Hexane is a colorless liquid with low toxicity and a faint special odor. Hexane is a chemical solvent, mainly used in the polymerization of propylene and other olefins, the extractant of edible vegetable oil, the solvent of rubber and paint, and the diluent of pigment. It has certain toxicity and can enter the human body through the respiratory tract and skin. Long-term exposure can cause chronic poisoning symptoms such as headache, dizziness, fatigue, and numbness of the limbs. In severe cases, it can lead to fainting, loss of consciousness, cancer and even death.
Physical and chemical properties
【Melting Point (℃)】-95.3
【Boiling point (℃)】68
【Flash point (℃)】-25.5℃
【Ignition temperature (℃)】: 244
【Lower Explosion Limit% (V/V)】1.2%
[Upper limit of explosion% (V/V)] 7.4%
[Properties] A colorless volatile liquid with a faint special odor.
【Solubility】insoluble in water, miscible with ether and chloroform, soluble in acetone
Use
Hexane is mainly used as a solvent in industry, used to prepare viscose to bond shoe leather and luggage,
Commonly used in the wiping and cleaning operations in the production process of the electronic information industry, as well as the crude oil leaching in the food manufacturing industry, the recovery of propylene solvents in the plastic manufacturing industry, the extractant in chemical experiments (such as phosgene experiment) and daily chemistry Hexane is also used in industries such as floral solvent extraction during product production. If used improperly, it is very easy to cause occupational poisoning.
Health Hazards
Invasion route: inhalation, ingestion, transdermal absorption.
Health hazards: This product has anesthetic and stimulating effects. Long-term exposure can cause peripheral neuritis.
Acute poisoning: headache, dizziness, nausea, ataxia, etc. caused by inhalation of high concentration of this product, severe cases may cause loss of consciousness. Irritating to eyes and upper respiratory tract.
Chronic poisoning: headache, dizziness, fatigue, and decreased appetite after long-term exposure; afterwards, the distal extremities gradually develop paresthesia, numbness, touch, pain, vibration, and position loss, especially the lower limbs, and the upper limbs are less affected . It further develops into lower limb weakness, muscle pain, muscle atrophy and dyskinesia. Nerve-EMG examination showed that the conduction velocity of sensory nerve and motor nerve was slowed down.
Harmful effects and symptoms of short-term exposure to n-hexane: Inhalation or exposure to more than 500mg/kg can cause headaches. Acute diarrhea, face fever, numbness and weakness in fingers and toes. Exposure to more than 1300mg/kg can also cause nausea, rhinitis and pharyngitis. Exposure to more than 1500mg/kg can not only cause the above symptoms, but also cause blurred vision, loss of appetite and weight loss. If the exposure is stopped, most symptoms disappear within a few months. Inhalation of liquid n-hexane into the lungs can cause pneumonia.
Occupational chronic n-hexane poisoning is a systemic disease mainly caused by damage to the nervous system caused by long-term exposure to n-hexane gas in the production environment. In industrial supplies, n-hexane often contains a certain amount of organic matter such as benzene and toluene. Industries such as vegetable oil extraction, synthetic rubber, and polyethylene film printing can be exposed to n-hexane solvent. After entering the human body, it mainly affects the energy metabolism of the central nervous system, causing nerve fiber degeneration, leading to neurasthenia syndrome and autonomic dysfunction. The clinical manifestations are mainly the distal end of the extremities touch, pain, hypothermia, decreased muscle strength or paralysis of the limbs, etc. There is no uniform diagnostic standard in our country. Mild patients should get rid of n-hexane operation as soon as possible. Moderate patients can generally be cured, and severe patients can be left with lifelong disability.
Emergency treatment
Leakage emergency response
Quickly evacuate personnel from the contaminated area to a safe area, isolate them, and strictly restrict access. Cut off the fire source. Emergency handlers should wear protective equipment to enter the scene. Cut off the source of the leak immediately. Prevent entry into restricted spaces such as sewers and flood drains. Small leakage: Use sand or other non-combustible materials to absorb or absorb. It can also be scrubbed with an emulsion made of a non-flammable dispersant, and the lotion is diluted and put into the waste water system. A large number of leaks: construct dikes or dig pits for storage; cover with foam to reduce steam disasters. Use explosion-proof pumps to transfer to tank trucks or special collectors, recycle or transport to waste disposal sites for harmless treatment of esters to meet environmental protection requirements. .
Protection measures
Respiratory protection: When the concentration in the air exceeds the standard, wear a self-priming filter gas mask (half mask).
Eye protection: When necessary, wear chemical safety glasses.
Body protection: wear anti-static overalls. After the skin is contaminated, rinse it off with clean water immediately, and wash your hands before meals.
Hand protection: wear glass fiber gloves, benzene and oil resistant gloves.
Others: Wear a gas mask during operation, and smoking is strictly prohibited at the work site. Avoid long-term repeated contact.
In order to prevent n-hexane poisoning, effective ventilation devices should be installed in the n-hexane workshop. If a solvent containing n-hexane is used, it should be kept tightly closed as much as possible to reduce the escape of vapor, and it is advisable to ensure that the air concentration of n-hexane in the workshop does not exceed 100 mg/m3. Actively carry out process reforms, and replace n-hexane with non-toxic or slightly toxic solvents as much as possible.
First aid measures
Skin contact: Take off contaminated clothing and wash skin thoroughly with soap and water.
Eye contact: Lift the eyelid and rinse with running water or normal saline. Seek medical attention.
Inhalation: quickly leave the scene to a place with fresh air. Keep the airway unobstructed. If breathing difficulties occur, seek medical attention immediately and give oxygen. If breathing stops, give artificial respiration immediately. Seek medical attention.
Ingestion: Drink enough warm water, induce vomiting, and seek medical attention.
Fire fighting method: spray water to cool the container, and if possible, move the container from the fire scene to an open place. If the container in the fire scene has changed color or produces sound from the safety relief device, it must be evacuated immediately. Extinguishing agent: foam, dry powder, carbon dioxide, sandy soil. Extinguishing with water is ineffective.
Operation precautions
Airtight operation, full ventilation. Operators must undergo special training and strictly abide by the operating procedures. It is recommended that operators wear self-priming filter respirators (half-face masks), chemical safety glasses, anti-static overalls, and rubber oil-resistant gloves. Keep away from fire and heat sources, and smoking is strictly prohibited in the workplace. Use explosion-proof ventilation systems and equipment. Prevent the vapor from leaking into the air in the workplace. Avoid contact with oxidants. During filling, the flow rate should be controlled, and there should be a grounding device to prevent static electricity from accumulating. When handling, load and unload with care to prevent damage to packaging and containers. Equipped with corresponding types and quantities of fire-fighting equipment and leakage emergency treatment equipment. Empty containers may be harmful residues.
Storage considerations
Store in a cool, ventilated warehouse. Keep away from fire and heat sources. The storage temperature should not exceed 30°C. Keep the container tightly closed. should be kept away from oxidizer, do not store together. Use explosion-proof lighting and ventilation facilities. It is forbidden to use mechanical equipment and tools that are prone to sparks. The storage area should be equipped with leakage emergency treatment equipment and suitable storage materials.
Transportation considerations
Transport vehicles should be equipped with corresponding types and quantities of fire-fighting equipment and leakage emergency treatment equipment during transportation. It is best to transport sooner or later in summer. The tank (tank) truck used during transportation should have a grounding chain, and a hole partition can be set in the tank to reduce vibration and static electricity. Mixed shipment and transportation with oxidants and edible chemicals are strictly prohibited. Avoid exposure to the sun, rain, and high temperature during transportation. Stay away from fire, heat sources, and high-temperature areas during stopovers. The exhaust pipe of the vehicle carrying the item must be equipped with a fire arrester, and it is prohibited to use mechanical equipment and tools that are prone to sparks for loading and unloading. When transporting by road, follow the prescribed route and do not stop in residential or densely populated areas. It is forbidden to drop off during railway transportation. It is strictly forbidden to transport in bulk by wooden ships or cement ships.
