Production method of sodium bisulfite and sodium metabisulfite

Skin contact: Take off contaminated clothing immediately and rinse with plenty of flowing water. See a doctor. 

Eye contact: Lift the eyelid immediately and rinse thoroughly with plenty of running water or saline for at least 15 minutes. See a doctor.

Inhalation: Quickly leave the scene to fresh air. Keep the airway clear. If breathing is difficult, give oxygen. If breathing stops, give artificial respiration immediately. See a doctor. Ingestion: Drink enough warm water to induce vomiting. See a doctor. 

The main symptoms of exposure to the chemical check the health effects: irritation to the skin, eyes, respiratory tract, can cause skin burns, damage to the cornea, can cause blindness, inhalation can cause allergic respiratory reactions, can cause asthma; long-term exposure, Causes chronic rhinitis, chronic bronchitis and tooth erosion.

Special note from the doctor: Treat according to the symptoms and show the label and SDS on the container when going to the doctor. 

Timely medical care and special treatment: treatment according to symptoms. Depending on the patient's condition and the specific circumstances of the accident, the treatment may be different. In all potential poisoning situations, on-site emergency treatment is crucial.

Fire-fighting measures

Fire-extinguishing method and extinguishing agent: This product is non-combustible. When causing fire with other substances, attention should be paid to the corrosivity of the substance. 1. Sodium bisulfite

Alias: sodium acid sulfite

English name: sodium hydrogensulfite

Molecular formula: NaHSO3

Relative molecular mass: 104.06

Appearance: white crystalline powder

Melting point: 150℃

Relative density: 1.48

Solubility: soluble in 3.5 parts cold water, 2 parts boiling water, about 70 parts ethanol, the aqueous solution is acidic

Quality Standard

Sodium bisulfite manufacturer

Application performance: Sodium bisulfite has strong reducing properties and has a destructive effect on vitamin B. It cannot be used in grains, meat and dairy products, but also in the preservation and processing of brewing, beverages, dried fruits, etc.

safety:

①Low toxicity, LD50 2000mg/kg (rat, oral)

② The skin, eyes and respiratory tract are irritating and can cause allergic reactions. May cause corneal damage and lead to blindness. Can cause asthma; large amounts of oral administration can cause nausea, abdominal pain, diarrhea, circulatory failure, central nervous system depression

③Hazardous to the environment and may cause pollution to water bodies

④ The product is non-flammable, corrosive and can cause burns

production method:

(1) Sodium bisulfite can be obtained by soda ash solution absorbing sulfuric acid tail gas or sulfur dioxide produced by sulfur combustion. The reaction formula is as follows: Na2CO3+2SO2+H2O→2NaHSO3+CO2

(2) Soda ash is slowly added to the sodium bisulfite mother liquor (containing NaHSO3 40%, pH value 3-4) to produce sodium sulfite solution (until the slurry pH reaches 7-8 as the end point); this sodium sulfite solution reacts in series It absorbs the SO2 gas (10%～13%) produced by sulfur combustion, the reaction generates sodium bisulfite (the reaction temperature no longer rises is the end point), a large amount of crystals are precipitated during the reaction, and the water content is separated by centrifugation 6%～10% of wet products, then dried and dehydrated by airflow at 250～300℃ to obtain products.

Sodium bisulfite manufacturers, sodium bisulfite manufacturers, sodium bisulfite manufacturers

2. Sodium metabisulfite

Alias: sodium sulfite

English name: sodium pyrosulfite

Molecular formula: Na2S2O5

Relative molecular mass: 190.09

Melting point: 300℃

Relative density: 1.40

Appearance: white or slightly yellow crystalline powder or small crystal

Quality standard: content ≥96.5% (calculated as Na2S2O5), iron (calculated as Fe) ≤0.003%; arsenic (calculated as As) ≤0.0001%; heavy metal (calculated as Pb) ≤0.0005%; clarity: pass the test.

Application performance: The metabisulfite is unstable, but the odor is relatively small, and the price is low. It is often used in the bleaching of fruits and vegetables

Dosage: 0.45g/kg for sugar, rock sugar, candy, honey money, glucose, liquid glucose, caramel, biscuits, bamboo shoots, vermicelli, mushrooms, and canned mushrooms. The residual amount is based on sulfur dioxide. Bamboo shoots, mushrooms and canned mushrooms should not exceed 0.05g/kg; biscuits, sugar, vermicelli and other varieties should not exceed 0.1g/kg; liquid glucose should not exceed 0.2g/kg; honey money should not exceed 0.05g/kg /kg.

Safety: ADI 0～0.75mg/kg (based on SO2, including total ADI value of sulfur dioxide and sulfite)

Production method: Sodium sulfite is absorbed with soda ash solution, and sodium metabisulfite is obtained through separation, drying and preparation