7 minute read
Refining beeswax and its commercial uses
Stephen Case-Green, Technical Director, the British Wax Refining Company Ltd, UK
The British Wax Refining Company has been refining and supplying beeswax for over 100 years. Started in Surrey, UK in 1914 by my great grandfather, the Company has undergone many changes over the years, however our beeswax processing has changed little and remains a significant part of our business. Newer materials have become available and sometimes replaced beeswax, yet there are many applications where beeswax is irreplaceable and now, when people are increasingly concerned about the sustainability of products, it certainly has a part to play.
Refining beeswax
A lot of beeswax is required: a usual batch size is 800-1,000kg. We import most of our beeswax and source enough crude beeswax to fill a shipping container: 14–20 tonnes. We purchase crude beeswax mainly from Africa and have set up a new Joint Venture Company in Kenya to refine beeswax produced in Kenya and other East African countries. To gather enough beeswax, a network has been established that collects it from farmers and producer groups. When enough beeswax has been collected, lorries take it to a facility in Kenya for processing. We recently started a programme of sourcing pesticide free/organic beeswax using the same type of network of collectors. This has involved providing training to ensure bees are treated well, the beeswax is free of any pesticides such as pyrethroids found in mosquito repellent, paying good prices for high quality beeswax and providing access to beekeeping resources. Since 2011 all beeswax entering the EU has had to undergo a rendering process. The beeswax is melted and left at high temperature for a time. Leaving beeswax at an elevated temperature is not ideal for producing the lightest beeswax colour but it is necessary to stop the possible transmission of organisms that may cause problems to bees. Beeswax refining is more a case of cleaning it and changing the colour than removing any of the many
compounds of which the beeswax consists. The amount of refining carried out will depend on the quality of the beeswax and the end use.
Step 1
This process removes any water-soluble materials and heavy solids. The beeswax is melted over water and allowed to settle. Water soluble materials will dissolve in the water layer and solids will fall to the bottom of the vessel. Liquid beeswax is then taken off the top and solidified. As this is done when the beeswax is rendered, we have less need to do it, as the received beeswax is already washed.
Step 2
This process removes fine solids and helps improve the colour. Liquid beeswax is mixed with fuller’s earth and activated carbon, which have two functions: they absorb some of the molecules that colour the beeswax and act as a filter medium. After allowing time to react, the fuller’s earth and carbon are removed by pumping the beeswax through a filter press. This is a series of chambers surrounded by a cloth membrane. They allow the liquid beeswax to pass through the cloth, but not the fuller’s earth and carbon, which also act as filter media for very fine particles as they are deposited on the cloth. The beeswax produced at this stage is of refined yellow standard and is usable in many applications. If a whiter product is required, further bleaching can be carried out, which is done using peroxides. Up to the early 20th century, the principal means of bleaching beeswax was the sun. At the facility in Kenya we are looking at ways to re-introduce this method, so that we can once again produce completely chemical free certified organic sun-bleached beeswax. Once at the standard required, the beeswax can be solidified and testing is carried out to confirm its purity.
Good properties
Before we look at some uses of beeswax, here are its useful properties: • Low melting point • Combustible • Insoluble in water • Compatible with oils, fats and resins • Inert • Non-toxic • Plasticiser • Translucent As a chemist, for many years when compiling this list, I concentrated on the chemical and physical properties of the beeswax. However, two characteristics are increasingly important to consumers: that beeswax is a natural product and sustainable. A few applications use pure beeswax, but most are in combination with other materials. We have many years’ experience in formulating beeswax blends and the materials used depend on several factors. While
some materials have been commercially available only since the last century, beeswax has been used in applications for thousands of years and for most of that time was the only material of its type. Consequently, there are many uses that have been around for a long time, many of which will be familiar. As more types of beeswax have become available, some of the uses have been replaced with alternatives, often due to price. For example, we rarely come across the use of beeswax in applications such as lost-wax casting or in explosives, which were important uses in the past.
Uses of beeswax
The first is the production of foundation sheets for use by beekeepers with frame hives.
Candle making
A main use of beeswax is in candle making. We can all appreciate the comforting yellow glow from a pure beeswax candle. However, the trend over the last twenty years away from pillar candles and towards highly scented container candles has led to a greater use of hydrogenated oils such as coconut, rapeseed and soy, with beeswax used as a component to give a higher melting point and smoother surface.
Cosmetics
Another major application is in cosmetics where beeswax is used in barrier creams, cold creams, hair waxes, moisturisers, pomades and putties. For our own production of depilatory waxes, we have found beeswax to be superior to other waxes such as microcrystalline, for plasticising the resins that make up the bulk of the blend. While many of our depilatory wax blends contain mixtures of beeswax, colours, fragrances, polymers and resins, the simplest contains a mixture of beeswax and rosin, a simple formula from two natural, sustainable materials. In most cosmetic products, beeswax is a minor component but for moustache wax, it is the major ingredient, allowing the hair to be stiffened and shaped.
Food production
As beeswax is non-toxic it can be used in food contact applications and has an E number of 901. Examples of use include baking where it is used as a release agent, preventing sticking during baking. For confectionery, a barrier layer can be made on the surface of hard gums and sweets, mostly in combination with other materials such as carnauba wax. This acts to prevent the sweets losing water and gives them a glossy, nonstick coating. The waxes are applied by tumbling the confectionery in a rotating drum which has had wax melted on to the side. Layers of wax are built up as the confectionery tumbles around. With the current interest in reducing the use of plastics, reusable wrappings based on beeswax are being produced as alternatives to cling film. These are blends of beeswax, oils and resins that can be reused and are very environmentally friendly. I have heard beeswax called ‘nature’s first plastic’ and these sorts of products are a good example of why.
Animal feeds
The non-toxic/inertness of beeswax is used in mineral supplements for cows and sheep. Many diets of these animals do not contain enough trace elements such as cobalt, iodine and selenium, resulting in ill health, low fertility, poor growth and reduced milk yields. The beeswax forms part of a bolus given to the cows and sheep which slowly releases in the animal’s stomach (reticulorumen). The slow release allows the elements to be absorbed at a constant rate.
Figure casting
One of the most well-known uses of beeswax is in figure casting, particularly those produced by Madame Tussauds museums. Beeswax makes up most of the wax blend used in these figures and being translucent gives the figures a more natural fleshlike quality. The first step involves the sculpting of a clay model, from which a mould is made. Casting of the head uses the slush casting technique. Liquid beeswax is added to the mould and allowed to cool. When an appropriate thickness of solidified beeswax has been built up, excess beeswax is poured out to give a hollow head. This technique helps to minimise shrinkage as the beeswax contracts and gives a lighter casting which is easier to support when on display. To give as lifelike appearance as possible, hairs are attached to the head by softening small areas and inserting them into the beeswax.
Other uses
Artists and designers use beeswax in batik and encaustic painting. Beeswax is used in a variety of applications as a lubricant. Most are blends of beeswax with fats and oils. In the manufacture of sporting ammunition,