A Brief Introduction To Candle

Before the invention of electric lighting, candles and oil lamps were commonly used for illumination. Candles are still used routinely nowadays especially in areas without electricity.

In the developed world today, candles are used mainly for their aesthetic value and scent, particularly to set a soft, warm, or romantic atmosphere, for emergency lighting during electrical power failures, and for religious or ritual purposes. Scented candles are used in aromatherapy.

Candles are made up of two components – wax and a wick.

The wax may be supplemented with additives such as:

                             

                Colorant which gives an attractive appearance to candle                        different kinds of fragrances to make scented candles

           “metallic” surfaces which are not metal but an organic material.

How candle burns????? 

·         Acting like a fuel pump, the wick draws the liquefied wax up into the flame to burn by capillary action. When the liquid fuel, typically melted candle wax, reaches the flame it then vaporizes and combusts.

·         The candle wick influences size of the flame and corresponding rate of burning.

·         Different wick sizes allow for different amounts of fuel to be drawn into the flame. Too much fuel and the flame will flare and soot; too little fuel and the flame will sputter out.

~~~The Wax~~~

The structural formula of wax

Definition:

Any of various natural, oily or greasy heat-sensitive substances, consisting of hydrocarbons or esters of fatty acids that are insoluble in water but soluble in nonpolar organic solvents such as ether and benzene.

Candle Wax Facts

Regardless of whether the origin of the candle wax is petroleum, rock layers, animal or vegetable, all candle waxes are primarily hydrocarbons, they share several common characteristics.

•          Basically hydrocarbons have similar chemical compositions 
•          Solid at room temperature and liquid when heated, known as thermo plasticity
•          Low reactivity
•          Insoluble in water
•          Low toxicity; low odor
•          Smooth texture; buffable under slight pressure

Waxes burn with a yellow flame due to the presence of carbon. There is no such thing as a soot-free wax. All organic compounds when burned will emit some carbon (soot) due to incomplete combustion. Sooting is primarily a factor of wick length and flame disturbance.

A wax has to be malleable solid at room temperature and have an adequate high melting point approximately above 45°C so that the candle does not bend when exposed to sunlight and with low viscosity when melted. As the candles typically burn indoors it is also important that the wax does not contain too many chemical impurities which may cause pollution problems (e.g. soot) when burning the candles.

Wax has to have a melting point above 40ºC. At 40ºC it must melt without decomposing, and its surface shall be soft and workable. Wax normally melts between 50 to 90ºC. . 

Development of Candle Waxes

Country & Time	Type of wax developed and used
Ancient Egyptians and the Early Romans	Tallow (a by-product of beef-fat rendering)
Tang Dynasty (618-907 A.D.)	Beeswax  (a by-product of honey collection, rarely used in  Europe in the Middle Ages’  homes because of its great  expense)
China (12th century)	Wax derived from Coccos pella  insect
Early Japan	Wax derived from tree nuts
India	Wax derived from the fruit of cinnamon tree
Europe and the Americas (18th century)	Spermaceti wax   (clean-burning, low-odor wax extracted from the head    of a Sperm Whale)    (76% wax esters;  23% triacylglycerols)
Europe (mid-1800s)	Stearin wax   (initially extracting stearic acid from animal fatty  acids, now produced almost exclusively from palm waxes)   Paraffin wax     (a product of petroleum refining)
Latter half of the 20th century	Synthetic and chemically synthesized waxes, for    example: -- gels (a mixture of polymer and mineral oil) -- microcrystalline wax
Late 1990s	-- Soy wax   -- Palm wax

The composition of the animal fatty acids:

Saturated Fatty acids	Monounsaturated Fatty acids	Polyunsaturated Fatty acids
Palmitic acid: 26%	Oleic acid: 47%	Linoleic acid: 3%
*Stearic acid: 14%	Palmitoleic acid: 3%	Linolenic acid: 1%
Myristic acid: 3%

*Stearic acid, CH₃(CH₂)₁₆CO₂H, is typically used, at levels up to 5%. The purpose is to harden the wax and to improve the appearance of the candle.

This table showed the types of wax that used in the market.

From the table above, we can see that paraffin wax and beeswax is the types of wax used more commonly in the candlemaking. Therefore, we will discuss more on this two types of wax.

Paraffin Wax

Paraffin wax is a common name for a group of high molecular weight alkane hydrocarbons with the general formula C_nH_2n+2 where n is greater than about 20. It is mostly found as a white, odorless, tasteless solid with a typical melting point between about 47°C and 65°C. Paraffin wax is typically macrocrystalline and brittle. Paraffin waxes are generally unaffected by most ordinary chemicals and burns readily.

Paraffin wax is a petrolatum wax. When Petroleum companies "yield" the crude oil and process it, they refine the oil, separating the different properties into Gasoline, Kerosene, Lubrication oil, and many other products. In many cases, the wax in the petroleum is considered undesirable and is refined out. The refinery will process the wax into a clean, clear liquid, or as a solid milky white block, and make it available to companies who may have a use for it. The

refined wax is called 

paraffin, which comes from the Latin "parum = few or without" and "affinis = connection or attraction (affinity)". Basically there are few substances that will chemically react with or bind to this type of wax.

There are many arguments about paraffin wax:

Many websites had said that paraffin wax is inorganic and harmful candle wax as it emits 11 known toxins while burning, including toluene, benzene, and formaldehyde, which are known carcinogens. Have you ever noticed black soot around the edge of your candle glass, or on the walls or ceilings in your home? Well, that soot contains some of the same toxins found in diesel fuel. So, there is no wonder it leaves a residue on walls, ceilings, fabrics, and ventilation systems, and the scariest fact is that you and your family are breathing it into your lungs! 

However in some website, paraffin wax is consider as organic substance due to it is ultimately come from plant life. In order to protect themselves from adverse weather conditions, plants produce a layer of wax on their leaves and stems. Deposition of material from dead plants 100-700 million years ago in large quantities and eventually became buried beneath the surface of the earth and turned the slowly decaying plant material into crude oil (petroleum). Because of the nature of waxes, being inert and water repellent, they were unaffected by the decomposition of the plant material and remained intact, suspended within the crude oil.

Beeswax

A less common but more highly renowned wax for candlemaking is beeswax. Prior to the 19th century, a "wax" candle typically referred to a beeswax candle. In order to be "organic", there must be hydrogen-carbon bonds. Because of plenty of hydrogen-carbon bonds in bee's wax, so it is an organic compound.

The characteristics:

-Chemical formula:
 C₁₅ H₃₁ CO₂ C₃₀ H₆₁

-Insoluble in water, density 0.95

-Becomes brittle below 18 °C

-Becomes soft and pliable above 35 to 40°C. 

-Melting point is 62-65 °C. (highest melting point of any known wax) 

-Does not deteriorate over time (usable wax found in ancient tombs

It is classified as a natural wax as it is produced by the honeybee for use in the manufacture of honeycombs. A major component of beeswax is the ester myricyl palmitate which is used in constructing their honeycombs. As is the case with paraffin, beeswax is collecting as a by-product. The capping wax must be removed in order to extract the honey.

Because beeswax is harvested in very small quantities therefore it is more expensive than paraffin. It is used extensively in cosmetics and candlemaking. Candles made from 100% beeswax are generally held in high regard, when burning they glow beautifully and impart a very pleasant honey like aroma.

Beeswax is a tough wax formed from a mixture of several compounds. Its main components are palmitate, palmitoleate, and oleate esters of long-chain (30-32 carbons) aliphatic alcohols, with the ratio of triacontanyl palmitate CH₃(CH₂)₂₉O-CO-(CH₂)₁₄CH₃ to cerotic acid, CH₃(CH₂)₂₄COOH, the two principal components, being 6:1.

Wax Content Type	Percent
Hydrocarbons	14%
Monoesters	35%
Diesters	14%
Triesters	3%
Hydroxy monoesters	4%
Hydroxy polyesters	8%
Acid esters	1%
Acid polyesters	2%
Free acids	12%
Free alcohols	1%
Unidentified	6%

Chemical components in beeswax. 

Advantages of 100% natural beeswax fuel:

1) Burn brighter, longer, and cleaner than any other candle!

2) The flame emits essentially the same light spectrum as the sun

3) Negative ions in the process of burning emits that are known to clean the air and invigorate the body (reportedly, stimulating the puitary gland, thus increasing creativity, intuition, and dream activity).

4) Naturally scented by the honey and nectar of flowers and gives off a delicate fragrance