20 17,10127 October, the list of carcinogens published by the International Agency for Research on Cancer of the World Health Organization was preliminarily sorted out for reference. Trichloroethylene is in the list of carcinogens.
Chinese name: trichloroethylene mbth: trichloroethylene alias: trichloroethylene molecular formula: C2HCl3 Relative molecular weight: 13 1.39 Chemical category: organic controlled type: uncontrolled storage mode: sealed storage CASNo. : 79-065438+ 0-6 Physical and chemical properties, physical properties, chemical properties, functions and uses, properties and stability, precautions for use, risk overview, first-aid measures, fire-fighting measures, emergency treatment of leakage, operation and disposal and storage, toxicological data, environmental impact, health hazards, environmental behaviors, preparations, market prospects and physical and chemical properties. Physical properties and characteristics of trichloroethylene: colorless and transparent liquid, with an odor similar to chloroform. Melting point (℃):-87. 1 relative density (water = 1): 1.46 boiling point (℃): 87. 1 relative vapor density (air = 1): 4.53 molecular formula:. Combustion heat (kj/mol): 96 1.4 critical temperature (℃): 27 1 critical pressure (MPa): 5.02 octanol/water partition coefficient logarithmic value: 2.4 upper explosion limit% (v/v): 90.0 ignition temperature (℃): 420 lower explosion limit. React with 90% sulfuric acid to generate monochloroacetic acid; Pentachloroethane is formed by adding chlorine. When heated or at high temperature, it reacts with oxygen to produce highly toxic phosgene. Solvent with excellent performance and use, used as metal surface treatment agent, cleaning agent before electroplating and painting, metal degreasing agent and extractant for fat, oil and paraffin. Used in organic synthesis and pesticide production. Trichloroethylene is used to produce tetrachloroethylene, which can be used as an insect repellent; It is used to produce hexachloroethane, as an animal repellent, and to prevent and treat liver and stomach bdellosis, clonorchiasis and nematodiasis of ruminants. Performance and stability 1. Chemical properties: trichloroethylene without stabilizer is gradually oxidized in air to produce phosgene, carbon monoxide and hydrogen chloride. A small amount of dimer (hexachlorobutene) may also be produced. The reaction was carried out according to the free radical process, and illumination and heating obviously promoted the reaction. In the presence of water, dichloroacetyl chloride is decomposed into dichloroacetic acid and hydrogen chloride. Acidic substances produced by decomposition corrode metals. Therefore, trichloroethylene commonly used in industry needs to add a small amount of stabilizers such as phenols (hydroquinone), amines or alcohols. In the presence of air, moisture and light, trichloroethylene with stabilizer will not react with general industrial metal materials even if it is heated to 130℃. 2. Trichloroethylene vapor is heated to above 700℃ and decomposed to form a mixture of dichloroethylene, tetrachloroethylene, carbon tetrachloride, chloroform and methyl chloride. When trichloroethylene vapor is strongly exposed to air, it is completely oxidized to produce carbon dioxide, hydrogen chloride, carbon monoxide and phosgene. In the presence of copper salt, trichloroethylene is heated to 65438 075℃ under pressure and reacts with aqueous solution or suspension of alkali metal or alkaline earth metal hydroxide to generate glycolate. Trichloronitromethane and monochlorodinitromethane can be obtained by controlling the reaction conditions. Under the catalysis of aluminum trichloride, it reacts with hydrogen chloride at 30~50℃ to produce 1, 1, 1, 2- tetrachloroethane. In the presence of caustic alkali, dehydrochlorination is easy to generate dichloroacetylene, which spontaneously ignites in the air and explodes and decomposes. Sodium carbonate and liquid ammonia do not react with trichloroethylene under normal circumstances. Metal aluminum, especially powdered metal aluminum, can promote the decomposition of trichloroethylene to produce hydrogen chloride without stabilizer, and at the same time, it will undergo strong explosive decomposition or carbonization. The reaction produces aluminum trichloride, which is used as Foucault catalyst to promote the condensation reaction of trichloroethylene to produce pentachlorobutadiene, and pentachlorobutadiene is further condensed into resin and tar. In the presence of aluminum trichloride, trichloroethylene reacts with chloroform to form 1, 1, 1, 2,3,3-hexachloropropane. React with carbon tetrachloride to form 1, 1, 1, 2,3,3-heptachloropropane. In the presence of peroxide such as benzoyl peroxide, heating under pressure to 150~200℃ to obtain dimers and trimers of trichloroethylene. Catalyzed by ferric chloride, pentachloroethane and hexachloroethane are easily chlorinated. 3. Stability: Stability 4. Prohibited compounds: strong oxidizing agent, strong reducing agent, strong alkali, aluminum and magnesium 5. Conditions to avoid contact: light and ultraviolet 6. Risk of polymerization 7. Decomposition products: Precautions for the use of hydrogen chloride Overview of health hazards: This product mainly has anesthetic effect on the central nervous system. It can also cause damage to liver, kidney, heart and trigeminal nerve. Acute poisoning: A large amount of exposure to this product (inhalation, transdermal or oral) in a short time can cause acute poisoning. Inhalation of extremely high concentrations can lead to rapid coma. Inhalation of high concentrations may cause eye and upper respiratory symptoms. Headache, dizziness, drunkenness, drowsiness, etc. occur after several hours of contact. In severe cases, delirium, convulsions, coma, respiratory paralysis and circulatory failure will occur. Cranial nerve damage can occur, mainly trigeminal nerve damage, and cardiac damage is mainly arrhythmia. There may be liver and kidney damage. Oral and digestive tract symptoms are obvious, and liver and kidney damage is prominent. Chronic poisoning: still controversial. Headache, dizziness, fatigue, sleep disorder, gastrointestinal dysfunction, peripheral neuritis, myocardial injury, trigeminal paralysis and liver injury. Can cause skin damage. Environmental hazard: it is serious to the environment and can pollute water and atmosphere. Explosion hazard: this product is flammable, toxic and * * *. First-aid measures for skin contact: Take off the contaminated clothes immediately and rinse the skin thoroughly with soapy water and clean water. See a doctor. Eye contact: Lift eyelids and rinse with running water or normal saline. 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. If breathing stops, give artificial respiration immediately. See a doctor. Intake: Drink enough warm water to induce vomiting. See a doctor. Hazard characteristics of fire control measures: fire and high heat can cause combustion and explosion. Contact with strong oxidants will lead to chemical reactions. It decomposes when it is irradiated by ultraviolet rays or burned or heated, resulting in toxic phosgene and corrosive hydrochloric acid smoke. Harmful combustion products: carbon monoxide, carbon dioxide, hydrogen chloride and phosgene. Fire extinguishing method: Firefighters must wear oxygen breathing apparatus. Spray water to keep the burning container cool until the fire goes out. Extinguishing agent: atomized water, foam, dry powder, carbon dioxide, sand. Emergency treatment of leakage: evacuate the personnel in the leakage and pollution area to a safe area quickly, isolate them, 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. Prevent it from flowing into confined spaces such as sewers and flood discharge ditches. Small amount of leakage: adsorbed or absorbed by sand or other nonflammable substances. A large number of leaks: damming or digging holes to contain them. Cover with foam to reduce steam disaster. Pump it into a tank car or a special collector with a pump, and recycle it or transport it to a waste disposal site for treatment. Precautions for operation, disposal and storage: close the operation and strengthen ventilation. Operators must be specially trained and strictly abide by the operating procedures. It is recommended that the operator wear self-priming filter gas mask (half mask), chemical safety glasses, gas permeation prevention work clothes and chemical gloves. Stay away from fire and heat sources, and smoking is strictly prohibited in the workplace. Use explosion-proof ventilation system and equipment. Prevent the steam in the workplace from leaking into the air. Avoid contact with oxidants, reductants, alkalis and metal powders. When handling, handle with care to prevent the packaging and containers 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. The storage temperature shall not exceed 25℃ and the relative humidity shall not exceed 75%. The package should be sealed and not in contact with air. Should be stored separately from oxidant, reducing agent, alkali, metal powder and edible chemicals, and should not be mixed. Should not be stored in large quantities or for a long time. Equipped with corresponding varieties and quantities of fire fighting equipment. The storage area should be equipped with emergency response equipment for leakage and suitable accommodation materials. Toxicity of toxicological data: cumulative. Acute toxicity: LD 502,402 mg/kg (by mouth in mice); LC5045292mg/m3 for 4 hours (inhaled by mice); 137752mg/m3, 1 hour (inhaled by rats); Inhalation of 6.89g/m3×6 minutes, mucosa * * *; Inhalation of 5.38 g/m3× 1.20 minutes leads to decreased vision; People inhale 400ppm and smell it, which is slightly eye-catching; People inhale 2000ppm, a very strong smell, which is unbearable. Subacute and chronic toxicity: Rats inhaled 0.54g/m3 for 5 hours/day, 5 days/week and 3 months, and the nerve conduction velocity slowed down. Mutagenicity: DNA inhibition: 5mg/L of human lymphocytes. Sister chromatid exchange: human lymphocyte1.78 mg/L. Reproductive toxicity: the lowest toxic concentration inhaled by rats (TCL 0): 1.800 ppm(24 hours) (pregnancy 1 ~ 20 days), which causes abnormal musculoskeletal development. The lowest inhalation toxicity concentration (TCL 0) of mice:100 ppm/7 hours (5 days, male), * * * abnormal. Carcinogenicity: IARC Carcinogenicity Comments: Animals are positive, but humans don't know. Impact on the environment This substance has serious harm to the environment, and special attention should be paid to the pollution of air, water environment and water sources. Bioaccumulation occurs in the food chain that is important to human beings, especially aquatic organisms. Invasive routes of health hazards: inhalation, ingestion and percutaneous absorption. Health hazard: This product mainly has anesthetic effect on the central nervous system. It can also cause damage to liver, kidney, heart and trigeminal nerve. Hazard characteristics of environmental behavior: combustion and explosion caused by open flame and high heat energy. Contact with strong oxidants will lead to chemical reactions. It decomposes when it is irradiated by ultraviolet rays or burned or heated, resulting in toxic phosgene and corrosive hydrochloric acid smoke. Combustion (decomposition) products: carbon monoxide, carbon dioxide, hydrogen chloride, phosgene. Compilation of 1 Acetylene method This method uses acetylene and chlorine produced by calcium carbide as raw materials, carbon tetrachloride as diluent and ferric chloride as catalyst to synthesize 1, 1, 2,2-tetrachloroethane in liquid phase, and then adds lime milk for dehydrochlorination to obtain crude trichloroethylene, and then obtains the product through crude distillation and rectification. Because of the high price of acetylene, most of them use ethylene method. 2. The mixture of tetrachloroethane and pentachloroethane was obtained by direct chlorination of ethylene, and trichloroethylene and tetrachloroethylene were obtained by gas phase cracking. 3. Ethylene oxychlorination method This method uses ethylene, oxygen (or air) and chlorine as raw materials, and after catalytic chlorination and oxidation, trichloroethylene products and tetrachloroethylene are obtained. Market prospect from 200/kloc-0 to 2003, the market price of trichloroethylene products in China has not changed much, and it is relatively stable, and the domestic price is basically stable between 5000 and 6500 yuan /t, but the price of products imported from ICI company in Britain is higher, generally more than 2000 yuan /t higher than that of other importing countries and domestic products, followed by Dow chemical products in the United States, and the price is also nearly 2000 yuan /t higher. The price of trichloroethylene has been rising since 2005. In 2009, due to the shutdown of some foreign production facilities, the supply was once tight and the price rose. The domestic price of trichloroethylene rose to 7500 ~ 7800 yuan /t, and rose to more than 10000 yuan /t in 20 10165438 years later. The main reasons are: (1) the upstream raw materials of calcium carbide and liquid chlorine are weak and the cost support is insufficient; (2) The downstream refrigerant R 134a market also shows a weakening trend, and the demand decreases. At the same time, the demand of downstream cleaning industry has also declined, and manufacturers have sufficient inventory; (3) Traders have a strong wait-and-see mood, and manufacturers have obvious shipping intentions, and they have lowered their quotations. By the end of 20 12, the domestic market of trichloroethylene has gradually stabilized. The average price quoted by manufacturers is 6350 ~ 6500 yuan /t, the delivery price of downstream manufacturers is 6 150 ~ 6300 yuan /t, the price quoted in East China market is 6400 ~ 6500 yuan /t, and the price quoted in Northeast China market is 6500 yuan/t. Trichloroethylene is an organochlorine product with excellent performance and wide application, and its market prospect is bound to be good. However, judging from the price trend of trichloroethylene in recent years, its own market is easily affected by foreign imports and domestic supply and demand. It is suggested that vicious competition should be avoided for the healthy development of trichloroethylene industry in China. Instead of blindly building new trichloroethylene projects, we should control the total amount and maintain the overall balance between supply and demand. The existing equipment should focus on improving the production technology level, reducing the production cost and improving the product quality; At the same time, actively expand the application field of trichloroethylene, develop high-end products and increase added value; It is also necessary to build a smooth and orderly information exchange platform to promote the benign development of the market. Enterprises should maintain a transparent information exchange mechanism to avoid low-price competition and vicious competition.