Components and toxicity of phosgene! !

This can be found anywhere on the internet... :L

The second floor is the correct answer. Why didn’t the original poster check the basic information by themselves? It’s worth posting about this too: (Baidu or Google will do; the first result on Baidu is: http://baike.baidu.com/view/62695.htm)

Phosgene is short for “light-formed gas”; it is a translation of Phosgene (where “Phos” means light, with the suffix -gene added). The U.S. military code name is CG. Overview
Name: Phosgene; Carbonyl chloride
English name: Phosgene; Carbonyl chloride
Molecular formula: COCl2
Molecular weight: 98.92
Structure: See figure
CAS No.: 75-44-5
National standard code: 23038
Derivatives (related substances):
Similar substances: Diphosgene, Triphosgene, Formaldehyde, Dichloromethane
Upstream products: Carbon tetrachloride, Fuming sulfuric acid, Carbon monoxide, Chlorine
Downstream products: Methyl chloroacetate, Isocyanates, Benzene sulfonoyl isocyanate, Methyl chloroformate, Ethyl chloroformate, 2-Ethylhexyl chloroformate, Diethyl carbonate, Dimethyl carbonate, Diphenyl carbonate, Chloroacetyl chloride, N,N’-Dimethyl-N,N’-diphenylurea, N-Chloromethyl-N-phenylcarbamoyl chloride, N,N’-Dissuccinimide carbonate, Tetraethylammonium chloride, Benzoyl chloride
Basic properties
Appearance: Colorless or slightly yellow gas (industrial-grade material is usually a light yellow liquid); when concentrated, it has a strong irritating or asphyxiating odor. 　　Melting point: -127.84°C (-118°C) Boiling point: 7.48°C (8.2°C) Specific heat capacity: Relative density: 3.5 (air = 1) ； 1.37 (water = 1) Vapor pressure: 202.65 kPa (27.3°C) Volatility: 6652.25 mg/L Stability: Stable Hazard symbols: 6 (toxic gas), 20 (corrosive) Solubility: Slightly soluble in water; it undergoes gradual hydrolysis. Soluble in most organic solvents such as aromatics, benzene, carbon tetrachloride, chloroform, and acetic acid Other: Highly toxic! Non-flammable. Production or source: In the laboratory, it can be produced by reacting carbon tetrachloride with hydrochloric acid. Heat carbon tetrachloride to 55–60°C and add fuming hydrochloric acid drop by drop; phosgene will then be released. If liquid phosgene is desired, the phosgene generated is condensed. 　　Phosgene is industrially produced by the reaction of carbon monoxide with chlorine. This is a highly exothermic reaction; the reactor equipped with activated carbon should have a water-cooled jacket to maintain the reaction temperature at around 200°C. To obtain high-quality phosgene and reduce equipment corrosion, an appropriate excess of thoroughly dried carbon monoxide should be maintained when mixed with chlorine. The mixture is fed from the upper part of the synthesizer; after passing through the activated carbon layer, it is quickly converted into phosgene. When a synthesizer with specifications of Ф700×2900 is used, each unit can produce 200 tons of phosgene per year. Raw material consumption quotas: chlorine (>99%) 925 kg/t, oxygen (under standard conditions) 268 (m3) kg/t, coke 400 kg/t. 　　Raw material consumption quota: Chlorine (>99%) 925 kg/t ； Oxygen (under standard conditions): 268 (m3)/kg/t ； Coke 400 kg/t. 　　Direct reaction of chloroform with hydrogen peroxide: CHCl3 + H2O2 = HCl + H2O + COCl2 (phosgene) – Chloroform can be oxidized to produce phosgene if not stored properly. 　　Oxygen can also be produced using hydrogen peroxide and then reacted with chloroform: 2CHCl3 + O2 = 2HCl + 2COCl2 (phosgene). In the event of a phosgene leak, it should be absorbed using water mist; phosgene readily undergoes hydrolysis: COCl2 + H2O = 2HCl + CO2. Uses Phosgene is an important organic intermediate in the production of pesticides ； Modern Medicine ； Engineering plastics ； Polyurethane materials have many uses, as does **. In pesticide production, it is used to synthesize the carbamate insecticide carbofuran ； Carbofuran ； Many varieties such as leafhopper powder are also used in the production of the fungicide carbendazim and various herbicides. China’s Linxiang Amino Chemicals Factory and Ningyang Pesticide Factory have become manufacturing bases for carbamate pesticides, with Ningyang Jiaoyao Factory capable of producing 43 different varieties. Isocyanate-based products produced from phosgene, such as TDI, MDI, and PAPI, are used in rigid polyurethane foams ； soft foam ； elastomer ； Important raw materials for synthetic leather ； Certain types of isocyanates are widely used in polyurethane coatings ； There are also special varieties used as adhesives, such as Lenca glue. It is used in the dye industry to produce dye intermediates such as alizarin acid, and in the defense industry to produce the fixing agent dimethyldiphenylurea as well as as a military poison gas. Chloroformates produced using phosgene are pesticides ； Pharmaceuticals ； Intermediates for organic synthesis such as polymerization initiators. When producing the engineering plastic polycarbonate by the direct phosgene method or the transesterification method, phosgene is required as a raw material. Phosgene is highly toxic and a strong irritant ； Asphyxiating gases. Inhalation of phosgene causes pulmonary edema ； Pneumonia and other conditions pose a risk of death. Toxicity Overview of poisoning This substance is a typical transient toxin. The median lethal dose LD50 for inhalation poisoning is 3200 mg·min/m3, and the median incapacitating dose is 1600 mg·min/m3. After inhalation, symptoms appear after a few hours of incubation, manifesting as difficulty breathing, chest pain, and decreased blood pressure; in severe cases, it can lead to coma and death. Gas masks provide effective protection and usually do not require disinfection. Antidotes include urotropine, among others. Artificial respiration is prohibited in those showing symptoms of pulmonary edema. 　　Detailed Information I. Health Hazards Routes of exposure: Inhalation, dermal absorption. 　　Health hazards: It primarily damages the respiratory tract, causing chemical bronchitis, pneumonia, and pulmonary edema. 　　Acute poisoning: In mild cases, patients experience symptoms such as tearing, photophobia, discomfort in the throat, coughing, and chest tightness. In moderate cases, in addition to an exacerbation of these symptoms, patients suffer from mild difficulty breathing and slight cyanosis. In severe cases, pulmonary edema or adult respiratory distress syndrome occurs; patients have severe coughing, produce large amounts of frothy sputum, experience respiratory distress, and show significant cyanosis. There is a period of symptom relief before the onset of pulmonary edema (usually 1–24 hours). Mediastinal and subcutaneous emphysema can occur concurrently. 　　II. Toxicological data and environmental behavior Acute toxicity: LC50 = 1400 mg/m3, 1/2 hour (inhalation by rats); inhalation of 3200 mg/m3 by humans is fatal; an inhalation concentration of 25 ppm for 30 minutes represents the minimum lethal concentration. 　　Subacute and chronic toxicity: When animals inhaled 0.0008 mg/L for 5 hours (5 days), 40% developed emphysema. 　　Sources of pollution: Phosgene is used as a treatment agent for polyurethane products, a plasticizer, a raw material for polycarbonates, a fiber treatment agent, an herbicide, a **stabilizer, dyes, dye intermediates, and raw materials for pharmaceuticals. Leaks, spills, or accidental releases during production can all lead to pollution. 　　Hazardous characteristics: Non-flammable. It has high chemical reactivity and is highly corrosive when in contact with water. 　　Combustion (decomposition) product: hydrogen chloride. 　　3. On-site emergency monitoring methods:
Rapid chemical analysis methods: Nitrobenzylpyridine detection tubes, diamine indicator paper method – from “Emergency Monitoring, Handling, and Disposal Techniques for Sudden Environmental Pollution Incidents”, edited by Man Bentai.
Gas detection tubes (products from Beijing Labor Protection Institute and German company Dräger).

4. Laboratory monitoring methods:
Ultraviolet spectrophotometry (HJ/T31-1999, for exhaust gases from fixed pollution sources).
Iodometric method – from “Methods for Monitoring and Analyzing Air and Exhaust Gases”, compiled by the Environmental Protection Bureau.

5. Environmental standards:
China (TJ36-79): Maximum allowable concentration of harmful substances in workshop air – 0.5 mg/m3.
China (GB16297-1996): Comprehensive emission standards for air pollutants.
① Maximum allowable emission concentrations (mg/m3):
5.0 (Table 1); 3.0 (Table 2).
② Maximum allowable emission rates (kg/h):
Level 2: 0.12–1.2 (Table 1); 0.10–1.0 (Table 2).
Level 3: 0.18–1.8 (Table 1); 0.15–1.5 (Table 2).
③ Monitoring limits for unorganized emissions (mg/m3):
0.080 (Table 2); 0.10 (Table 1).

6. Emergency handling and disposal methods:
I. Emergency response to leaks
Evacuate people from the area affected by the leak to areas upwind immediately, and isolate the area. For small leaks, an isolation zone of 150 meters should be established; for large leaks, 450 meters. Access to the area must be strictly restricted. It is recommended that emergency responders wear self-contained positive-pressure breathing apparatus and protective clothing. Enter the site from the upwind side. Seal the source of leakage as much as possible. Ensure proper ventilation to accelerate diffusion. Neutralize by spraying ammonia water or other dilute alkaline solutions. Construct dikes or dig pits to contain the large amount of wastewater generated. Leaking containers must be properly handled, repaired, and inspected before being reused. 　　Phosgene is highly hydrolyzable; even in cold water, its hydrolysis occurs at a rapid rate. Water sources, water-containing foods, and substances that absorb water easily will not become contaminated. Phosgene reacts rapidly with ammonia to produce mainly non-toxic substances such as urea and ammonium chloride; therefore, concentrated ammonia can be used to disinfect phosgene. Phosgene reacts with organic amines to produce a white precipitate of diphenylurea and aniline hydrochloride. This reaction can be used to test phosgene. Phosgene is rapidly decomposed in an alkaline solution to form non-toxic substances. Various bases and alkaline substances can be used to disinfect phosgene. 　　II. Protective Measures Respiratory protection: During normal operations, a filtered gas mask (full-face mask) should be worn. It is recommended to wear an air respirator during emergency rescue or evacuation. 　　Eye protection: Protection is provided under respiratory protection. 　　Body protection: Wear a rubberized gas mask suit. 　　Hand protection: Wear rubber gloves. 　　Others: Smoking, eating, and drinking are prohibited at the work site. Conduct pre-employment and regular health checks. 　　III. First aid measures Skin contact: Remove contaminated clothing and rinse with flowing water. 　　Eye contact: Lift the eyelids and rinse with flowing water or saline. Seek medical attention. 　　Inhalation: Quickly move to an area with fresh air. Keep the airway clear. If there is difficulty breathing, administer oxygen. If breathing stops, perform artificial respiration immediately. Seek medical attention. 　　Fire extinguishing method: This product is non-flammable. Firefighters must wear filter-type gas masks (full-face masks) or self-contained breathing apparatus, as well as full-body fire and gas-resistant suits, to extinguish the fire from upwind. Cut off the gas supply. **Cool the container; if possible, move it away from the fire to an open area. In the event of phosgene leakage, trace amounts can be dispersed using steam, while larger amounts can be washed away with liquid ammonia spray. Fire extinguishing agents: fogged water, dry powder, carbon dioxide. 　　Additional note: Phosgene is highly toxic and a strong irritant ； Asphyxiating gases. Inhalation of phosgene causes pulmonary edema ； Pneumonia and other conditions pose a risk of death. 　　Emergency measures for phosgene leaks: Evacuate people from the contaminated area to an upwind location promptly and isolate it immediately; for small leaks, isolate a distance of 150 meters, and for large leaks, isolate a distance of 450 meters, strictly restricting access. It is recommended that emergency responders wear self-contained positive-pressure breathing apparatus and protective clothing. Enter the site from the upwind side. Seal the source of leakage as much as possible. Ensure proper ventilation to accelerate diffusion. Neutralize by spraying ammonia water or other dilute alkaline solutions. Construct dikes or dig pits to contain the large amount of wastewater generated. Leaking containers must be properly handled, repaired, and inspected before being reused. 　　Phosgene is highly hydrolyzable; even in cold water, its hydrolysis occurs at a rapid rate. Water sources, water-containing foods, and substances that absorb water easily will not become contaminated. Phosgene reacts rapidly with ammonia to produce mainly non-toxic substances such as urea and ammonium chloride; therefore, concentrated ammonia can be used to disinfect phosgene. Phosgene reacts with organic amines to produce a white precipitate of diphenylurea and aniline hydrochloride. This reaction can be used to test phosgene. Phosgene is rapidly decomposed in an alkaline solution to form non-toxic substances. Various bases and alkaline substances can be used to disinfect phosgene. 　　Additional note: Phosgene has an odor similar to that of green apples; it is highly toxic. Inhaling it causes liquefaction in the lungs, and excessive inhalation can lead to death from asphyxiation. 　　Long-term experiments on human exposure to trace amounts of phosgene have shown that this gas can cause weight gain; as a result, workers in factories that produce phosgene may experience weight gain, which is related to their exposure to these trace amounts of phosgene.

This issue is quite complex; the explanation above is quite good