Most explosive accidents occur in laboratories with inflammable and explosive materials and pressure vessels.
1. Use equipment, pressure vessels (such as high pressure gas cylinders) in violation of the operating procedures to cause an explosion.
2. The equipment is aging, there are faults or defects, causing leakage of inflammable and explosive materials, causing explosions in case of sparks.
3. Improper handling of flammable and explosive materials, resulting in a burning explosion. Such items (such as trinitrotoluene, picric acid, ammonium nitrate, azide, etc.) are subjected to high temperature friction, impact, vibration and other external factors or contact with other substances that interfere with other properties, and a severe chemical reaction occurs. , a large amount of gas is generated to cause an explosion.
4. The strong oxidant is in conflict with the substance and the substance is easily decomposed, causing burning and explosion.
5. Explosion of equipment, medicines, etc. caused by fire accidents.
1. Peroxides, aromatic polynitro compounds and nitrates in organic compounds, dry diazonium salts, azides, heavy metal acetylides, etc., are all explosive materials, and should be paid special attention during use and operation. . When the peroxide-containing ether is distilled, there is a danger of explosion, and the peroxide must be removed beforehand. If there is a peroxide, it can be removed by adding an acidic solution of ferrous sulfate. Aromatic polynitro compounds are not suitable for drying in an oven. The combination of ethanol and concentrated nitric acid can cause a very strong explosion.
2. The instrument is incorrect or incorrectly operated and may cause an explosion. If distillation or heating is carried out under normal pressure, the instrument must be connected to the atmosphere. Be careful when distilling, do not evaporate the material. Glass instruments that are not resistant to external pressure (such as flat-bottomed flasks and Erlenmeyer flasks, etc.) cannot be used during decompression operations.
3. When a gas such as hydrogen, acetylene or ethylene oxide is mixed with air to a certain ratio, an explosive mixture will be formed, which will explode if exposed to an open flame. Therefore, an open flame must be strictly prohibited when using the above substances. For the synthesis reaction test with a large amount of heat release, carefully add the material slowly and pay attention to the cooling, and at the same time prevent accidents caused by the leakage of the piston of the dropping funnel.