First, emergency response to leakage

Quickly evacuate personnel from the leaked contaminated area to a safe area, isolate them, and strictly restrict access. Cut off the source of fire. It is recommended that emergency handlers wear self-contained positive-pressure respirators and fire protective clothing. Cut off the source of the leak as much as possible to prevent entry into the sewer, drainage Restricted spaces such as flood ditch. Small leakage: absorbed with activated carbon or other inert materials. It can also be scrubbed with an emulsion made of non-combustible dispersant, and the washing liquid is diluted and put into the waste water system. A large amount of leakage: build a dyke or dig a pit Contain; Cover with foam to suppress evaporation. Use explosion-proof pumps to transfer to tankers or special collectors, recycle or transport to waste disposal sites for disposal. Quickly collect xylene-contaminated soil and transfer to safe areas. Contaminated areas Strengthen ventilation along the ground, evaporate residual liquid, and eliminate steam. Quickly build dams, cut off the flow of contaminated water, and use fences to limit the spread of xylene on the water surface. Suzhou xylene.

Second, protective measures

Respiratory protection: When the concentration in the air is high, wear a filter-type gas mask (half-mask). It is recommended to wear an air respirator for emergency rescue or evacuation. Isopropyl alcohol manufacturers

Eye protection: Wear chemical safety protective glasses.

Body protection: Wear protective work clothes.

Hand protection: Wear rubber gloves.

Others: No smoking, eating and drinking at the work site. After work, shower and change clothes. Pay attention to personal hygiene.

Third, first aid measures

Skin contact: Remove contaminated clothing and rinse skin thoroughly with soap and water.

Eye contact: Raise the eyelids and rinse with running water or saline. Seek medical attention.

Inhalation: Quickly leave the scene to fresh air. Keep the airway open. If breathing is difficult, give oxygen. If breathing stops, give artificial respiration immediately. Seek medical attention.

Ingestion: Drink plenty of water and induce vomiting. Seek medical attention.

Fire extinguishing method: Cool the container with water spray, if possible, move the container from the fire to an open area. Fire extinguishing agent: foam, carbon dioxide, dry powder, sand.

Purpose

It is widely used as a solvent in coatings, resins, dyes, inks and other industries; used as a synthetic monomer or solvent in pharmaceuticals, explosives, pesticides and other industries; it can also be used as a high-octane gasoline component, and is an important raw material for organic chemicals. It can also be used to remove asphalt from the car body. Hospital pathology department is mainly used for the transparency and dewaxing of tissues and sections.

Industrial o-xylene is used as a raw material, first washed with industrial concentrated sulfuric acid until the acid layer is colorless, and then sequentially washed with 10% sodium hydroxide solution and water until qualified, the aqueous layer is separated, dried over anhydrous calcium chloride, and then rectified, After the distillate is clear, the middle distillate is collected, which is pure. 

production method

1. According to the boiling point of each component of crude benzene, a fraction with a boiling range of 135 to 145 ° C is extracted by distillation to obtain xylene.

2. The platinum reforming method uses normal pressure distillation of light gasoline (the initial boiling point is about 138 ° C), cuts the fractions greater than 65 ° C, first removes the harmful impurities by catalytic hydrogenation through a molybdenum-containing catalyst, and then reforms through a platinum catalyst. Extraction with diethylene glycol ether solvent, and then rectification column by column, to obtain products such as benzene, toluene and xylene.

3. Toluene disproportionation method. In this method, a methyl group of one toluene is transferred to another 166 catalyst (aluminum-hydrogen-type mordenite) under the action of a catalyst, and reformed toluene (nitrated grade) and reformed recycled hydrogen (85% to 90%) are used as raw materials. Under the conditions of a reaction temperature of 400 ± 2 ° C. and a pressure of about 2 MPa, benzene and xylene were prepared by the reaction.

4. The petroleum light fraction is mixed with benzene through hydrorefining, catalytic reforming and separation to obtain xylene. Or the coked crude benzene is obtained by washing and fractional distillation.

Environmental hazard

Pollution source

Xylene is an important chemical raw material. Wastewater from organic synthesis, synthetic rubber, paints and dyes, synthetic fibers, petroleum processing, pharmaceuticals, cellulose and other production plants, as well as unsealed production equipment and workshop ventilation, are two environmentally-friendly products. The main source of toluene. Rollovers and leaks during transportation and storage, and fire may cause accidental pollution.