What is a thiol?
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In the sulfur recovery process, what is thiol?
It should be a thiol. The structure is like: R-SH
Thiol National standard code: 31034 CAS number: 75-08-1 Chinese name: Ethyl mercaptan English name: Ethyl mercaptan； ethanethiol Alternative name: ethyl sulfide ； Methanethiol Molecular formula C2H6S ； CH3CH2SH: Appearance and properties – Colorless liquid with a strong garlic-like odor. Molecular weight: 62.13. Vapor pressure: 53.32 kPa at 17.7°C. Flash point: -45°C. Melting point: -147°C. Boiling point: 36.2°C. Solubility: Slightly soluble in water; more soluble in ethanol, ether, and most other organic solvents. Density: Relative density (water=1): 0.84 ； Relative density (air=1): 2.14. Stability: Stable. Hazard symbol: 7 (flammable liquid with low flash point). Primary uses: As a stabilizer for adhesives and as an intermediate in chemical synthesis. 2. Impact on the environment: I. Health hazards: Routes of exposure: inhalation, ingestion, dermal absorption. Health hazards: This product primarily acts on the central nervous system. Inhaling low concentrations of vapor can cause headaches and nausea ； A higher concentration results in **effect**. High concentrations can cause respiratory paralysis and death. Victims of poisoning may experience vomiting and diarrhea, as well as protein, tubules, and hematuria in the urine. II. Toxicological Data and Environmental Behavior Acute toxicity: LD50 682 mg/kg (oral, rats) ； LC50: 11227 mg/m3, 4 hours (inhalation in rats). Hazardous properties: Its vapors can form explosive mixtures with air. It is highly flammable and explosive when exposed to open flames or high temperatures. It reacts violently upon contact with oxidizers. Contact with acids and acid mist produces toxic gases. Reacts with water and water vapor to release toxic or flammable gases. It reacts violently with calcium hypochlorite and calcium hydroxide. Its vapor is heavier than air, allowing it to spread over considerable distances at lower levels; it can catch fire and reignite when exposed to an open flame. In the event of high temperatures, the pressure inside the container increases, posing a risk of cracking and explosion. Combustion (decomposition) products: carbon monoxide, carbon dioxide, sulfur oxides. 3. On-site emergency monitoring methods: Portable gas chromatography method
4. Laboratory monitoring methods: Gas chromatography method – “Methods for determining harmful substances in air” (2nd edition), compiled by Hang Shiping; P-dimethylaniline colorimetric method – “Methods for determining harmful substances in air” (2nd edition), compiled by Hang Shiping
5. Environmental standards: The maximum allowable concentration of harmful substances in workshop air in the former Soviet Union is 1 mg/m3
6. Emergency response measures: I. Emergency response to leaks: Quickly evacuate people from the area contaminated by the leak to a safe area, and isolate that area while strictly restricting access. Cut off the source of fire. It is recommended that emergency responders wear self-contained positive-pressure breathing apparatus and fire protection clothing. Seal the source of leakage as much as possible. Prevent entry into confined spaces such as sewers and drainage ditches. Minor leaks: Absorb with activated carbon or other inert materials. It can also be rinsed with a large amount of water, and the diluted wash water is then discharged into the wastewater system. Large-scale leakage: Build dikes or dig pits to contain it ； Cover with foam to reduce vapor hazards. Transfer to a tank truck or specialized collector using an explosion-proof pump, and recycle it or transport it to a waste disposal facility for disposal. Waste disposal method: Incineration. The gases emitted from the incinerator furnace bed must be washed with an alkaline solution. II. Protective Measures Respiratory protection: When the concentration of the substance in the air exceeds safe levels, a self-priming filter-type gas mask (half-mask) should be worn. It is recommended to wear an air respirator if necessary. Eye protection: Wear chemical safety goggles. Body protection: Wear anti-static work clothes. Hand protection: Wear rubber gloves. Others: Smoking is strictly prohibited at the work site. After work, take a shower. ** Pay attention to personal hygiene. III. First aid measures Skin contact: Remove the contaminated clothing and thoroughly wash the skin with soapy water and clean water. Eye contact: Lift the eyelids and rinse with flowing water or saline. Seek medical attention. Inhalation: Quickly move to a place with fresh air. Keep the airways clear. If there is difficulty breathing, administer oxygen. If breathing stops, perform artificial respiration immediately. Seek medical attention. Ingestion: Drink plenty of warm water, induce vomiting, and seek medical attention. Fire extinguishing method: Move the container away from the fire as much as possible to an open area. **Keep the containers at the fire site cooled down until the fire is extinguished. If a container in a fire has changed color or noises are coming from its safety pressure relief device, it must be evacuated immediately. Extinguishing agents: alcohol-resistant foam, dry powder, carbon dioxide, sand. Using water to extinguish the fire is ineffective. Organic compounds in which a hydrothio or thio–SH group is connected to an aliphatic hydrocarbon group. Organic compounds in which a thiol group is directly attached to an aromatic nucleus are called thiophenols. Present in crude oil, usually various thiols with ethanethiol as the main component. Furthermore, allylthiol is present in mustard oil, while amino acids containing a thiol group, such as cysteine, are found in proteins. The properties of thioalcohols and thiophenols are similar to those of alcohols and phenols. Both thioethers and thiophenes have a strong odor; ethanethiol can be detected at a concentration of 50 billionths in the air. Thiols and thioethers are weak acids; their acidity is stronger than that of their corresponding hydroxy compounds, but weaker than that of acetic acid. They react with mercuric chloride to form insoluble mercury salts, and they can also be oxidized by various oxidizing agents to form disulfides. Thiols can be obtained by a substitution reaction between halides and sodium hydrosulfide, or by reacting halides with thiourea and then treating the product with an alkaline solution. High-temperature catalytic reaction of alcohols with hydrogen sulfide can produce large quantities of inexpensive ethanethiol and butanethiol. Thiophenols are generally prepared by the reduction of aromatic sulfonyl chlorides. Some thioethers and thiophenes can be used as drugs, antidotes, and accelerators for rubber vulcanization, as well as as raw materials for synthesizing fungicides. For example, thiosalicylic acid can be used to synthesize the fungicide ethylmercury salicylate ； 2-Mercaptobenzothiazole can be used as a vulcanization accelerator for rubber ； 2,3-Dimercaprol can be used as an antidote for arsenic poisoning ； 6-mercaptopurine can treat cancer.
4. Laboratory monitoring methods: Gas chromatography method – “Methods for determining harmful substances in air” (2nd edition), compiled by Hang Shiping; P-dimethylaniline colorimetric method – “Methods for determining harmful substances in air” (2nd edition), compiled by Hang Shiping
5. Environmental standards: The maximum allowable concentration of harmful substances in workshop air in the former Soviet Union is 1 mg/m3
6. Emergency response measures: I. Emergency response to leaks: Quickly evacuate people from the area contaminated by the leak to a safe area, and isolate that area while strictly restricting access. Cut off the source of fire. It is recommended that emergency responders wear self-contained positive-pressure breathing apparatus and fire protection clothing. Seal the source of leakage as much as possible. Prevent entry into confined spaces such as sewers and drainage ditches. Minor leaks: Absorb with activated carbon or other inert materials. It can also be rinsed with a large amount of water, and the diluted wash water is then discharged into the wastewater system. Large-scale leakage: Build dikes or dig pits to contain it ； Cover with foam to reduce vapor hazards. Transfer to a tank truck or specialized collector using an explosion-proof pump, and recycle it or transport it to a waste disposal facility for disposal. Waste disposal method: Incineration. The gases emitted from the incinerator furnace bed must be washed with an alkaline solution. II. Protective Measures Respiratory protection: When the concentration of the substance in the air exceeds safe levels, a self-priming filter-type gas mask (half-mask) should be worn. It is recommended to wear an air respirator if necessary. Eye protection: Wear chemical safety goggles. Body protection: Wear anti-static work clothes. Hand protection: Wear rubber gloves. Others: Smoking is strictly prohibited at the work site. After work, take a shower. ** Pay attention to personal hygiene. III. First aid measures Skin contact: Remove the contaminated clothing and thoroughly wash the skin with soapy water and clean water. Eye contact: Lift the eyelids and rinse with flowing water or saline. Seek medical attention. Inhalation: Quickly move to a place with fresh air. Keep the airways clear. If there is difficulty breathing, administer oxygen. If breathing stops, perform artificial respiration immediately. Seek medical attention. Ingestion: Drink plenty of warm water, induce vomiting, and seek medical attention. Fire extinguishing method: Move the container away from the fire as much as possible to an open area. **Keep the containers at the fire site cooled down until the fire is extinguished. If a container in a fire has changed color or noises are coming from its safety pressure relief device, it must be evacuated immediately. Extinguishing agents: alcohol-resistant foam, dry powder, carbon dioxide, sand. Using water to extinguish the fire is ineffective. Organic compounds in which a hydrothio or thio–SH group is connected to an aliphatic hydrocarbon group. Organic compounds in which a thiol group is directly attached to an aromatic nucleus are called thiophenols. Present in crude oil, usually various thiols with ethanethiol as the main component. Furthermore, allylthiol is present in mustard oil, while amino acids containing a thiol group, such as cysteine, are found in proteins. The properties of thioalcohols and thiophenols are similar to those of alcohols and phenols. Both thioethers and thiophenes have a strong odor; ethanethiol can be detected at a concentration of 50 billionths in the air. Thiols and thioethers are weak acids; their acidity is stronger than that of their corresponding hydroxy compounds, but weaker than that of acetic acid. They react with mercuric chloride to form insoluble mercury salts, and they can also be oxidized by various oxidizing agents to form disulfides. Thiols can be obtained by a substitution reaction between halides and sodium hydrosulfide, or by reacting halides with thiourea and then treating the product with an alkaline solution. High-temperature catalytic reaction of alcohols with hydrogen sulfide can produce large quantities of inexpensive ethanethiol and butanethiol. Thiophenols are generally prepared by the reduction of aromatic sulfonyl chlorides. Some thioethers and thiophenes can be used as drugs, antidotes, and accelerators for rubber vulcanization, as well as as raw materials for synthesizing fungicides. For example, thiosalicylic acid can be used to synthesize the fungicide ethylmercury salicylate ； 2-Mercaptobenzothiazole can be used as a vulcanization accelerator for rubber ； 2,3-Dimercaprol can be used as an antidote for arsenic poisoning ； 6-mercaptopurine can treat cancer.
Thiol is: National standard code 31034; CAS number 75-08-1; Chinese name: ethyl mercaptan; English name: ethyl mercaptan； ethanethiol Alternative name: ethyl sulfide ； Methanethiol Molecular formula C2H6S ； CH3CH2SH: Appearance and properties – Colorless liquid with a strong garlic-like odor. Molecular weight: 62.13. Vapor pressure: 53.32 kPa at 17.7°C. Flash point: -45°C. Melting point: -147°C. Boiling point: 36.2°C. Solubility: Slightly soluble in water; more soluble in ethanol, ether, and most other organic solvents. Density: Relative density (water=1): 0.84 ； Relative density (air=1): 2.14 Stability: Stable. Hazard symbol: 7 (flammable liquid with low flash point). Main uses: Used as a stabilizer for adhesives and as an intermediate in chemical synthesis
Who knows what this substance smells like?