Limonene CAS 138-86-3

Limonene – Natural Monoterpene Solvent and Citrus Fragrance for Cosmetics, Perfumery, and Cleaning Products

Basic Information

• CAS Number: 138-86-3

• Molecular Formula: C₁₀H₁₆

• Molecular Weight: 136.23 g/mol

• Synonyms: Dipentene, (±)-Limonene, p-Mentha-1,8-diene

• Appearance: Clear, colorless to pale yellow liquid

• Odor: Fresh, bright citrus, reminiscent of oranges and lemons

• Density: ~0.84 g/cm³ (at 20°C)

• Boiling Point: 176–177°C

• Flash Point: 48°C (flammable)

• Solubility: Insoluble in water; miscible with oils and organic solvents

• Storage: Store in tightly sealed containers in a cool, well-ventilated place, protected from light and heat

Overview
Limonene is a naturally occurring cyclic monoterpene widely distributed in the essential oils of citrus fruits (oranges, lemons, limes, grapefruits). It exists in two enantiomeric forms: D‑limonene (the major form in citrus oils) and L‑limonene (found in mint oils). This versatile compound is valued for its fresh, uplifting citrus aroma and its excellent solvent, degreasing, and antimicrobial properties. It is used across multiple industries, including cosmetics, perfumery, household cleaning, and industrial applications.

Key Properties

• Natural solvent: Effectively dissolves oils, fats, and resins, making it useful in degreasers and paint strippers.

• Fragrance component: Provides a fresh, bright citrus note in perfumes, soaps, shampoos, and lotions.

• Antiseptic: Exhibits mild antibacterial and antifungal activity.

• Volatile: High evaporation rate provides a quick aroma release.

• Biodegradable: Environmentally friendly and derived from renewable citrus sources.

• Penetration enhancer: Improves the absorption of other active ingredients in topical formulations.

Applications

• Cosmetics and personal care: Used as a fragrance ingredient in creams, lotions, shampoos, shower gels, and perfumes; also acts as a natural solvent and penetration enhancer.

• Household products: Added to all‑purpose cleaners, degreasers, and detergents for its cleaning power and fresh scent.

• Industrial: Used as a solvent for paints, coatings, and adhesive removers; also as a degreaser for metal parts.

• Aromatherapy: Diffused for its uplifting and stress‑relieving effects.

• Food industry: Used as a flavoring agent in beverages, confectionery, and baked goods (subject to regulations).

• Agriculture: Used as a natural insect repellent and in biopesticide formulations.

Key Benefits

• Provides a fresh, natural citrus fragrance.

• Effective solvent with excellent degreasing properties.

• Mild antimicrobial activity, enhancing product preservation.

• Biodegradable and derived from renewable resources.

• Enhances the penetration of active ingredients in skin care.

• Compatible with a wide range of cosmetic and industrial ingredients.

• Versatile – suitable for personal care, cleaning, and industrial applications.

Recommended Use
Typical usage levels vary depending on the application:

• Cosmetics and fragrances: 0.1–5.0% as a fragrance or solvent.

• Household cleaners: 1–10% for degreasing and scent.

• For optimal performance, incorporate into the oil phase or add at room temperature.

• Note that limonene is a known allergen; its use in leave‑on products may require labelling according to local regulations.

Safety and Handling

• Limonene is generally recognized as safe (GRAS) for use in food and cosmetics at recommended concentrations.

• May cause skin sensitization in susceptible individuals; perform a patch test before topical use.

• Flammable liquid; keep away from sources of ignition and oxidizers.

• Avoid prolonged inhalation of vapors; use in well‑ventilated areas.

• Store in a cool, dry place, away from direct sunlight and heat.

• Use appropriate personal protective equipment (gloves, safety goggles) when handling.

• Shelf life: typically 24 months under recommended storage conditions.

Quality Assurance
Each batch is tested for purity (by GC), optical rotation, and density to ensure consistent quality and compliance with cosmetic and industrial standards.