Benzoic acid is a scaly or needle-like crystal with the smell of benzene or formaldehyde. The melting point is 122.13℃, the boiling point is 249℃, and the relative density is 1.2659 (15/4℃). It sublimates rapidly at 100°C, and its vapor is highly irritating and can easily cause coughing after inhalation. Slightly soluble in water, easily soluble in organic solvents such as ethanol and ether. Benzoic acid is a weak acid, stronger than fatty acids. They have similar chemical properties and can form salts, esters, acid halides, amides, acid anhydrides, etc., and are not easily oxidized. Electrophilic substitution reaction can occur on the benzene ring of benzoic acid, mainly obtaining meta-substitution products.
Basic information
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Chinese name
benzoic acid
Foreign name
Benzoic Acid
Melting point
122.13℃
boiling point
249℃
Chemical equation
C6H5COOH
Relative density
Molecular weight
122.1214
Drug classification
Disinfection and antiseptic
Simple structure
C6H5-COOH (benzene ring-COOH)
Purpose
[Use 1] Used in the production of medicines, dye carriers, plasticizers, spices and food preservatives, etc., and also used to improve the performance of alkyd resin coatings.
[Use 2] Mainly used for antifungal, disinfection and antisepsis.
[Use 3] Used as chemical reagents and preservatives.
【Use 4】Usually used as a fixative or preservative. Also used as a flavor preserving agent for fruit juice drinks. Can be used as an incense stick or as an incense stick. It can also be used in food flavors such as chocolate, lemon, orange, berries, nuts, candied fruits, etc. It is also commonly used in tobacco flavors.
[Use 5] Preservative; antimicrobial agent.
Due to the low solubility of benzoic acid, it must be fully stirred before use, or it must be dissolved in a small amount of hot water or ethanol. When used in concentrated fruit juices for refreshing drinks, benzoic acid is easily volatilized with water vapor, so its sodium salt is commonly used. 1g sodium salt is equivalent to 0.847g benzoic acid.
[Use 6] Benzoic acid is an important acid-type food preservative. Under acidic conditions, it has an inhibitory effect on mold, yeast and bacteria, but has a weak effect on acid-producing bacteria. The optimal pH value for bacteriostasis is 2.5 to 4.0, and generally a pH value lower than 4.5 to 5.0 is appropriate. In the food industry, the maximum usage amount of concentrated fruit and vegetable juices in plastic barrels shall not exceed 2.0g/kg; in jams (excluding cans), juice (flavored) beverages, soy sauce, and vinegar, the maximum usage amount is 1.0g/kg; The maximum usage amount in soft candies, wine, and fruit wine is 0.8g/kg; in low-salt pickles, sauces, and preserves, the maximum usage amount is 0.5g/kg; and the maximum usage amount in carbonated drinks is 0.2g/kg. Since benzoic acid is slightly soluble in water, a small amount of ethanol can be used to dissolve it during use.
[Use 7] Benzoic acid is an important acid-type feed preservative. Under acidic conditions, the optimal pH for bacteriostasis is 2.5-4.0, generally lower than pH 4.5-5.0.
Emergency measures
Accidental leakage treatment
Isolate the leaked contaminated area, set up warning signs around it, and cut off the source of fire. Emergency responders should wear gas masks and general fire protective clothing. Use a clean shovel to collect it in a dry, clean and covered container and transport it to a waste disposal site. If there is a large amount of leakage, collect and recycle or dispose of it after harmless treatment.
Protective measures
Respiratory system protection: When the concentration in the air exceeds the standard, wear a mask-type respirator. During emergency rescue or evacuation, it is recommended to wear self-contained breathing apparatus.
Eye protection: Wear chemical safety glasses.
Protective clothing: Wear acid and alkali resistant overalls.
Hand protection: Wear chemical-resistant gloves.
Others: After work, shower and change clothes. Pay attention to personal hygiene. Get regular physical exams.
First aid measures
Skin contact: Take off contaminated clothing and rinse thoroughly with plenty of running water.
Eye contact: Open the upper and lower eyelids immediately and rinse with running water or saline. Seek medical attention.
Inhalation: Leave the scene quickly to fresh air. Keep your airway open. Give nitrogen infusion when breathing is difficult. Once breathing stops, begin CPR immediately. Seek medical attention.
Ingestion: If swallowed by mistake, rinse mouth, drink milk or egg white, and seek medical attention.
Fire-fighting methods: mist water, foam, carbon dioxide, dry powder, sand.
Notes
External use of this product may cause mild local irritation. Ointments should not be stored in places where the temperature is too high.
Environmental hazards: It is harmful to the environment and can cause pollution to water bodies and the atmosphere.
Explosion hazard: This product is flammable and irritating.
Hazardous characteristics: Combustible when exposed to open flames and high heat.
Toxicological information
It is highly toxic to microorganisms, but its sodium salt has very low toxicity. Oral LD50 for rats: 1700mg/kg. It is not harmful to the body if taken orally below 0.5g per day, and there is no harm to health even if the dosage does not exceed 4g. In human and animal tissues, it can be combined with glycine of protein components to detoxify and form hippuric acid
Absorption
After oral ingestion of benzoic acid and sodium benzoate, 100% absorption from the gastrointestinal tract of experimental animals or humans can be assumed. In humans, peak plasma concentrations are reached in 1 – 2 hours.
Toxicity manifestations
Skin Hazards: Redness, burning sensation, itching.
Aspiration hazards: cough, sore throat.
Eye hazards: redness, pain.
Hazard if swallowed: abdominal pain, nausea, vomiting.
Health Hazards
Routes of invasion: inhalation, ingestion.
Health hazards: Mildly irritating to skin. Vapors are irritating to upper respiratory tract, eyes and skin. There is no obvious hazard in contact with this product under normal circumstances.
Acute toxicity
502530mg/kg (orally for rats); 2370mg/kg (orally for mice); 500mg/kg (orally for humans); the minimum toxic dose for humans is 6mg/kg, which may cause skin damage.
Hazardous characteristics: There is a danger of burning when exposed to high heat, open flame or contact with oxidants.
��Administer nitrogen when breathing is difficult. Once breathing stops, begin CPR immediately. Seek medical attention.
Ingestion: If swallowed by mistake, rinse mouth, drink milk or egg white, and seek medical attention.
Fire-fighting methods: mist water, foam, carbon dioxide, dry powder, sand.
Notes
External use of this product may cause mild local irritation. Ointments should not be stored in places where the temperature is too high.
Environmental hazards: It is harmful to the environment and can cause pollution to water bodies and the atmosphere.
Explosion hazard: This product is flammable and irritating.
Hazardous characteristics: Combustible when exposed to open flames and high heat.
Toxicological information
It is highly toxic to microorganisms, but its sodium salt has very low toxicity. Oral LD50 for rats: 1700mg/kg. It is not harmful to the body if taken orally below 0.5g per day, and there is no harm to health even if the dosage does not exceed 4g. In human and animal tissues, it can be combined with glycine of protein components to detoxify and form hippuric acid
Absorption
After oral ingestion of benzoic acid and sodium benzoate, 100% absorption from the gastrointestinal tract of experimental animals or humans can be assumed. In humans, peak plasma concentrations are reached in 1 – 2 hours.
Toxicity manifestations
Skin Hazards: Redness, burning sensation, itching.
Aspiration hazards: cough, sore throat.
Eye hazards: redness, pain.
Hazard if swallowed: abdominal pain, nausea, vomiting.
Health Hazards
Routes of invasion: inhalation, ingestion.
Health hazards: Mildly irritating to skin. Vapors are irritating to upper respiratory tract, eyes and skin. There is no obvious hazard in contact with this product under normal circumstances.
Acute toxicity
502530mg/kg (orally for rats); 2370mg/kg (orally for mice); 500mg/kg (orally for humans); the minimum toxic dose for humans is 6mg/kg, which may cause skin damage.
Hazardous characteristics: There is a danger of burning when exposed to high heat, open flame or contact with oxidants.
