3-Pentanone CAS 96-22-0

Product Information

Toxicity and Ecological Information of 3-Pentanone

1. Skin/Eye Irritation

• Open irritation test (rabbit, skin): 410 mg → mild reaction.
• Draize test (rabbit, skin): 500 mg/24h → mild irritation.
• Draize test (rabbit, eyes): 50 mg → moderate irritation.
• Draize test (rabbit, eyes): 100 mg/24h → moderate irritation.

2. Acute Toxicity

• Rat, oral LD₅₀: 2140 mg/kg
• Rat, inhalation LCLo: 8000 ppm / 4 h
• Rat, intraperitoneal LDLo: 1250 mg/kg
• Mouse, oral LD₅₀: 3100 mg/kg
• Mouse, intravenous LD₅₀: 513 mg/kg
• Rabbit, dermal LD₅₀: 20 mL/kg
• Acute Toxicity Reference: Oral LD₅₀ (rat) = 2140 mg/kg; Dermal LD₅₀ (rabbit) = 20,000 mg/kg

3. Mutagenicity

• Yeast gene conversion and mitotic recombination test: 14,800 ppm
• Yeast sex chromosome loss and nondisjunction test: 14,800 ppm

4. Exposure Limits

• Odor threshold concentration: 33 mg/m³
• Maximum permissible workplace concentration (U.S.): 705 mg/m³

5. Subacute and Chronic Toxicity

Rats administered 250 mg or 454 mg/(kg·day) via drinking water for 13 months showed only slight body weight reduction, with no other abnormal effects observed.

Chemical Properties

• Highly flammable, vapor forms explosive mixtures with air.
• Reacts violently with oxidizing agents.
• Vapor is heavier than air and may accumulate in low areas.

Applications

• Used as an organic solvent (in paints, inks, coatings).
• Intermediate for pharmaceutical synthesis.
• Raw material in organic synthesis.
• Used in fragrance and flavor manufacturing.

Safety & Handling

Storage:

• Store in a cool, well-ventilated place.
• Keep container tightly closed.
• Keep away from heat, sparks, flames, and oxidizing agents.
• Explosion-proof equipment required.
• Emergency handling materials must be available in the storage area.

Transportation:

• Transport according to regulations.
• Vehicles must be equipped with fire-fighting and emergency equipment.
• Recommended transport during early morning or evening in summer.
• Protect against static electricity, sunlight, and rain.
• Follow designated transport routes.

Operation:

• Use only in well-ventilated areas with closed systems.
• Trained personnel only.
• Full protective equipment required.
• Prevent fire, static discharge, and leaks.
• Handle with care, avoid impact.

Protective Measures:

• Respiratory, eye, body, and hand protection required.
• Avoid prolonged or repeated exposure.

First Aid:

• Skin contact: Wash with soap and water.
• Eye contact: Rinse with plenty of water, seek medical advice.
• Inhalation: Move to fresh air, give oxygen if needed, seek medical help.
• Ingestion: Rinse mouth, do not induce vomiting, seek immediate medical attention.

Firefighting Measures:

• Remove containers from fire area if safe.
• Cool containers with water spray.
• Use alcohol-resistant foam, dry chemical, or CO₂ for firefighting.

Spill Response:

• Evacuate personnel, isolate area.
• For small spills: absorb with activated carbon or inert absorbents.
• For large spills: build dikes, collect for recycling or safe disposal

3-Pentanone (CAS: 96-22-0) Preparation Methods

1. Oxidation of 3-pentanol

• 3-Pentanone can be obtained by oxidation of 3-pentanol.
• The oxidation reaction is carried out at 90 °C.
• After the reaction, the mixture is filtered and then fractionally distilled.
• The fraction collected at 101–104 °C is the final product.

2. Oxidation using sodium dichromate

• Another common preparation method involves oxidizing 3-pentanol with sodium dichromate in the presence of sulfuric acid at 90 °C.
• Upon completion of the reaction, the product is obtained by distillation.

Purification Methods:

• Dry with barium oxide or calcium sulfate, followed by distillation.
• Alternatively, reflux with calcium chloride for 2 hours, then add fresh CaCl₂, leave overnight, filter, and distill.
• For high-purity 3-pentanone:
  • Use a distillation column with 100 theoretical plates under 93.33 kPa and a reflux ratio of 100:1.
  • The distillate is subjected to fractional crystallization, followed by redistillation with calcium hydroxide.
  • Purity can reach 99.95% ± 0.01%.

3. Preparation with manganese carbonate–pumice catalyst

• Catalyst preparation:
  • Dissolve 70 g (0.35 mol) MnCl₂·4H₂O in 100 mL water.
  • Under stirring, slowly add a solution of 38 g (0.35 mol) anhydrous Na₂CO₃ in 120 mL water.
  • Filter the resulting manganese carbonate precipitate and wash thoroughly.
  • Transfer the solid to a large evaporating dish, add water to form a paste, and mix with pumice (4–8 mesh) so that most of the paste adheres to the pumice.
• Catalyst activation:
  • Under nitrogen protection, heat the catalyst in a tube furnace at 360–400 °C for 8 hours, converting MnCO₃ into MnO.
• Reaction:
  • At 350–400 °C, add 740 g (10 mL) of redistilled propionic acid dropwise to the catalyst using a dropping funnel (rate: ~30 drops/min).
  • Addition takes about 48–72 hours.
  • The distillate separates into two layers: organic and aqueous.
  • The aqueous layer is saturated with solid K₂CO₃, then the organic layer is separated and combined.
  • Treat with solid K₂CO₃ to remove residual acid and water, filter, and distill.
  • Collect the fraction at 101–103 °C, yielding 250 g of 3-pentanone (29% yield).