What Are The Components Of Paraffin?
What is Paraffin?
Paraffin is a soft, colorless, or white waxy solid derived from petroleum, coal, or oil shale that consists of a mixture of hydrocarbon molecules containing between 20 and 40 carbon atoms (“Paraffin wax,” n.d.). It is also known as paraffin wax or petroleum wax.
Paraffin wax is extracted during the refining process of crude oil. It is the residue left after the separation of gasoline, naphtha, kerosene and diesel oil. The raw paraffin wax extracted often varies in color from light yellow to black based on the source of the crude oil (“Paraffin wax,” 2022).
Paraffin has a wide variety of uses. It is commonly used to make candles, as a lubricant, electrical insulator, waterproofing agent, and in cosmetic products. In medicine, paraffin is used in heat therapies to help alleviate pain and increase mobility in hands and feet. It is also used in anti-rust coatings, polishes, art materials, and board sizing for paper and textiles (Healthline, n.d.).
Chemical Composition
Paraffin wax is made up of hydrocarbons, which are molecules that contain only hydrogen and carbon atoms. The hydrocarbons in paraffin wax are a specific type called alkanes that have the general chemical formula CnH2n+2 (source: Paraffin wax – Wikipedia).
There are different types of paraffin waxes based on the carbon chain length of the alkanes present. Shorter chain alkanes like methane (C1), ethane (C2), propane (C3), and butane (C4) are gaseous at room temperature. Longer chain alkanes from C5 to C18 are liquids, while very long chains above C18 are solids at room temperature that make up paraffin wax (source: Paraffin hydrocarbon | Petroleum, Alkanes & Alkenes – Britannica).
Alkanes
Paraffin contains alkanes, which are saturated hydrocarbons containing only carbon and hydrogen atoms connected by single bonds. Alkanes are also known as paraffins.
The alkanes in paraffin are primarily straight chain alkanes, where the carbon atoms form a linear chain structure. Some of the common straight chain alkanes found in paraffin include methane (CH4), ethane (C2H6), propane (C3H8), and butane (C4H10).
Alkanes are relatively unreactive compared to other organic compounds due to the stable, saturated carbon-carbon and carbon-hydrogen bonds. They are non-polar molecules and insoluble in water. Alkanes are colorless and odorless liquids or gases at room temperature and pressure. The boiling point of alkanes increases as the molecular size increases. Some properties of alkanes include:
- Low reactivity
- Non-polar
- Insoluble in water
- Gaseous or liquid state at room temperature
- Increase in boiling point with molecular size
The chemistry of alkanes provides the foundation for paraffin’s properties and applications.
Common Alkanes in Paraffin
Some of the most common alkanes found in paraffin include:
Methane
Methane (CH4) is the simplest alkane, consisting of one carbon atom and four hydrogen atoms. It is a major component of natural gas and is highly flammable. Methane is used as a fuel and in the production of hydrogen, methanol, and carbon black (Britannica).
Ethane
Ethane (C2H6) contains two carbon atoms and six hydrogen atoms. It is normally a gas at room temperature. Ethane is used in the petrochemical industry to produce ethylene, which is used to make plastics and other polymers (ScienceDirect).
Propane
Propane (C3H8) has three carbon atoms and eight hydrogen atoms. It is commonly used as a fuel for heating, cooking, and vehicles. Propane is also used as a refrigerant, aerosol propellant, and petrochemical feedstock (Wikipedia).
Butane
Butane (C4H10) contains four carbon atoms and ten hydrogen atoms. At room temperature it is a highly flammable gas. Butane is used as a fuel, refrigerant, and feedstock for producing plastics and synthetic rubber (Britannica).
Pentane
Pentane (C5H12) has five carbon atoms and twelve hydrogen atoms. It is a liquid at room temperature. Pentane is used as a blowing agent in foam production and as a solvent in adhesives and chemical manufacturing (ScienceDirect).
Cycloalkanes
Cycloalkanes are saturated hydrocarbons containing one or more carbon rings. They are a component of paraffin wax. Some common cycloalkanes found in paraffin include:
Cyclopentane (C5H10)
Cyclohexane (C6H12)
Methylcyclopentane (C6H12)
Cycloalkanes have unique chemical properties compared to straight-chain alkanes. They exhibit angle strain and torsional strain due to the rigidity of their carbon rings. This causes them to be less stable and more reactive than their acyclic counterparts. Cycloalkanes cannot rotate freely around carbon-carbon bonds, which restricts conformations and increases strain energy. The bond angles are compressed to 109.5° to achieve tetrahedral geometry. Cyclohexane has the most stable ring structure, while smaller rings like cyclopropane and cyclobutane have substantial angle strain. Larger rings also have higher strain energy.
The special structure of cycloalkanes gives them different physical properties like boiling point, density, and viscosity compared to acyclic alkanes. Cycloalkanes tend to have higher melting and boiling points for their molecular weight. Their ring structure reduces volatility. Cycloalkanes are also less dense than straight-chain alkanes due to the twisted shape preventing tight packing of molecules.
Overall, the cyclic structure of cycloalkanes produces unique chemical and physical properties important for their role in paraffin.
Common Cycloalkanes
Cycloalkanes, also known as naphthenes, are cyclic saturated hydrocarbons consisting of carbon atoms joined in rings. The most abundant cycloalkanes found in paraffin wax are cyclopropane, cyclobutane, and cyclopentane:
Cyclopropane is the cycloalkane with the formula (CH2)3. It is the smallest cycloalkane. According to the Penn State University online petroleum course, cyclopropane is rarely found in crude oil in concentrations above 0.1%.
Cyclobutane has the formula (CH2)4 and is a highly strained and unstable cycloalkane. It is rarely found in crude oil or natural gas. According to a ScienceDirect overview, cyclobutane accounts for less than 0.1% of most crude oils.
Cyclopentane is a cycloalkane with the formula (CH2)5. It is much more stable than cyclobutane. According to the ScienceDirect engineering overview, cyclopentane is often a predominant cycloalkane in crude oil along with methylcyclopentane.
Manufacturing
Paraffin wax is manufactured from petroleum feedstocks during the refining process. Crude oil is distilled into various fractions or cuts, including gasoline, kerosene, diesel fuel, lubricating oils, and waxes.1 The wax cut contains paraffin waxes along with other hydrocarbons. To isolate the paraffin wax, the wax cut undergoes additional processing called dewaxing.
Dewaxing exploits the fact that paraffin waxes have higher melting points than other hydrocarbons in the wax cut. The mixture is chilled to form crystals which are then separated from the liquid by filtration. The resulting solid is the crude paraffin wax.2
Further refining and distillation produces paraffin waxes of different grades. The melting point of the wax increases with the length of the hydrocarbon chains. Higher grades have longer chains and melt at higher temperatures. Grades are categorized into fully refined, semi-refined, and scale wax.
Uses
Paraffin wax has many common uses including:
Candles
Paraffin wax is one of the most common waxes used to make candles. It burns cleanly and consistently, making it ideal for candlemaking. Most store-bought candles today are made from paraffin wax. The wax allows candles to burn slowly and provides the fuel for the flame. Paraffin’s high melting point makes it retain its shape as a solid when not lit.[1]
Cosmetics
Paraffin wax is used in some cosmetics to help protect and moisturize skin. It can be found in lip balms, hand creams, and moisturizers. The emollient properties of paraffin help trap moisture in the skin while also forming a protective barrier. This can help prevent dryness and cracking of the skin. Paraffin wax is also sometimes used in skin and beauty treatments like facials and pedicures.[2]
Food Processing
Food grade paraffin wax is used as a sealant in food packaging and processing. Because it is inert and resistant to moisture, paraffin can help protect food items from oxygen, water loss, and contamination. Common applications include sealants for jars, lids, and cartons. Paraffin coating on fruits and vegetables can also help extend their shelf life. The wax provides a protective barrier that slows down spoilage.[3]
Health and Safety
Paraffin wax has relatively low toxicity but some precautions should still be taken when using it.
If ingested, paraffin wax can cause intestinal obstruction. Children have been known to eat paraffin wax, so it’s important to keep products containing it safely stored away from kids. There have also been rare cases of people intentionally ingesting paraffin wax to attempt suicide or self-harm (1).
Environmental concerns with paraffin wax center around its persistence in the environment and its origins from petroleum. Paraffin wax is non-biodegradable and can accumulate in the environment when released. This is of particular concern in aquatic environments. The other main concern is that paraffin wax is derived from crude oil, a nonrenewable resource. However, paraffin wax can be produced from natural gas as well (2).
Overall, paraffin wax has low toxicity for humans but some care should be taken when ingestion is possible. Environmental impacts can be minimized by proper disposal and increasing use of renewable feedstocks.
Future of Paraffin
The future of paraffin looks promising as manufacturers continue to innovate production methods and scientists discover new applications for this versatile material. According to one industry report, the global paraffin wax market is expected to expand at a CAGR of 3.91% from 2022-2030, reaching a value of $8.6 billion by 2030.
One key development is improvements in manufacturing techniques that make paraffin production more efficient and environmentally friendly. New catalytic cracking methods are being used to boost yields while reducing unwanted byproducts. Manufacturers are also exploring renewable feedstocks like soybean oil as an alternative to crude oil.
In terms of applications, researchers are studying the use of paraffin wax in 3D printing, flexible electronics, and biomedical devices. The flexibility and non-toxicity of paraffin make it well-suited for these high-tech uses. Paraffin’s moisture resistance also enables applications in sustainable building materials.
While paraffin remains indispensable for many industries, alternatives are emerging for certain applications. For example, beeswax and soy wax can substitute paraffin in candles. Synthetic waxes like polyethylene offer functionality similar to paraffin. Ultimately though, paraffin’s versatility and cost-effectiveness will ensure it continues to thrive.
