What Happens When Paraffin Is Heated?

Paraffin is a white or colorless soft solid form of hydrocarbon that is derived from petroleum, coal, or oil shale. It is commonly used to make candles, wax paper, lubricants, and sealants. The name “paraffin” comes from the Latin “parum affinis” meaning “lacking affinity”, referring to paraffin’s unreactive nature.

Chemically, paraffin consists of saturated hydrocarbons, which means it contains only hydrogen and carbon atoms bonded together. It has the chemical formula CnH2n+2. The hydrocarbons in paraffin can range from methane (CH4) to very large molecules containing over 40 carbon atoms.

Some of the most common uses of paraffin wax include candles, cosmetics, polishes, art materials like crayons, and waterproofing agents for cardboard and paper. It is inexpensive and easy to work with, making it an ideal material for many household products and crafts.

Melting Point of Paraffin

Paraffin wax is characterized by having a relatively low melting point range compared to other waxes. The melting point of paraffin waxes ranges between approximately 46–68°C (115–154°F). This allows paraffin wax to transition from a solid to a liquid state at warm temperatures.

The exact melting point of a paraffin wax depends on several factors:

• Chain length – Longer hydrocarbon chains result in higher melting points. Paraffin waxes with longer carbon chains will have higher melting points.
• Purity – More purified paraffin waxes tend to have higher melting points compared to crude paraffin waxes.
• Additives – Additives mixed into paraffin wax, such as oil or resin, can lower the melting point slightly.
• Crystallization – Faster cooling and crystallization during production leads to higher melting points.

Understanding the melting behavior of paraffin wax is important for applications in candlemaking, 3D printing, and for handling and storage of the wax.

Physical Changes When Heating Paraffin

When paraffin wax is heated, some key physical changes occur. The most noticeable is that the wax transitions from a solid to a liquid state. At room temperature, paraffin wax is a brittle, opaque solid. Once heated above its melting point, paraffin liquefies into a smooth, flowing liquid. This liquefaction allows the wax to be poured into molds or containers.

In addition to changing from solid to liquid, heated paraffin wax also expands in volume and becomes less viscous. As a solid, paraffin wax is quite dense and compact. When heated into a liquid, the wax molecules spread out, increasing the volume slightly. This expansion allows the liquid wax to fill molds fully and evenly.

The viscosity or thickness of paraffin also changes dramatically when going from solid to liquid. Solid paraffin wax is stiff and brittle with very high viscosity. However, liquid paraffin wax has a much lower viscosity, allowing it to pour and spread readily. The viscosity decreases exponentially as temperature rises above the melting point.

Lastly, the color of paraffin wax can change subtly when heated. Cool paraffin is opaque and whitish. Warm, liquid wax often takes on a transparent, golden tone as impurities dissolve. The color change is reversible once the wax cools and solidifies again.

Chemical Changes in Heated Paraffin

When paraffin wax is heated to high temperatures, it can undergo chemical changes in addition to physical changes. The hydrocarbon compounds in paraffin wax can react with oxygen and undergo oxidation reactions. This leads to the formation of aldehydes, ketones, carboxylic acids and other oxygenated compounds.

At high temperatures, the hydrocarbon chains in paraffin can also link together in polymerization reactions, forming larger hydrocarbon polymers. The double bonds between carbon atoms allow different chains to join together.

Isomerization is another possible chemical change in heated paraffin wax. This involves the hydrocarbons converting from one isomer form to another. For example, n-paraffins can convert to iso-paraffins upon heating. The hydrocarbon chains are rearranged but remain the same overall chemical composition.

These chemical changes in paraffin wax at high temperatures lead to alterations in the physical properties. The melting point, color, hardness and viscosity of paraffin can change as oxidation, polymerization and isomerization reactions occur during heating. Monitoring temperature and avoiding overheating paraffin can minimize chemical changes.

Using Paraffin Wax Melts

Paraffin wax has many practical applications, especially when melted into a liquid state. One of the most common uses of melted paraffin wax is in candlemaking. The wax is melted and mixed with fragrance oils and dyes to create candles in various shapes and sizes. The melted wax cools into a solid form around the candle wick, creating a fuel source that burns slowly and evenly. Paraffin’s high melting point makes it ideal for retaining its shape in candle form. Candlemakers can safely melt paraffin on stoves or in wax melting pots to customize candle features like color, scent, and design.

In addition to candles, melted paraffin wax is useful as a lubricant and waterproofer. The liquid wax can be applied to various materials to reduce friction and wear. This allows smooth operation of mechanical parts and tools like locks, hinges, and sewing machines. Paraffin’s hydrophobic properties also make it effective for waterproofing fabrics and papers. The wax fills in pores and repels moisture, protecting items from water damage. These versatile uses take advantage of paraffin’s ability to penetrate materials in a hot liquid state, then adhere and seal them in a cooled solid form.

Heating and melting paraffin wax enables creative applications in crafts, household items, and industrial processes. Its natural properties transform through temperature changes to suit many practical purposes. With proper precautions for safe handling, melted paraffin can lend its unique benefits to candlemaking, lubrication, waterproofing, and more.

Safe Heating of Paraffin

When heating paraffin wax, it’s important to take proper safety precautions to avoid potential hazards like fumes, splattering, and fires. Here are some tips for safe paraffin heating:

Use the proper equipment – Use a double boiler, slow cooker, or wax melter designed for melting paraffin. Avoid direct stovetop heating. Electric melters with auto temperature controls are safest.

Ensure adequate ventilation – Heat paraffin in a well-ventilated area, away from smoke detectors. Open windows and use fans to avoid buildup of fumes. Never leave heating paraffin unattended.

Control the temperature – Heat paraffin slowly and evenly to the proper melting point. Don’t allow the wax to get so hot that it starts smoking. Use a thermometer and adjust heat as needed. Turn off heat once fully melted.

By taking the right precautions with equipment, ventilation, and temperature control, paraffin can be safely melted for crafts, candles, and other applications. Proper care will help avoid safety hazards when heating this commonplace wax.

Recycling and Reusing Paraffin

Paraffin wax can be recycled and reused in several ways, helping reduce waste and save money. Here are some tips for repurposing paraffin wax:

Make New Candles – Leftover candle wax can be melted down and used to make new candles. Simply shred old candle remnants into a heat safe container, melt over low heat, and pour into candle jars or molds to create new candles.

Wax Melts – Small pieces of leftover wax can be melted in a wax warmer to release fragrance. Add essential oils or fragrance if desired before melting old wax chunks to make wax melts.

Fire Starters – Allow wax to fully coat dried out cardboard egg cartons or toilet paper rolls. These wax-coated items work perfectly as fire starters for fireplaces or campfires when you need help getting a fire going.

Polishing Agent – Spread a thin layer of melted wax onto wood furniture or surfaces and buff to a shine. The wax fills in cracks and imperfections for a polished finish.

Lubricate Tools – Melted paraffin wax can be applied to help lubricate screws, hinges, drawers and other household items that have become stuck or squeaky.

By repurposing paraffin wax in creative ways, you can give new life to old candle remnants and reduce waste. Reusing paraffin is an eco-friendly, frugal option for any household.

Environmental Impact

One of the main concerns with paraffin is its effect on the environment, specifically its biodegradability and potential for pollution from spills. Since paraffin is derived from petroleum, it does not readily break down in nature. Solid paraffin wax can persist in the environment for years. Liquid paraffin spills into bodies of water are especially problematic, as the oil coats wildlife and plants, disrupting ecosystems. Clean-up of paraffin spills is difficult and costly.

There are also air pollution concerns with paraffin. When burned, paraffin releases carbon dioxide into the atmosphere. This greenhouse gas contributes to climate change. Proper ventilation is required when melting or burning paraffin to minimize indoor air pollution. The environmental effects of paraffin must be carefully managed from production to disposal. Using bio-based or renewable waxes is one way to reduce the ecological impact. Overall, the non-biodegradable nature and pollution risks of crude oil-derived paraffin make it problematic from a green perspective.

History of Paraffin

The early history of paraffin is linked to crude oil. While crude oil has been used since ancient times, it wasn’t until the 1830s that scientists started studying its chemical composition in more detail. In 1830, German chemist Karl von Reichenbach isolated an oily substance from wood tar that was similar to kerosene, which he named “paraffin.”

Over the next few decades, other scientists identified paraffin wax in coal and shale oil. Scottish chemist James Young took advantage of this discovery commercially, patenting a process to extract paraffin from coal and shale in 1850. Paraffin was originally used to waterproof boxes and smear on the bottom of beer glasses as a sealant.

However, paraffin found its first major commercial application in 1856 as a candle-making material. Paraffin candles were a marked improvement over tallow candles, burning longer and brighter. Paraffin wax was so ideal for candle making that it quickly replaced tallow as the primary candle material in Europe and North America.

Besides candles, early uses of paraffin included preservatives for fruits and rubber, chewing gum, and as a lubricant for bicycles and sewing machines. It became an important material supporting industrialization and commercial development in the late 19th century.

Future Applications

Paraffin wax has been an incredibly useful material for over a century, but researchers continue to find new and innovative applications for it. Here are some emerging uses and technologies that take advantage of paraffin’s unique properties:

3D printing – Paraffin’s thermoplasticity makes it an ideal material for 3D printing. Printers can precisely deposit layers of melted paraffin to create complex shapes and structures. 3D printed paraffin shows promise in medical applications like customized implants and prosthetics.

Drug delivery – Scientists are developing paraffin-based nanoparticles to deliver drugs and therapies. The nanoparticles can be injected and safely travel through the body to target specific areas like tumors. Controlled drug release from the paraffin particles improves treatment effectiveness.

Phase change materials – Paraffin’s ability to absorb and release large amounts of heat as it melts and solidifies makes it an effective phase change material. Paraffin PCMs are being integrated into solar power plants, spacecraft, electronics, and buildings to provide thermal regulation.

Oil and gas – Paraffin waxes help optimize oil and gas pipeline flows. New high-tech paraffins are being synthesized to handle extreme temperature and pressure environments in deep sea drilling and remote oil fields.

With researchers continually finding new ways to exploit its unique physical and chemical properties, paraffin wax will remain an extraordinarily versatile material well into the future.