Other uses of coal, petroleum and natural gas:
Most of us think petroleum is a source of fuel. But advances in our understanding of various chemical processes has led to the use of both coal and petroleum as the starting materials for a wide variety of products.Petroleum is a complex mixture. It is separated into various components by a separation technique known as fractional distillation .
We can see the various products which are now being obtained from petroleum. Initially, the separation techniques available were not advanced and could separate only a few components from the petroleum mixture. One of the first fractions to be separated from petroleum was kerosene which was found to be better fuel than the petroleum.Now, we can separate many more components. Fuel gas, petrol, diesel etc. are all obtained from petroleum mixture. These components of petroleum are then used to obtain other products.
Identifying various uses of petroleum:
Coal:
Coal is not as versatile as petroleum but it is also very useful.We can see that coal gives us coke, coal tar and coal gas. Each of these components has several uses.When coal is heated in air, it burns and produces mainly carbon dioxide gas.Coal is processed in industry to get some useful products such as coke, coal tar and coal gas.
Coke:
It is a tough, porous and black substance. It is an almost pure form of carbon. Coke is used in the manufacture of steel and in the extraction of many metals.
Coal tar:
It is a black coloured thick liquid with an unpleasant smell. It is a mixture of about 200 substances. Products obtained from the coal tar are used as starting material for manufacture of various substances like Synthetic dyes, drugs, explosives, perfumes, plastics, paints, and roofing materials etc. Interestingly naphthalene balls used to repel moths and other insects are also obtained from coal tar.
Coal gas:
Coal gas is obtained during the processing of coal to get coke. It is used as a fuel in many industries situated near the coal processing unit.
Petrochemicals: The useful substances which are obtained from petroleum and natural gas are called petro chemicals. These are used in the manufacture of detergents, synthetic fibers (Polyester,Nylon ,Acrylic polythene etc). (Due to its great commercial importance petroleum is also called as liquid gold).