N- Hexane

n-Hexane is a saturated aliphatic hydrocarbon belonging to the alkane family, consisting of a straight carbon chain. In its pure form, it is a colorless liquid with a mild odor, high volatility, and extreme flammability. It is mainly obtained from the distillation of light naphtha fractions and crude oil derivatives.
n-Hexane is one of the most widely used non-polar organic solvents in various industries, particularly in chemical, food, pharmaceutical, and laboratory processes.

Chemical Formula and Structure of n-Hexane

The molecular formula of n-Hexane is C₆H₁₄, and its molar mass is 86.18 g/mol.
Its structure consists of a linear chain of six carbon atoms connected by single bonds, each carbon atom being saturated with hydrogen atoms.

The structural formula is represented as CH₃–(CH₂)₄–CH₃.

The IUPAC name of the compound is Hexane. For the linear isomer, the prefix “n-” (normal) is added, making it n-Hexane.
It is one of several hexane isomers, along with 2-methylpentane and 3-methylpentane, which are also found in industrial hexane mixtures.

Physical and Chemical Properties of n-Hexane

Industrial Applications of n-Hexane

n-Hexane is one of the most common non-polar organic solvents used in various industries:

Food Industry

• Used for extraction of vegetable oils from seeds such as soybean, canola, cottonseed, and sunflower.

• Applied in fat separation during food processing (industrial scale only — residual solvent must be completely removed).

Pharmaceutical and Chemical Industries

• Used as a solvent in the synthesis of pharmaceutical compounds.

• Extraction of bioactive compounds from plants.

• Washing and crystallization of active pharmaceutical ingredients (APIs).

Rubber and Adhesive Industries

• Acts as a diluent for industrial adhesives.

• Solvent for rubber, elastomeric polymers, and certain resins.

Electronics and Laboratory Applications

• Used as a surface cleaner for sensitive electronic components.

• Employed for glassware cleaning under controlled, well-ventilated conditions.

Advantages of n-Hexane

• Excellent solvent power for non-polar organic compounds such as oils, fats, and resins.

• Rapid evaporation and high volatility, enabling quick drying of surfaces.

• Wide availability and relatively low cost on an industrial scale.

• Colorless and low-odor at low concentrations.

• Leaves minimal residue upon complete evaporation.

Disadvantages of n-Hexane

Despite its advantages, n-Hexane has significant drawbacks that must be carefully managed in industrial and laboratory use:

• Highly flammable — vapors can easily ignite at room temperature with even small sparks.

• Neurotoxic (neurotoxicant) under chronic exposure, especially in occupational settings — may cause peripheral polyneuritis, muscle weakness, and numbness in hands and feet.

• High environmental hazard in case of spillage or improper disposal; can contaminate soil and surface water.

• Very low miscibility with water, making removal from aqueous environments difficult.

• Potential for bioaccumulation with prolonged environmental exposure.

Safety and Storage of n-Hexane

GHS Hazard Classification:

• H225: Highly flammable liquid and vapor

• H336: May cause drowsiness or dizziness

• H304: May be fatal if swallowed and enters airways

Personal Protective Equipment (PPE):

• Nitrile gloves, safety goggles, half-face respirator with organic vapor filter (A-type), and solvent-resistant lab coat.

Ventilation:

• Mandatory — must be used in a chemical fume hood or well-ventilated area.

Safe Storage:

• Store in metal or HDPE solvent-resistant containers, tightly sealed.

• Keep in a cool, dry, well-ventilated area, away from heat sources, flames, sparks, and direct sunlight.

Emergency Measures:

• In case of spillage, cover the area with absorbent material (e.g., sand, vermiculite), and ensure immediate ventilation.

• Skin and eye contact: Rinse immediately with plenty of water for at least 15 minutes.

• Ingestion: Do not induce vomiting; seek immediate medical attention.