We are independent & ad-supported. We may earn a commission for purchases made through our links.
Advertiser Disclosure
Our website is an independent, advertising-supported platform. We provide our content free of charge to our readers, and to keep it that way, we rely on revenue generated through advertisements and affiliate partnerships. This means that when you click on certain links on our site and make a purchase, we may earn a commission. Learn more.
How We Make Money
We sustain our operations through affiliate commissions and advertising. If you click on an affiliate link and make a purchase, we may receive a commission from the merchant at no additional cost to you. We also display advertisements on our website, which help generate revenue to support our work and keep our content free for readers. Our editorial team operates independently of our advertising and affiliate partnerships to ensure that our content remains unbiased and focused on providing you with the best information and recommendations based on thorough research and honest evaluations. To remain transparent, we’ve provided a list of our current affiliate partners here.

What is Thermal Cracking?

Mary McMahon
Updated May 17, 2024
Our promise to you
About Mechanics is dedicated to creating trustworthy, high-quality content that always prioritizes transparency, integrity, and inclusivity above all else. Our ensure that our content creation and review process includes rigorous fact-checking, evidence-based, and continual updates to ensure accuracy and reliability.

Our Promise to you

Founded in 2002, our company has been a trusted resource for readers seeking informative and engaging content. Our dedication to quality remains unwavering—and will never change. We follow a strict editorial policy, ensuring that our content is authored by highly qualified professionals and edited by subject matter experts. This guarantees that everything we publish is objective, accurate, and trustworthy.

Over the years, we've refined our approach to cover a wide range of topics, providing readers with reliable and practical advice to enhance their knowledge and skills. That's why millions of readers turn to us each year. Join us in celebrating the joy of learning, guided by standards you can trust.

Editorial Standards

At About Mechanics, we are committed to creating content that you can trust. Our editorial process is designed to ensure that every piece of content we publish is accurate, reliable, and informative.

Our team of experienced writers and editors follows a strict set of guidelines to ensure the highest quality content. We conduct thorough research, fact-check all information, and rely on credible sources to back up our claims. Our content is reviewed by subject-matter experts to ensure accuracy and clarity.

We believe in transparency and maintain editorial independence from our advertisers. Our team does not receive direct compensation from advertisers, allowing us to create unbiased content that prioritizes your interests.

Thermal cracking is a process in which hydrocarbons such as crude oil are subjected to high heat and temperature to break the molecular bonds and reduce the molecular weight of the substance being cracked. This process is used to extract usable components, known as fractions, which are released during the cracking process. It is one among several cracking methods used in the petroleum industry to process crude oil and other petroleum products for commercial use.

In the thermal cracking process, the compound to be cracked is subjected to high heat and pressure. Sometimes a catalyst is added to control the chemical reactions which occur during the process, with the goal of promoting the development of specific molecules. Fractions which have a low boiling point, such as gasoline, will be released first. As the cracking proceeds, fractions of various molecular weights can be extracted and processed further for additional uses, or packaged for transport and sale.

This process creates free radicals at the sites where molecular bonds are broken, which can be harnessed in chemical reactions such as polymerization to create new chemical compounds. A wide variety of compounds are extracted or derived through these types of processes, making it a valuable part of petroleum refining. The process can be supervised by petroleum engineers or chemists who are familiar with the needs of the market, the product being worked with, and the cracking process.

Sometimes known as pyrolysis because it involves the controlled decomposition of a chemical compound under heat and pressure, thermal cracking is designed to create more useful fractions. The cracking can be adjusted to meet needs like a rise in demand for a particular product, or a shortage of a product caused by changes in refinery capacity. Thermal cracking of petroleum is also often discussed in chemistry classes while introducing students to basic chemical concepts which come up in the refinery industry.

The term thermal cracking is also used in reference to concrete, asphalt, and similar materials. In this case, low temperatures make the material prone to cracking. Things like asphalt are elastic at temperate and high temperatures, deforming as they are stressed, but when it is cold, the material may crack or fracture. Thermal cracking in concrete and similar materials is a cause for concern in very cold environments, especially when the material is being used for structures such as bridges and buildings, where failure could cause a catastrophe.

About Mechanics is dedicated to providing accurate and trustworthy information. We carefully select reputable sources and employ a rigorous fact-checking process to maintain the highest standards. To learn more about our commitment to accuracy, read our editorial process.
Mary McMahon
By Mary McMahon

Ever since she began contributing to the site several years ago, Mary has embraced the exciting challenge of being a About Mechanics researcher and writer. Mary has a liberal arts degree from Goddard College and spends her free time reading, cooking, and exploring the great outdoors.

Discussion Comments
By marieg123 — On Dec 16, 2013

I'm doing a project on cracking and I was wondering if someone could tell me the pros and cons of both catalytic and thermal cracking. I tried searching online but it didn't help much. Any help is greatly appreciated.

By BBSmith — On Jun 04, 2011

Cracking oil using catalysts not only promotes development of specific molecules, it also reduces the amount of pressure required. The catalysts are usually solids like aluminum hydrosilicate, certain clays, or bauxite, in the form of beads or powders. It does sound a bit odd to discuss "cracking" a liquid but it's really cracking the molecular bonds.

By Acolyte — On Jun 02, 2011

So thermal cracking is useful in a variety of ways and dangerous in others. We've probably all seen the bad effects of concrete cracking and worry about it on bridges.

But thermal cracking as part of the oil refining process is how we get our gasoline! More than 50% of the crude oil is converted to gas and one way of doing that is by cracking. It breaks down the molecules of the heavy oil.

Mary McMahon
Mary McMahon

Ever since she began contributing to the site several years ago, Mary has embraced the exciting challenge of being a...

Learn more
About Mechanics, in your inbox

Our latest articles, guides, and more, delivered daily.

About Mechanics, in your inbox

Our latest articles, guides, and more, delivered daily.