Not all waxes are created equal. From paraffin to beeswax (of course!), the choice of wax plays a crucial role in the candle’s aesthetics, burn time, and environmental impact. In this post, we’ll explore how four different waxes commonly used in candle making are produced.
1. Paraffin Wax
Paraffin wax is derived from petroleum, coal, or shale. It starts out as what’s called a slack wax, which is a byproduct of manufacturing lubricating oils.
One the slack wax is obtained, the oils need to be removed. This is commonly done by heating the wax, mixing it with a solvent, and allowing it to cool. On cooling, the wax and the oil are separated. This leaves a solid wax with some solvent and a liquid oil with some solvent. This is filtered to leave the wax/solvent mix.
At this stage, the wax goes through a distillation process. The distillation removes the remaining solvent using a steam-heated kettle. The result of this is a product wax ready for further refining.
The next step in the process results in a fully refined wax. To get to this state, the product wax is passed through a bed of clay, which removes colour. It is also passed through a vacuum stripping tower, which removes odours.
2. Vegetable Waxes (Soy, Palm, Coconut)
First, let’s see where each type of wax comes from:
- Soy wax – derived from the oil of soybeans. The process starts by harvesting soybeans. From there, the beans are washed, split, de-hulled, and turned into flakes. Next, the oil is removed.
- Palm wax – derived from the fruit of oil palm trees. The oil is removed from the fruit and kernel through pressing and clarified to remove impurities.
- Coconut wax – derived from the oil naturally found in coconuts. The process starts by cold pressing the oil out of the meat of coconuts
After the oil is removed, it goes through a hydrogenation process. Hydrogenation is a chemical reaction between molecular hydrogen and an element or compound usually in the presence of a catalyst. In the case of soy, molecular hydrogen, soybean oil (element or compound), and often nickel (catalyst) are present.
Once hydrogenation is complete, the characteristics of the wax have changed. The melting point is different, and it is solid at room temperature. Now, it’s ready for use in candles.
Beeswax is an insect-made wax. It is secreted from the wax glands of the honey bee.
Beeswax is one of the main building materials in the beehive. It can be harvested along with honey. Directly from the hive, beeswax may contain dirt, grass, honey, bee parts, and other contaminants.
There are two steps in the process to convert beeswax into a material suitable for candle making:
Rendering is often done using water to remove honey and separate the wax from some particles. The wax and water are heated until the wax melts. The wax is allowed to cool and removed. Heavy particles will drop to the bottom of the container and honey will dissolve in water. However, some particles will still remain in the wax.
To remove the remaining particles, the wax is re-melted and put through filters of increasingly smaller size. From there, the wax is ready to use in candles.
4. Gel Wax
Gel wax is a petroleum derived wax with a unique gel-like consistency. It is created by polymerizing mineral oil and polymer resin.
Polymerization is a chemical process where small molecules (monomers) come together to form long-chain polymers.
Once polymerization is complete, the gel wax is ready for use in candle making.
Each wax has different pros and cons. We love using beeswax because of the minimal processing to keep us that much closer to nature! What is your favourite wax and why?