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_: At present, about 80% of the world's demand for transportation fuels - road, rail, air and sea - is met by derivatives from the fossil fuel, petroleum. Petrol, one of the major derivatives of petroleum, is used throughout the world as a motor vehicle fuel.
Other petroleum derivatives including diesel and liquid petroleum gas can be used in motor vehicles as alternatives to petrol as can compressed natural gas, which often occurs in conjunction with petroleum deposits. Some alternatives are derived from non- fossil, or partly renewable, sources such as grain or other agricultural crops. However, these need fertilizers made from fossil fuels etc. and are not, therefore, totally renewable.
The major fossil fuel alternatives to petrol are:
diesel
liquid petroleum gas (LPG)
compressed natural gas (CNG)
ethers - methyl tertiary butyl ether (MTBE) produced from natural gas and butane
electricity from coal /oil /gas and
methanol produced from natural gas or coal ,
Non- Fossil fuel are given below:
nuclear fission and fusion
geothermal power
hydropower
tidal power
ocean currents and temperatures
wind
solar
biomass
Hydrogen Economy
PETROL AS A FUEL and ITS HISTORY
Early refineries used a simple distillation process to separate crude oil into its components according to their boiling points. The petrol produced by this method was only that naturally occurring in the crude oil.
As demand for motor spirit grew, engineers and chemists found that more severe heating of the higher boiling points hydrocarbons broke them down, or 'cracked' them, into smaller, lower boiling hydrocarbons more suitable for petrol production. From 1913, thermal cracking was used to increase petrol production.
Substances known as 'catalysts' were later found to do a better job of cracking hydrocarbons than heat alone, by speeding up the reaction and producing a greater yield of higher octane petrol.
CHEMISTRY OF PETROLEUM (FOSSIL FUEL)
Petrol is a derivative of petroleum. It is essentially a complex mixture of hydrocarbons that boils below 18Oo C. The hydrocarbon constituents are those that have 4-12 carbon atoms in their structure and fall into three general types:
Paraffins, such as hexane (C6H14) , and octane (C8H18)
Olefins, such as hexene (C6H12)
Aromatics, such as benzene (C6H6) and toluene
Petrol consists of a blend of more than 200 such hydrocarbons either...