Butyl Acetate Handling & Lab Use Guidelines | Aladdin

Butyl acetate is a widely used ester solvent in research and industrial laboratories, valued for its moderate polarity, pleasant fruity odor, and broad compatibility with resins, coatings, and extraction processes.

Chemical Name

n-Butyl acetate (butyl ethanoate)

CAS Number

123-86-4

Molecular Formula

C₆H₁₂O₂

Molecular Weight

116.16 g/mol

Boiling Point

126–127 °C at 760 mmHg

Flash Point

22–24 °C (closed cup)

Density

~0.882 g/mL at 20 °C

Miscibility

Miscible with most organic solvents; slightly soluble in water (~7 g/L at 20 °C)

Chemical Properties and Research Applications

Butyl acetate (CAS 123-86-4) is an ester formed by the Fischer esterification of acetic acid and 1-butanol. It presents as a clear, colorless, flammable liquid with a characteristic fruity odor. Its moderate Hildebrand solubility parameter (~8.5 cal^1/2·cm^-3/2) makes it effective for dissolving a broad range of nonpolar to moderately polar solutes, including nitrocellulose, polyacrylates, epoxy resins, and natural waxes.

In research settings, butyl acetate is routinely employed in:

• Liquid–liquid extraction: extraction of antibiotics, natural products, and lipophilic analytes from aqueous matrices.
• Chromatography: as a mobile-phase component or sample diluent in normal-phase HPLC and TLC.
• Polymer and coating research: dissolution of film-forming polymers and evaluation of coating formulations.
• Semiconductor and microelectronics fabrication: photoresist stripping and wafer cleaning applications where its moderate evaporation rate is advantageous.
• Flavor and fragrance analysis: as a reference standard solvent and extraction medium, given its own GRAS status as a food flavoring agent.

Its moderate evaporation rate (relative evaporation rate ~1.0 relative to n-butyl acetate as reference) and low water miscibility simplify downstream workup and solvent removal steps.

Safety, Hazards, and Regulatory Classification

Butyl acetate is classified as a flammable liquid (Category 3) under GHS/UN regulations. Researchers must understand its key hazard profile before use:

• Flammability: Flash point 22–24 °C (closed cup); keep away from open flames, hot surfaces, and static discharge. Store and handle below the flash point temperature where possible.
• Vapor hazard: Vapors are heavier than air (vapor density ~4.0) and can accumulate in low-lying areas and drains. The lower explosive limit (LEL) is approximately 1.7% v/v.
• Inhalation: Exposure to high vapor concentrations causes headache, dizziness, and mucous membrane irritation. The OSHA permissible exposure limit (PEL) is 150 ppm (TWA); ACGIH TLV-TWA is 50 ppm. Use only in well-ventilated areas or under a fume hood.
• Skin and eye contact: Prolonged skin contact may cause defatting and irritation. Splashes to eyes cause irritation; wear chemical splash goggles and solvent-resistant gloves (nitrile ≥0.4 mm or neoprene recommended).
• GHS Pictograms: Flame, Exclamation mark.
• Signal word: Warning.
• UN Number: UN 1123 (Butyl acetates); Packing Group III.

Consult the current Safety Data Sheet (SDS) supplied with Aladdin Scientific product B1530105B for jurisdiction-specific regulatory information and up-to-date exposure limits before laboratory use.

Storage, Handling, and Purity Selection

Storage recommendations:

• Store in a tightly sealed container in a cool (≤25 °C), dry, well-ventilated flammable-materials storage cabinet, away from heat sources, oxidizing agents, strong bases, and strong acids.
• Ground and bond metal containers during transfer to prevent static ignition.
• Use explosion-proof electrical equipment in storage areas.
• Shelf life is typically ≥24 months when stored properly under inert atmosphere; monitor for hydrolysis (acetic acid odor indicates degradation).

Handling best practices:

• Always work under a certified fume hood or with local exhaust ventilation.
• Use solvent-resistant tubing (PTFE or stainless steel preferred) for transfers.
• Minimize container opening time to reduce vapor generation.
• Dispose of waste solvent according to local hazardous-waste regulations; do not pour down the drain.

Purity grade selection guide:

• Technical grade: Suitable for cleaning, degreasing, and preparative extractions where trace impurities are not critical.
• ACS reagent / ≥99% purity: Recommended for analytical chemistry, chromatographic applications, and synthesis where reproducibility is essential.
• Anhydrous / HPLC grade: Required for moisture-sensitive reactions and LC-MS applications where water content and UV transparency must be controlled.

Aladdin Scientific product B1530105B provides a reliable purity specification suited for research-grade applications; consult the product certificate of analysis (CoA) for lot-specific purity, water content, and GC assay data.

Waste Disposal and Environmental Considerations

Butyl acetate is biodegradable under aerobic conditions; however, it must not be discharged to municipal sewers or surface water systems in laboratory quantities due to its aquatic irritation potential and organic load contribution.

Recommended disposal procedure:

1. Collect waste butyl acetate in clearly labeled, solvent-compatible (HDPE or glass) waste containers designated for halogen-free organic solvents.
2. Keep separate from halogenated solvents to facilitate incineration and solvent recovery programs.
3. Arrange collection through a licensed hazardous-waste contractor in compliance with local environmental regulations (e.g., EPA 40 CFR in the US; EU Waste Framework Directive).
4. Spills on the bench should be absorbed with inert material (vermiculite, dry sand, or commercial absorbent) and transferred to a labeled waste container; avoid using paper towels in large-spill situations due to fire risk.

Environmental fate: butyl acetate hydrolyzes to 1-butanol and acetic acid in aqueous environments. Both products are naturally occurring and subject to rapid microbial degradation. Log K_ow ≈ 1.78 indicates low bioaccumulation potential.

Frequently asked questions

Can butyl acetate be used as a substitute for ethyl acetate in chromatography?

Butyl acetate can substitute for ethyl acetate in many normal-phase TLC and column chromatography applications; it is slightly less polar and has a higher boiling point (127 °C vs. 77 °C), which slows evaporation and can improve resolution of certain nonpolar analytes. However, its higher boiling point makes fraction concentration more time-consuming, and its UV cutoff (~254 nm) should be checked against the detector wavelength. Always verify mobile-phase ratios empirically when switching solvents.

What gloves provide adequate protection when handling butyl acetate?

Nitrile gloves with a minimum thickness of 0.4 mm or neoprene gloves are recommended for routine short-term contact with butyl acetate. Thin disposable nitrile gloves (0.1 mm) offer only splash protection and should be changed immediately upon contamination. Natural latex and PVC gloves provide poor resistance and are not recommended. For prolonged or immersion-type contact, laminated barrier gloves (e.g., Silver Shield/4H) should be used.

How should I handle a butyl acetate spill in the laboratory?

Immediately eliminate all ignition sources and ventilate the area. For small spills (≤1 L), absorb with inert material such as vermiculite or dry sand, then sweep into a labeled waste container. For larger spills, evacuate non-essential personnel, use appropriate respiratory protection (organic vapor respirator), and prevent liquid from entering drains or confined spaces. Dispose of collected waste as hazardous solvent waste. Report significant spills according to your institution's chemical emergency response plan.

Does butyl acetate absorb moisture from the air, and does this affect its performance?

Butyl acetate has limited hygroscopicity compared with THF or acetone; however, repeated opening of containers in humid environments can introduce measurable moisture over time. For moisture-sensitive applications such as peptide synthesis or anhydrous reactions, use anhydrous-grade butyl acetate and store under an inert gas (nitrogen or argon) cap. Check the CoA for water content (Karl Fischer titration value) when purchasing.

References

1. Lide, D.R. (Ed.) CRC Handbook of Chemistry and Physics, 97th Edition. CRC Press, Boca Raton, FL. Physical property data for butyl acetate.
2. Occupational Safety and Health Administration (OSHA). Occupational Exposure Limits: Butyl acetate (n-Butyl acetate). 29 CFR 1910.1000 Table Z-1.
3. American Conference of Governmental Industrial Hygienists (ACGIH). Threshold Limit Values for Chemical Substances and Physical Agents. n-Butyl acetate TLV-TWA 50 ppm.
4. United Nations. UN Recommendations on the Transport of Dangerous Goods – Model Regulations, 22nd Revised Edition. UN No. 1123, Butyl acetates, Class 3, PG III.
5. Riddick, J.A.; Bunger, W.B.; Sakano, T.K. Organic Solvents: Physical Properties and Methods of Purification, 4th Edition. Wiley-Interscience, 1986. Solubility and physicochemical data for butyl acetate.

Products are supplied for research and development use only. Not for use in humans, animals, diagnosis, or therapy.