter of water. And then we could drink after 15 minutes. The water has no bad smell. And various pathogens, protozoa and other creatures can be killed.
|Toxicity||Iodine vapor irritates the eyes, skin and respiratory organs strongly. Exposure to iodine for a long time or inhalation of iodine vapor will cause cough, snivel, tears, fever, headache, conjunctivitis, parotid gland enlargement, bronchitis, rhinitis, diplopia, stigmata, and blisters in skin and mucous. Severe patents have symptoms of vomiting and diarrhea, with protein and hemoglobin in urine.|
If somebody is being poisoned by iodine vapor, he/she should leave the scene immediately to breathe fresh air outdoor, and then inhale 5% sodium thiosulfate or 2% sodium bicarbonate solution. And then wash the nose, mouth and throat with 2% sodium bicarbonate solution. If there is an eye pain, you should rinse with water, and drop 2 to 3 drops of hydrochloric acid cocaine. If splash iodine on the skin, you should wash it immediately with sodium thiosulfate solution. After oral poisoning, you should drink starch paste, milk, eggs or diluted sodium thiosulfate aqueous solution quickly.
The maximum concentration of iodine allowable in the air is 1 mg/m3. Production equipment should be closed, and production environment should also be well ventilated. Workers must wear closed protective glasses, long boots, latex gloves, gas masks and overalls.