Most of the time, activated charcoal and activated carbon refer to the same substance, a blackish powder that has been heated to enhance its adsorption abilities. There are, however, slight differences between charcoal and carbon. Charcoal, which is often the result of burning wood and other organic materials, is primarily composed of carbon atoms. But it will have impurities such as water and various organic substances. Pure carbon, on the other hand, can be found in two radically different forms, diamond and graphite. The difference between diamond and graphite lies in the arrangement of the atoms. The graphite arrangement is the same one that is found in charcoal. This is why activated charcoal and activated carbon usually mean the same thing.
There are many ways to produce activated charcoal or activated carbon. For example, pyrolysis is a common process of producing pure activated carbon. The ordinary charcoal is exposed to inert gases, such as nitrogen gas and argon, at extremely high temperatures, about 600 degrees Celsius. These gases don’t react with the charcoal but they do encourage the release of impurities such as hydrogen gas and methane. What is left behind is a heated substance made of pure carbon. The high energy atoms of the activated carbon can be compared to empty and hungry shelves. Why empty? Because the impurities have been removed. Why hungry? Because the carbon would seek out materials that would fill these shelves.
From the purely scientific point of view, these “shelves” are better known as the surface area. The activated charcoal will have a greater surface area than the ordinary charcoal. This surface area will attract materials such as vapors and fine particles. When finer particles gets stuck to the surface area, the event is called adsorption. Adsorption is different from absorption. To differentiate between the two, visualize a sponge. Absorption occurs when the sponge is soaked with water. On the other hand, adsorption occurs when dirt and grime gets stuck on the surface of the sponge. Activated carbon is similar to a sponge that can adsorb more particles than any other substance.
The great adsorption ability of activated charcoal or activated carbon is useful in many ways. For example, the activated charcoal is placed in air filters and gas masks so that it can adsorb foul-smelling fumes. Activated carbon is placed in water purifiers to adsorb and trap bacteria and particulates. And activated charcoal is used to treat poisons. The surface area of the activated carbon will adsorb and immobilized the toxins.