Description

Slack wax is a petroleum wax that retains a variable amount of oil. It is commonly recovered during the dewaxing of lubricating-oil streams. Unlike fully refined paraffin wax, slack wax is an intermediate or industrial-grade material whose oil content, melting behavior, and color depend on its source and processing.

 

How is slack wax produced?

Suitable refinery fractions are processed to make lubricating base stocks. In solvent dewaxing, wax-containing molecules are crystallized and separated from the oil to improve the oil’s low-temperature properties. The recovered wax-and-oil material is slack wax. Further deoiling and finishing can turn suitable slack wax into more refined wax grades.

Slack wax is not automatically fully refined paraffin wax. The two have different oil-content and purity requirements. Suitability for candles, coatings, or another end use depends on the specific grade and the customer’s formulation.

 

What is slack wax used for?

Depending on the grade and oil content, slack wax may be used as:

• Feedstock for semi-refined or fully refined paraffin wax
• An ingredient in selected candle and wax-blend formulations
• A component in board sizing, wax emulsions and suitable industrial treatments

Applications differ by oil content, melting range, and color. A grade intended for further refining should not be represented as food-contact, cosmetic, or pharmaceutical grade without the required purification and documented compliance.

 

Key properties to check

• Oil content
• Melting or congealing point
• Color
• Penetration or hardness, where relevant
• Viscosity when molten, and water content

Review the agreed specification and a recent Certificate of Analysis for each shipment.

 

Availability & specification

Product availability and the specification of a particular slack wax grade vary by supplier. Contact our team for the grade, oil content, agreed specification, Certificate of Analysis, current pricing and packaging options.

Technical references: ExxonMobil — “Wax Application, Product & Operation FAQ” and “Slack Paraffin Wax”; Shell — “Slack Wax Product Stewardship Summary”.