|Company Name:||J & K SCIENTIFIC LTD. |
|Company Name:||Alfa Aesar |
|Sodium nitrite Chemical Properties|
|Melting point ||271 °C(lit.)|
|Boiling point ||320 °C
|density ||1.29 g/mL at 25 °C|
|storage temp. ||2-8°C|
|solubility ||aqueous acid: 1 - 2μl acetic acid per ml H2Osoluble|
|Water Solubility ||820 g/L (20 ºC)|
|Stability:||Stable. Incompatible with reducing agents, strong oxidizing agents, organics and other flammable materials, finely powdered metals. Contact with combustible material may lead to fire. Hygroscopic.|
|CAS DataBase Reference||7632-00-0(CAS DataBase Reference)|
|EPA Substance Registry System||Nitrous acid, sodium salt(7632-00-0)|
|Sodium nitrite Usage And Synthesis|
|Physicochemical property||Chemical formula is NaNO2, in which N has a valency is + III.It is colorless or yellow crystal, the relative density is 2.168 (0℃), the melting point is 271℃, and it is decomposed when 320℃. It is soluble in water, and aqueous solution is alkaline because of nitrate hydrolysis. Sodium nitrite has the characteristics of reduction and oxidation and is mainly oxidation. In acidic solution, the main performance is oxidation. In alkaline solution or in case of strong oxidizing agent, its performance is reduction. With sulfur, phosphorus, organic matter and other friction or impact can cause combustion or explosion. Sodium nitrite can be placed in the air with the oxygen reaction, and gradually produce sodium nitrate: NaNO2+1/2O2=NaNO3.|
When using strong acidic sodium nitrite, it can be nitrited to nitric acid. Nitrite is very unstable, easily decomposed into nitrogen dioxide, nitric oxide and water. The nitrogen atoms and oxygen atoms all have a single pair of electrons, which can be used as ligands, and can be used as ligands to form complexes with many metal ions. Sodium nitrite is toxic, carcinogenic substances, using it must be attention. It is used in printing and dyeing industry and organic synthesis. Sodium nitrite is obtained by the reaction of sodium nitrate and lead in a total of hot condtion.
The reaction mixture obtained by hot water treatment, filtration to remove insoluble lead oxide, concentration and crystallization of sodium nitrite crystal can be obtained.
Figure 1 white sodium nitrite crystal powder
The information of this information is compiled by ChemicalBook Xiao Nan
|Antidote||Sodium nitrite is also a kind of antidote, can make the oxidation of hemoglobin to methemoglobin, and is easy to combine with cyanide ions and produce non-toxic cyanide methemoglobin, then after given sodium thiosulfate, it change into non-toxic sulphur cyanogen compounds, and excreted. The detoxification process is similar to methylene blue. And the effect is stronger than the methylene blue. It keeps for a long time. It is used to save cyanide poisoning.|
[Mechanism] Cyanide and ferric iron (Fe3 +) of mitochondrial cytochrome oxidasewith have high affinity, after making enzyme lost activity, inhibiting cell respiration and causing cells to lactic acidosis and lack of oxygen.This oxidizing agent can make the ferrous iron in hemoglobin (Fe2 +) oxidized to ferric iron (Fe3 +), forming methemoglobin. Iron Fe3+ of methemoglobin MHb and cyanide (CN) combine stronger than Fe3 + of cytochrome oxidaseis. Even if CN- has combined with cytochrome oxidase can also make release again, and recovery of enzyme activity. But after methemoglobin combined with CN - , the formation of the cyanide methemoglobin gradually disintegrate within a few minutes, later release the CN -, and toxicity of cyanide recover. So this product only for cyanide poisoning has a temporary delay its toxicity.This product is to dilate blood vessels.
(1) Severe adverse reactions in injection , should immediately stop drug.
(2) In the treatment of cyanide poisoning, the product with sodium thiosulfate can cause blood pressure to drop, blood pressure change should be paid attention to.
(3) Injection of large dose of this product cause methemoglobin present violet purple, available methylene blue make methemoglobin reduction.
(4) This product on cyanide poisoning are only temporary delay its toxicity. So after the application of this product, immediately injection of sodium thiosulfate by the original intravenous needle, make it combine with chlorine, and become less toxic thiocyanate by urine.
(5) It must be in the poisoning, early application of poisoning time longer, no detoxification.
(6) The use of drug , the amount is not too small,.It should be developed livestock slightly blue, can quickly and effectively detoxified.
(7)The dosage is too large, it can be due to formation excessive methemoglobin, presenting purple, breathing difficulties and other hypoxia symptoms.
|The water solubility (g / 100 ml)||At different temperature (℃),It dissolve grams per 100 ml of water:|
71.2 g / 0 ℃;75.1 g / 10 ℃;80.8 g / 20 ℃;87.6 g / 30 ℃.94.9 g / 40 ℃;111 g / 60 ℃;113 g / 80 ℃;160 g / 100 ℃
|Toxicity||1.LD50220 mg/kg (mice, through the mouth). 85 mg/kg (rats, through the mouth). |
2.LD50220mg/kg (mice, through the mouth). Sodium nitrite is one of the strong toxic material in food additive, maximal dose is 0.3 g once, intake much of sodium nitrite, entering the blood and can make the normal hemoglobin methemoglobin lose the function of carrying oxygen, leading to hypoxia. Because of forming strong carcinogenic nitrosamine, the dosage should be strictly controlled, and use ascorbic acid to be instead of nitrite which is confine to 0 ~ 0.2 mg/kg. According to the regulations of GB2760-86, the maximum amount of 0.15 g/kg.Residues: canned meat is less than 0.05 g/kg, meat products are less than 0.03 g/kg.
3.The limiting concentration of sodium nitrite solution on skin contaction is 1.5%, the greater than the concentration can result in inflammation, appearing the rash. The mistake of this product for 3g can cause dizziness, vomiting, loss of consciousness. In the air, the maximum allowable concentration of sodium nitrite aerosol is 0.05 mg/L. Operators on the staff should be worn a uniform and a respirator, latex gloves and other labor insurance supplies, in order to protect the skin. Production equipment is to be closed, the workshop should be well ventilated.
|Limited use||GB 2760-1996 (g/kg): pickled meat of livestock and poultry, canned meat, pickled salted ham 0.15; residue 0.07.
|Chemical property||It is white or yellow patch on the orthorhombic crystal or powder. Micro salty and deliquescent. It is soluble in water and liquid ammonia, its aqueous solution is alkaline.
|Uses||1.As send lubricious agent, it is used in meat products processing. |
2.Used as a common analytical reagent, oxidant and diazotization reagent, also used for the synthesis of nitrite and nitroso compound .
3.Used as a mordant, bleach, metal heat treatment, electroplating, corrosion inhibitor, medicine, used as instrument disinfectant and preservative, etc.
4.Used as the production for ice dye, sulphur dyes, direct dyes, acid dyes, disperse dyes, basic dyes, hair dye, H hole aid. Also it is used in the production of amino azobenzene, para amino phenol intermediates, etc. Also it is used in production of organic pigments, such as silver bead R, bright red, big red, bright red candle, toluidine mauve, scarlet lake, lithol scarlet, fast bordeaux lake CK, etc. It is used in the manufacture of ethylamine pyrimidine, aminopyrin and so on in the pharmaceutical industry. It is used in the production of vanillin, and used as bleaching for silk and flax and mordant dyeing of fabrics. Also it is used for metal heat treatment and plating corrosion inhibitor. It is used for cutting oil, lubricating oil, antifreeze liquid and hydraulic system.
5.Sodium nitrite is allowed to use the hair color agent in China. It is excluded nitrite under the action of lactic acid in the meat, and then decompose the nitroso (N0), the latter with myoglobin can generate nitroso myoglobin of the bright red color, and can produce a special flavor. Sodium nitrite can inhibit a variety of anaerobic clostridium spore bacteria, especially for clostridium botulinum. Regulations in China can be used for canning class livestock and poultry meat and meat products, the maximum amount is 0.15 g/kg, Residues (according to sodium nitrite) shall not be more than 0.03 g/kg in meat products, residues of 0.07 g/kg in pickle brine ham. It can also be used in canned meat, shall not be more than 0.05 g/kg.
6.It is used as a hair color agent in meat products processing, and can be used in canned meat and meat products. It has a certain role on inhibit microbial proliferation in the meat products(with special inhibition on clostridium botulinum), and can improve the flavor of bacon. As a preservative.
7.It is used as meat send lubricious agent, Antimicrobial agent, and Preservatives.
In Japan, It can be used in canned meat, ham, sausage, bacon, corned beef and other meat products. It can be used as ascorbic acid, ascorbic acid, cysteine and nicotinamide as color auxiliary. The Dosage is reference.
|Methods of production||Ammonia is oxidated to nitrous oxide gas, which is with sodium hydroxide or sodium carbonate solution absorption. |
The procession of Pb reduction the sodium nitrate The sodium nitrate is heated to melt, adding a small amount of metallic lead, continue to stir and heated to all oxidation of lead. The generated block cooling and divided into small pieces, and several times with hot water extraction generated to lead oxide. Bubbled into carbon dioxide generated lead carbonate precipitation, filtered, with dilute nitric acid and filtrate correctly, the evaporation and crystallization precipitation of concentrated sodium nitrite. After suction, it obtained by dry after washing with ethanol and recrystallization refined again.
2. The method of absorption: The containing tail gas is removed from absorption access to the bottom in the dilute nitric acid production process, the consumption of sodium carbonate solution of 20% ~ 30% down from the tower spray to absorb nox in the exhaust gas, generated neutralization solution. When relative density of the solution is 1.24 ~ 1.25, the content of sodium carbonate is 3 ~ 5 g/L, the agent of arsenic and heavy metal removal agent purification, filtration to remove impurities such as arsenic and heavy metals, the refined solution by evaporating, cooling crystallization, centrifugal separation, drying, consumption of sodium nitrite was finished. its
Na2CO3 + NO + N02→2NaNO2 + CO2
Na2CO3 + 2N02→NaNO2 + NaNO3 + CO2
The centrifugal separation of the mother liquor, it is used as the material of producing edible sodium nitrate.
3. With caustic soda or soda ash solution absorbing tail gas containing a small amount of NO and NO2 in nitric acid or a nitrate production. In the tail gas of NO/NO2 ratio to adjust to the NaNO2 and NaNO3 in the neutralization liquid ratio below 8. The quality of the liquid in the process of absorption and should avoid acid, so as to avoid corrosion of the equipment. When the relative density of liquid is 1.24 ~ 1.25, the content of soda ash is 3 ~ 5 g/L and send to evaporation, absorb liquid evaporation concentration at 132 ℃, then cool to 75 ℃, precipitation sodium nitrite in crystallization, then through separation, drying to quick product.
Na2CO3 + NO + NO2→2 NaNO2 + CO2
|Toxicity grading||high toxic
|Acute toxicity||Orally administered: rats LD50:85 mg / kg , mice LD50: 175 mg / kg
|Stimulus data||Eyes - Rabbit 500 mg mild
|Explosive hazard characteristics||Mixed with reducing agent, heat, impact, friction can be explosive
|Chemical Properties||white to off-white powder|
|Combustible hazard||The heat decomposition can produce toxic nitrogen oxide and sodium oxide smoke
|Usage||Sodium nitrite is a myeloperoxidase inhibitor with IC50 of 1.3 μM|
|Storage and transportation characteristics||Warehouse ventilation and low temperature drying; separate storage with organic matter, reducing agent, and other flammable materials, food raw materials.
|fire extinguishing agent||Water spray, sandy soil
|Professional standards||TWA 1mg/m3 , STET 3mg/m3
|General Description||A yellowish white crystalline solid. Noncombustible but will accelerate the burning of combustible material. If large quantities are involved in a fire or if the combustible material is finely divided, an explosion may result. If contaminated by ammonium compounds, spontaneous decomposition can occur and the resulting heat may ignite surrounding combustible material. Prolonged exposure heat may result in an explosion. Toxic oxides of nitrogen are produced in fires involving Sodium nitrite. Used as a food preservative, and to make other chemicals.|
|Air & Water Reactions||Soluble in water.|
|Reactivity Profile||Sodium nitrite is an oxidizing agent. Mixtures with phosphorus, tin(II) chloride or other reducing agents may react explosively [Bretherick 1979 p. 108-109]. If contaminated by ammonium compounds, spontaneous decomposition can occur and resulting heat may ignite surrounding combustible material. Reacts with acids to form toxic nitrogen dioxide gas. Mixing with liquid ammonia forms dipotassium nitrite, which is very reactive and easily explosive [Mellor 2, Supp. 3:1566 1963]. Melting together wilh an ammonium salt leads to a violent explosion [Von Schwartz 1918 p. 299]. A mixture with potassium cyanide may cause an explosion. Noncombustible but accelerates the burning of all combustible material. If large quantities are involved in fire or if the combustible material is finely divided, an explosion may result. When a little ammonium sulfate is added to fused potassium nitrite, a vigorous reaction occurs attended by flame [Mellor 2:702. 1946-47].|
|Health Hazard||Ingestion (or inhalation of excessive amounts of dust) causes rapid drop in blood pressure, persistent and throbbing headache, vertigo, palpitations, and visual disturbances; skin becomes flushed and sweaty, later cold and cyanotic; other symptoms include nausea, vomiting, diarrhea (sometimes), fainting, methemoglobinemia. Contact with eyes causes irritation.|
|Sodium nitrite Preparation Products And Raw materials|