Slack wax

What Is Slack Wax?

Slack wax is a semi-refined petroleum product derived from the de-waxing process of lubricating oil base stocks. It is a mixture of oil and wax, typically containing 5% to 30% oil, depending on its grade. Slack wax is produced during the early stages of wax refining and serves as a feedstock for further processing into fully refined paraffin wax, microcrystalline wax, and other specialty waxes.

Slack wax appears as a soft, pale yellow to brown solid and has a greasy texture due to its relatively high oil content.

Main Grades of Slack Wax

Slack wax is typically categorized based on its oil content and melting point:

  1. Light Slack Wax

    • Oil content: 10–30%

    • Melting point: ~50–60°C

    • Softer and more oily; used in rubber and particleboard industries

  2. Heavy Slack Wax

    • Oil content: 5–15%

    • Melting point: ~60–70°C

    • More solid and waxy; used in candle production and paraffin refining

Exact specifications may vary by refinery and intended application.

Key Applications of Slack Wax

Slack wax is used in a wide range of industries either as a raw material or in its semi-refined form, including:

  • 🕯 Candle Making: Especially for rustic or industrial-grade candles

  • 🏗 Particleboard & MDF Production: As a water-repellent additive

  • 🛢 Rubber & Tire Industry: Improves processability and protects against ozone

  • 📦 Packaging & Corrugated Board: Used in wax coatings for moisture resistance

  • 🏠 Polishes & Surface Treatments: Ingredient in floor, furniture, and shoe polish

  • 🧼 Match Industry: Used in match heads and coatings

  • 🏭 Feedstock: For producing fully refined paraffin and specialty waxes

Typical Properties of Slack Wax

Property Range (Typical)
Oil Content 5% – 30%
Melting Point 50°C – 70°C
Color Pale yellow to brown
Form Solid, waxy flakes or slabs
Odor Mild petroleum smell

Packaging and Handling

  • Available in slabs, flakes, or drums (usually 180–200 kg)

  • Should be stored in cool, dry places, away from direct sunlight

  • Melting should be done in controlled, ventilated environments

Conclusion

Slack wax is a versatile and essential byproduct of the oil refining process, offering value across multiple downstream industries. Whether used directly or further processed, its balance of oil and wax content makes it an important commodity in industrial, manufacturing, and commercial applications worldwide.