Difference Between Cial and Charcoal
People have known since prehistoric times that coal is a rock that burns. Only within the past two centuries, however, has this material become a vital part of the world’s energy picture. Today, coal is one of the most widely used sources of power in the world, particularly as a fuel for the steam turbines that generate electricity; it is also used for heating purposes. One particularly important coal by-product, called coke, is used in the manufacture of steel and in the processing of many other metals. Coal can also be treated to yield both gaseous and liquid fuels, and it is the source of a variety of manufactured chemicals.
Coal is actually a mixture of substances, and is thus classified as a rock rather than a mineral. Coal contains volatile matter (material that can be easily vaporized), moisture, and a varying amount of fixed carbon—the solid material that burns after the volatile matter and moisture have been driven off. There is also a certain percentage of ash—the material that remains after burning has occurred.
Coal was formed from the remains of plants that have undergone a series of far-reaching changes. When small pieces of coal are viewed under the microscope, evidence of fibers, spores, and other elements of plant-cell structure can be identified.
Charcoal is a porous and amorphous form of carbon prepared by destructive distillation techniques on carbonaceous materials. It may be prepared from wood, bone, corn cobs, rice hulls, nutshells, fruit seeds, and vegetable wastes such as bagasse and lignin.
In commercial plants, the raw materials are carbonized in retorts or kilns, and the by-products of the process, such as acetic acid and methyl alcohol, and wood tar, are collected by condensation and then further distilled and purified.
Charcoal is used to some extent as a domestic fuel, both for heating and cooking. Because of its low sulfur content, it is used to replace coke in the processing of some types of iron. Wood charcoal is also used for making black gunpowder, for carburizing steel, in the production of calcium carbide, sodium cyanide, and carbon tetrachloride, and for making arc electrodes.
Activated charcoal is produced by heating animal bones or certain types of vegetable charcoal to temperatures of 800 to 900° C (1470–1650° F) in steam or carbon dioxide. In the form of an adsorbent powder, activated charcoal is used to decolorize sugar and to purify drinking water, oils, and a variety of substances in the chemical, food, and pharmaceutical industries.
The granular form of activated charcoal is used to adsorb gases in the purification of chemicals and industrial gases. It is used in air conditioning systems to remove odors and irritants. Activated charcoal, in conjunction with chemicals, is used in industrial and military gas masks. In the exhaust systems and coolant gas systems of nuclear reactor installations, activated charcoal adsorbs and holds radioactive contaminants until the isotope decays.