The word petroleum is derived from the Latin words petra (rock) and oleum(oil). Thus, petroleum is an oil obtained from rocks. Petroleum is a mixture of hydrocarbons (i.e.hydrogen and carbon).
Petroleum is one of the important sources of power. The demand of petroleum has increased tremendously during the last few years. Petroleum is one of the largest of all chemical industries. It not only provide fuels (kerosine, gasoline, diesel etc.) but the consumer products like wax, lubricating oils etc.
Petrochemicals include a wide range of various substances like fertilizers, expolsives, carbon black, pigments, synthetic rubber, plastics etc.
Petrochemicals are chemical products derived from petroleum. Some chemical compounds made from petroleum are also obtained from other fossil fuels such as coal or natural gas or renewable sources such as corn or sugar cane.
Occurance of petroleum :
Petroleum is found Normally at great depth underground or below seabeds. Petroleum and natural gas are formed by the anaerobic decomposition of remains of organism including phytoplankton and zooplankton that settle to the sea or lake bottom in large quantities under anoxic conditions.
Millions of year ago, over geological time this organic matter mixed with mud, got buried under heavy layers of sodiment.
Petrochemicals occur in fossil fuels. They are formed by natural processes such as anaerobic decomposition of buried dead organisms. The age of the organisms and their resulting fossil fuels is typically millions of years. It contains high percentage of carbon and include coal, petroleum and natural gas.
Fuel:
Fuels are naturally occurring or manufactured combustible organic substances which acts as heat energy or as a raw material for the chemical industry. Major petrochemicals are used as fuel.
Industries require power for their routine operations. Heat energy is the main source of power. Therefore, those materials used for production of heat energy are termed as fuels.
A fuel can be defined in different ways:
* Any source of heat energy is called as fuel.
*Any substance which by oxidation, is made a source of heat for practical purposes is called as fuel.
*Any combustible substance which may be burnt to supply heat that can be used economically for domestic and industrial purposes.
It is now well established fact that, it is not necessary for a fuel to undergo combustion or oxidation. Electrical energy when used as a source of heat is also called fuel. Nuclear energy may also be used as a source of heat. A fuel is any fissionable material which produces energy in a form that can be used for producing power.
Artificial or synthetic fuel is prepared by processing natural fuel by different ways.
Natural fuels like coal, wood shale, peat, petroleum, natural gas etc. are known as primary fuels whereas as coke, charcoal, petrol, kerosine, coal tar, producer gas, coke-oven gas, compressed butane etc, are called secondary fuels. Secondary fuels therefore, produced by processing primary fuels.