Butanol

Product Details

CasNo： 71 - 36 - 3

MF： C₄H₁₀O

Appearance： liquid

Purity： 99.5% Min

1. Basic Information​

1. Chinese Name: 正丁醇​

2. English Name: 1 - Butanol, n - Butanol, n - Butyl alcohol​

3. Chemical Formula: C₄H₁₀O, with the structural formula CH₃(CH₂)₃OH​

4. CAS Registry Number: 71 - 36 - 3​

5. EINECS Registry Number: 200 - 751 - 6​

6. Molecular Weight: 74.12​

2. Physicochemical Properties​

1. Appearance: A colorless, transparent liquid with a characteristic odor, similar to the smell of wine.​

2. Melting Point: - 89.8 °C​

3. Boiling Point: 117.7 °C​

4. Density: Relative density (water = 1) is 0.8109 (at 20/20 °C); relative vapor density (air = 1) is 2.55​

5. Solubility: Slightly soluble in water. At 20 °C, its solubility in water is 7.7% (by weight), and the solubility of water in n - butanol is 20.1% (by weight). It is miscible with ethanol, ether, and many other organic solvents. It can dissolve alkaloids, camphor, dyes, rubber, ethyl cellulose, resin salts (calcium salts, magnesium salts), fats, waxes, and a variety of natural and synthetic resins.​

6. Saturated Vapor Pressure: 0.739 kPa (at 20 °C)​

7. Heat of Combustion: - 2673.2 kJ/mol​

8. Critical Temperature: 289.85 °C​

9. Critical Pressure: 4.414 MPa​

10. Octanol/Water Partition Coefficient: 0.88​

11. Flash Point: 29 °C (closed - cup)​

12. Ignition Temperature: 355 - 365 °C​

13. Explosive Limit: 1.4% - 11.3% (by volume)​

14. Viscosity: 2.95 mPa·s (at 20 °C)​

15. Heat of Vaporization: 43.86 kJ/mol​

16. Heat of Fusion: 125.2 kJ/kg​

17. Heat of Formation: - 246.67 kJ/mol​

18. Specific Heat Capacity: 2.33 kJ/(kg·K) (at 20 °C, at constant pressure)​

19. Conductivity: 9.12×10⁻⁹ S/m​

20. Thermal Conductivity: 16.75 W/(m·K) (at 20 °C)​

21. Coefficient of Cubical Expansion: 0.00095 K⁻¹ (at 20 °C)​

22. Relative Density (at 20 °C, 4 °C): 0.8097​

23. Relative Density (at 25 °C, 4 °C): 0.8060​

24. Refractive Index at Room Temperature (n²⁵): 1.3971​

25. Critical Density: 0.271 g·cm⁻³​

26. Critical Volume: 274 cm³·mol⁻¹​

27. Critical Compressibility Factor: 0.258​

28. Acentric Factor: 0.595​

3. Production Methods​

1. Fermentation Method: Historically, butanol was mainly produced by hydrolysis and fermentation of potatoes, grains, or sugars. The fermentation broth contains about 54.8% - 58.5% n - butanol, 30.9% - 33.7% acetone, and 7.8% - 14.2% ethanol. With the development of petrochemical industry, this method has been gradually phased out due to disadvantages such as high raw material consumption, long production cycle, and low yield. However, in some specific scenarios, such as the continuous innovation of biotechnologies, the production of n - butanol by fermentation of renewable resources still has certain research and application value.​

2. Oxo - Synthesis of Propylene:​

• High - Pressure Method: Propylene, carbon monoxide, and hydrogen react on a catalytic bed. The catalyst is cobalt salt adsorbed on zeolite or fatty acid cobalt. The reaction temperature is 130 - 160 °C, and the reaction pressure is 20 - 25 MPa. The reaction produces n - butyraldehyde and isobutyraldehyde. After distillation for separation, n - butyraldehyde is catalytically hydrogenated to obtain n - butanol. The ratio of n - butyraldehyde to isobutyraldehyde produced is about 3.​

• Low - Pressure Method: n - Butanol is synthesized from propylene, carbon monoxide, and water in one step. The reaction temperature is 100 - 104 °C, and the pressure is 1.5 MPa. A mixture of iron pentacarbonyl, n - butylpyrrolidine, and water is used as the catalyst. However, the single - pass conversion rate of propylene is relatively low, only 8% - 10%. Currently, due to the advantages of readily available raw materials (propylene, etc. from petrochemical industry, with relatively rich resources), relatively reduced carbonylation process pressure, increased ratio of n - butanol to isobutanol in the product, and the ability to co - produce or specifically produce 2 - ethylhexanol, the oxo - synthesis of propylene has become the most important production method for n - butanol.​

3. Aldol Condensation of Acetaldehyde: Using acetaldehyde as the raw material, adding a dilute alkali solution, 2 - hydroxybutyraldehyde is obtained at a temperature below 20 °C. When the reaction reaches 50%, it is terminated. The alkali is neutralized with acid, and the unreacted acetaldehyde is recovered. 2 - hydroxybutyraldehyde is extracted from the bottom of the tower, and then dehydrated to crotonaldehyde at 105 - 137 °C using acidic catalysts such as sulfuric acid and acetic acid. Then, it is hydrogenated to obtain crude n - butanol and butyraldehyde at 160 - 240 °C using a copper - complex catalyst, and finally refined to obtain the finished product. This method has a relatively complex process and high cost, and is not as widely used in industry as the oxo - synthesis of propylene.​

4. Other Methods: n - Butanol is also a by - product in the production of higher fatty alcohols from ethylene. In addition, there are some new methods in the research stage, aiming to improve the production efficiency of n - butanol, reduce costs, and reduce environmental impact.​

4. Main Applications​

1. Plasticizer Manufacturing: It is a key raw material for manufacturing n - butyl ester plasticizers of phthalic acid, aliphatic dibasic acids, and phosphoric acid. These plasticizers are widely used in various plastic and rubber products. They can effectively improve the flexibility, plasticity, and processing performance of plastic products. For example, in polyvinyl chloride (PVC) plastics, plasticizers such as dibutyl phthalate (DBP) derived from n - butanol are widely used, enabling PVC to be made into various soft plastic products such as plastic films and artificial leather. In rubber products, it can also improve the processing performance and physical properties of rubber.​

2. Raw Material for Organic Synthesis: In the field of organic synthesis, n - butanol is an important raw material for preparing butyraldehyde, butyric acid, butylamine, and butyl lactate. Through oxidation reactions, n - butanol can be converted into butyraldehyde, and butyraldehyde can be further oxidized to butyric acid. Reacting with ammonia can prepare butylamine, and reacting with lactic acid can generate butyl lactate. These products are widely used in many industries such as pharmaceuticals, flavors, and pesticides. For example, butyric acid can be used to synthesize flavors and drugs, and butylamine can be used to produce pesticides and surfactants.​

3. Solvent Applications:​

• Coating and Ink Industry: It is an excellent solvent for a variety of coatings. It can dissolve resin, pigment, and other components, giving the coating good fluidity and coating performance, and helping the coating form a uniform and smooth film during the drying process. In nitrocellulose lacquers, n - butanol is often used as a cosolvent to improve the drying performance and gloss of the lacquer. In printing inks, it can be used as a solvent to dissolve the colorants and resins in the ink, giving the ink good printing adaptability and ensuring printing quality.​

• Extraction of Fats, Oils, Drugs, and Flavors: Utilizing its solubility in fats, oils, drugs (such as antibiotics, hormones, and vitamins), and flavors, n - butanol can be used as an extractant. In the extraction of natural drugs, it can extract the active ingredients from plant or animal tissues. In the flavor industry, it is used to extract and separate flavor components from natural flavor raw materials, improving the purity and quality of flavors.​

• Other Solvent Uses: It can be used as a solvent for organic dyes, helping the dyes to disperse uniformly in the solution and achieving a good dyeing effect. In the laboratory, it can also be used to separate potassium perchlorate and sodium perchlorate, as well as to separate sodium chloride and lithium chloride. It is also used to wash the precipitate of sodium uranyl zinc acetate.​

4. Pharmaceutical Field: In the pharmaceutical industry, in addition to being used as an extractant for drug extraction, it can also be used as a solvent or excipient in pharmaceutical preparations. In the preparation of some drugs, n - butanol is needed to dissolve the drug components, promoting the stability and uniformity of the drug. In some topical preparations, n - butanol can also be used as a solvent or penetration enhancer.​

5. Cosmetics Industry: In cosmetics, it is mainly used as a cosolvent in products such as nail polishes. Together with main solvents such as ethyl acetate, it helps to dissolve the colorants and adjust the evaporation rate and viscosity of the solvent, making the nail polish spread more evenly, dry at an appropriate speed, and less likely to crack. The addition amount is generally about 10%.​

6. Other Applications: In screen printing, it can be used as an antifoaming agent for ink formulation, effectively eliminating bubbles in the ink and improving the quality and clarity of screen printing. It can be used in baked foods, puddings, candies, etc., as a solvent or additive for flavors, improving the flavor and taste of foods. In some industrial processes, it can also be used as a dehydrating agent and anti - emulsifying agent.​

5. Packaging and Storage​

1. Packaging:​

• Usually, clean and dry railway tank cars can be used for large - scale transportation and packaging, which is suitable for long - distance and large - volume transportation of n - butanol.​

• Galvanized iron drums are also a common packaging method. The net weight of each drum is generally 150 kg, 160 kg, 170 kg, or other specifications. They are convenient for handling and storage and are suitable for different - scale usage scenarios. The packaging containers must be strictly sealed to prevent the volatilization and leakage of n - butanol.​

• Small - opening steel drums, ampoules in ordinary wooden boxes, and other packaging forms can also be used to meet special needs or the packaging of small - quantity products.​

2. Storage:​

• It should be stored in a dry and well - ventilated warehouse, and the warehouse temperature should not exceed 35 °C. A high - temperature environment will accelerate the volatilization of n - butanol and increase safety risks.​

• Keep away from fire sources and flammable substances. n - Butanol is flammable, and its vapor can form an explosive mixture with air. It can cause combustion and explosion when exposed to open flames or high heat. Therefore, smoking is strictly prohibited in the storage area, and a safe distance should be maintained from other flammable substances.​

• Store separately from oxidants and acids. n - Butanol may react violently with strong oxidants and strong acids, causing danger.​

• The storage area should be equipped with corresponding types and quantities of fire - fighting equipment and leakage emergency treatment equipment to respond promptly in case of accidents.​

6. Safety Information​

1. Toxicity: n - Butanol is of low toxicity. Its anesthetic effect is stronger than that of propanol. Repeated contact with the skin can lead to bleeding and necrosis. Its toxicity to humans is about three times that of ethanol. Its vapor irritates the eyes, nose, and throat. At a concentration of 75.75 mg/m³, it makes people feel uncomfortable. However, due to its high boiling point and relatively low volatility, except for high - temperature use, the risk is relatively low under normal circumstances. The oral LD₅₀ for rats is 4.36 g/kg. The olfactory threshold concentration is 33.33 mg/m³.​

2. Safety Measures:​

• Engineering Controls: The production and use sites of n - butanol should be provided with good ventilation facilities. Local exhaust or general ventilation should be adopted to reduce the concentration of n - butanol vapor in the air, avoiding reaching the explosive limit and causing health hazards to personnel.​

• Personal Protection: Operators should wear appropriate protective equipment when in contact with n - butanol. For example, wear protective gloves (such as nitrile gloves) to prevent direct skin contact with n - butanol, avoid skin dryness, cracking, and even absorption and poisoning. Wear safety goggles or face shields to protect the eyes from the irritation and damage of n - butanol vapor or liquid. In environments where high - concentration n - butanol vapor may be encountered, wear gas masks, such as self - contained breathing apparatus (half - mask).​

3. Emergency Response:​

• Leakage Emergency Response: In case of n - butanol leakage, quickly evacuate the personnel in the leakage - contaminated area to a safe area and isolate it, strictly restricting access. Cut off the fire source. It is recommended that emergency responders wear self - contained positive - pressure breathing apparatus and fire - resistant protective clothing. Try to cut off the leakage source as much as possible to prevent it from entering sewers, flood discharge ditches, and other restricted spaces. For small - scale leakage, it can be absorbed with activated carbon or other inert materials, or it can be washed with a large amount of water, and the diluted washing water is discharged into the wastewater system. For large - scale leakage, build dikes or dig pits to contain it; cover it with foam to reduce vapor hazards. Transfer it to a tank truck or a special collector with an explosion - proof pump for recycling or transportation to a waste treatment site for disposal.​

• First - Aid Measures:​

• Inhalation: Quickly leave the site and move to an area with fresh air. Keep the respiratory tract unobstructed. If breathing is difficult, give oxygen. If breathing stops, immediately perform artificial respiration and seek medical attention in time.​

• Skin Contact: Immediately remove contaminated clothing and thoroughly wash the skin with soapy water and clean water. Seek medical advice to check for further damage.​

• Eye Contact: Immediately lift the eyelids and thoroughly rinse the eyes with a large amount of flowing water or normal saline for at least 15 minutes. Seek medical treatment for professional handling.​

• Ingestion: Drink plenty of warm water, induce vomiting, and seek medical treatment for gastric lavage and other treatments.