Is Graphite Flammable? Does graphite explode when heated? - FlameVenge
February 2, 2023

Graphite is an allotrope of carbon with a wide variety of uses. Moreso, graphite is quite economical to manufacture, and because of this, we can find it as a major ingredient in almost all of our household items, e.g., pencils, batteries, etc. So in this guide, we will talk about graphite and find out whether graphite is flammable.

What Is Graphite?

Graphite, which you can also call “plumbago,” is a crystalline form of carbon that has its atoms arranged in a hexagonal structure. Each layer present in the hexagonal makeup of the graphite is known as “graphene.”

Moreover, graphite is a great conductor of heat and electricity because of its ability to produce free mobile valence electrons. Likewise, graphite is the most prevalent and the most stable form of carbon known.

And owing to its layered structure, it is suitable for lubricants. Graphite can also be used as a reflector or moderator to protect the nuclear reactor against extremely high temperatures.

Graphite has various applications in the production of electrodes, brake linings, collaboration with iron to form steel, and the manufacture of lead in pencils. Now, let’s throw ourselves an important question, is graphite flammable?

And by the way, can graphite pose a fire hazard to our homes? We will find out soon.

Is Graphite Flammable?

Yes, graphite is flammable, however, it will not burn in its solid form. Graphite dust ignites at a relatively high temperature of about 752°F or even more sometimes.

Owing to this high ignition temperature, graphite is considered a flammable substance. But don’t sweat it, provided you don’t mess with any source of open fire around graphite products, you’re safe.

Does Graphite Catch Fire?

A resounding yes! Graphite catches flames. In the right conditions (when exposed to sparks and in the presence of air), graphite will ignite at a temperature of about 752°F.

On the other hand, graphite auto-ignites at a higher temperature close to 1022°F.

Is Pencil Graphite Flammable?

Pencil graphite is not flammable, however, it can combust at high temperatures. Thus, pencil graphite is non-flammable but combustible.

Does Graphite Burn?

This question is straightforward. Since every flammable substance can burn, the short answer is yes, graphite can burn.

Although it might be hard to burn graphite because its carbon atoms are bound by strong covalent bonds. However, once these bonds are broken down by subjecting them to extreme heat, it will be easier for graphite to burn.

What Happens When You Heat Graphite?

Unlike most flammable substances, graphite has a very low linear thermal expansivity, it will not expand even when heated at intense temperatures. And because of this, graphite is described as being thermally stable.

Note that burning graphite at any temperature around 1292°F reacts with atmospheric oxygen to give off carbon monoxide (a poisonous gas) and carbon dioxide as byproducts. But when oxygen is not available, hot graphite will withstand the heat and will not burn.

This is one property that makes graphite a good choice as a moderator in fiery furnaces and nuclear reactors.

Does Graphite Melt?

Graphite can melt but only when it is subjected to a considerably high temperature. The melting point of graphite is about 6512°F.

Can Graphite Boil?

Almost all forms of carbon (eg, diamond and graphite) boil at a higher temperature. The boiling point and melting point of graphite are closer in value.

Graphite can boil no matter how strong it is once its cohesive forces are overcome. Typically, graphite boils at a temperature of about 6746°F.

Owing to the close range of the boiling point and melting point of graphite, this substance loses its liquid phase. That is, graphite transforms directly from its solid form to its gaseous state in a process known as sublimation.

Is Graphite Explosive?

In certain cases, graphite can explode. Graphite dust has a higher surface-area-to-volume ratio when compared to bulk graphite. As a result, it reacts easily and violently with strong oxidizers like potassium peroxide, fluorine, chlorine dioxide, etc.

Thereafter, the bonds in graphite will be weakened, thus, it will catch fire readily and explode in the presence of air and any ignition sources.

Is Graphite Toxic?

When consumed, graphite is not toxic or poisonous, unlike carbon. Often, most people misinterpret graphite as the lead in pencils, and since lead is harmful when consumed even in low quantities, they assume graphite is also toxic.

However, this is not so true. Graphite is only a component of pencil leads and not the whole lead element. Thus, it possesses no characteristics of lead.

Similarly, breathing in graphite is not harmful to one’s health. But sometimes, if you inhale graphite powder for a long time and in high doses, it might trigger a condition known as “graphite pneumoconiosis.”

Graphite pneumoconiosis is a serious health condition with life-threatening symptoms such as trouble breathing, blockage of bronchial tubes, etc.

Can You Use Graphite As Fuel?

Not really… Graphite has a low calorific value and a high ignition point. So, if you intend to use graphite as fuel just like crude oil, it might take a lot of time and require considerable joules of energy before it combusts.

Hence, graphite in any form is not suitable to be used as fuel.

How To Put Out Graphite Fire

Depending on the intensity of graphite fire, you can extinguish it in a lot of ways. However, the most effective way to put out graphite fire is by cutting off the source of air or oxygen to the fire.

Once the oxygen supply to graphite fire has been disabled, it will be easy to quench the flames with ordinary water or a fire blanket. You can as well seek the services of firefighters if you don’t know how to go about blocking the oxygen source.

Final Recommendations.

Graphite, most especially its powder form, can catch flames, but it is not very flammable in the real sense. If graphite products are stored appropriately away from open flames, you will be safe with them because they are not likely to ignite at room temperature and in an oxygen-deprived environment.

This guide features everything you should know about graphite and its flammability. You can also visit here to study the safety data sheet for graphite.


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