What is hydrocyanic acid? What is its essence?

Part I: Names of Chemicals

Chemical Chinese name: hydrogen cyanide

English name of chemical: hydrogen cyanide

Chinese name 2:

English name 2:

Technical specification code: 826

CAS number: 74-90-8

Molecular formula: HCN

Molecular structure: C atoms are bound by sp hybrid orbitals, with carbon-nitrogen triple bonds, and the molecules are polar.

Molecular weight: 27.03

Part II: Composition/Composition Information

Chemical abstracts service number of harmful biological components

Hydrogen cyanide 74-90-8

The third part: risk overview.

Hazard category:

Invasion route:

Health hazard: inhibition of respiratory enzymes, leading to intracellular asphyxia. Acute poisoning: Inhalation of high-concentration hydrogen cyanide gas in a short time can immediately stop breathing and die. Non-sudden death can be divided into four clinical stages: prodromal mucosal irritation, accelerated breathing, fatigue and headache; Oral administration has the tip of the tongue, oral numbness and so on. Dyspnea includes dyspnea, elevated blood pressure and bright red skin mucosa. Seizures, coma and respiratory failure occur during convulsions. During paralysis, the muscles of the whole body relax, breathing and heartbeat stop and die. Can cause eye and skin burns, and lead to poisoning through absorption. Chronic effects: neurasthenia syndrome, dermatitis.

Environmental hazards:

Explosion hazard: This product is flammable and highly toxic.

Part IV: First aid measures

Skin contact: Take off contaminated clothes immediately and rinse thoroughly with running water or 5% sodium thiosulfate solution for at least 20 minutes. See a doctor.

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

Inhalation: leave the scene quickly and go to a place with fresh air. Keep the respiratory tract unobstructed. If you have difficulty breathing, give oxygen. When breathing and heartbeat stop, artificial respiration (do not use mouth-to-mouth resuscitation) and chest compressions should be performed immediately. Inhale isoamyl nitrite and see a doctor.

Intake: Drink enough warm water to induce vomiting. Gastric lavage with 1:5000 potassium permanganate or 5% sodium thiosulfate solution. See a doctor.

Part V: Fire Prevention Measures

Hazard characteristics: flammable, its vapor and air can form an explosive mixture, which will cause combustion and explosion when exposed to open fire and high heat energy. If left for a long time, it will polymerize due to moisture, and the polymer itself has autocatalytic effect, which can cause explosion.

Harmful combustion products: nitrogen oxides.

Fire extinguishing method: cut off the gas source. If the gas source cannot be cut off, it is not allowed to extinguish the flame at the leak. Firefighters must wear full-body protective clothing and oxygen respirator, and work at a safe distance or with protective measures. Extinguishing agent: dry powder, anti-soluble foam, carbon dioxide. It is ineffective to put out the fire with water, but it is necessary to keep the burning container cool with water. Dispel steam with misty water.

Part VI: Emergency treatment of leakage.

Emergency treatment: evacuate the personnel in the leaked contaminated area to a safe area quickly, and immediately isolate 150m, and strictly restrict access. Cut off the fire. It is recommended that emergency personnel wear self-contained positive pressure breathing apparatus and protective clothing. Cut off the leakage source as much as possible. Reasonable ventilation and accelerated diffusion. Spray water is diluted and dissolved. Build a dike or dig a pit to contain a large amount of wastewater. If possible, it should be ignited to eliminate the accumulation of toxic gases. Or send the residual gas or leakage gas to the water washing tower or fume hood connected to the tower with exhaust fan. Leaked containers should be properly treated, repaired and inspected before use.

Part VII: Operation, Disposal and Storage

Precautions for operation: it should be tightly sealed to provide sufficient local exhaust and comprehensive ventilation. Operators must be specially trained and strictly abide by the operating procedures. Operators are advised to wear isolation respirator, integrated adhesive protective clothing and rubber gloves. Stay away from kindling and heat sources, and smoking is strictly prohibited in the workplace. Use explosion-proof ventilation system and equipment. Prevent gas or steam from leaking into the air in the workplace. Avoid contact with oxidants, acids and bases. Lightly load and unload when handling, so as to prevent the cylinders and accessories from being damaged. Equipped with corresponding varieties and quantities of fire fighting equipment and leakage emergency treatment equipment. Empty containers may leave harmful substances behind.

Precautions for storage: Store in a cool and ventilated warehouse. Stay away from fire and heat sources. Avoid light. The reservoir temperature should not exceed 30℃. The package should be sealed and not in contact with air. Should be stored separately from oxidants, acids, alkalis and edible chemicals, and should not be mixed. Adopt explosion-proof lighting and ventilation facilities. It is forbidden to use mechanical equipment and tools that are easy to generate sparks. The storage area should be equipped with emergency treatment equipment for leakage. The "five pairs" management system of highly toxic substances should be strictly implemented.

Part VIII: Contact Control/Personal Protection

occupational exposure limits

China MAC (mg/m3): 0.3 [pi]

Maximum allowable concentration in the former Soviet Union (mg/m3): 0.3

TLVTN: OSHA 10ppm， 1 1mg/m3； Acgih 10 ppm, 1 1 mg/m3 [epidermis] [upper limit]

TLVWN: No standard has been established.

Monitoring method: sodium isophthalate-barbiturate colorimetry.

Engineering control: tightly sealed, providing sufficient local exhaust and comprehensive ventilation. Adopt isolation operation. Mechanize and automate as much as possible. Provide safety shower and eye washing equipment.

Respiratory protection: When you may come into contact with toxic substances, you should wear an isolation respirator. Oxygen respirator must be worn during emergency rescue or evacuation.

Eye protection: respiratory protection has been done.

Physical protection: wear an integrated adhesive tape anti-virus suit.

Hand protection: wear rubber gloves.

Other protection: Smoking and eating are prohibited in the workplace. Maintain good hygiene habits. The workshop should be equipped with first aid equipment and medicines. Operators should learn to save themselves and help each other.

Part IX: Physical and Chemical Characteristics

Main ingredients: pure products

Colorless gas or liquid, with bitter almond flavor.

PH value:

Melting point (℃):- 13.2

Boiling point (℃): 25.7

Relative density (water = 1): 0.69

Relative steam density (air = 1): 0.93.

Saturated vapor pressure (kpa): 53.32 (9.8℃)

Combustion heat (kJ/mol): no data available.

Critical temperature (℃): 183.5

Critical pressure (MPa): 4.95