'Petroleum.'
Petroleum is also known as crude oil. Petroleum naturally seeps to the Earth's surface along fault lines and cracks in rocks, where it gathers in pools as tar, asphalt or bitumen. From this property it gets its name: the Latin petra, meaning 'rock' and oleum, meaning 'oil', 'rock oil'. Crude oil deposits are found all over the world. Petroleum in a solid form is called asphalt. In liquid form petroleum is called crude oil and in a gaseous form is called natural gas. Petroleum is a mixture of organic compounds containing just two elements: carbon and hydrogen and is the most important natural source of fuel, it is also the source of the raw materials used to make detergents, plastics, paints, anti-freeze, synthetic rubber and medicines.
Crude oil is a mixture of different hydrocarbons and can be broken down into separate fractions by a process called fractional distillation. The majority of compounds in crude oil are straight alkanes, but the mixture also contains cycloalkanes and arenas. Separation is possible because individual hydrocarbons in the fractions all have different boiling points. As the alkane carbon chain increases in length, the boiling point increase. Fractional distillation takes place in an oil refinery, in a fractionating column. Before the crude oil reaches the fractionating column it is heated until it vaporises. The temperature at the bottom of the column is higher than at the top, this creates a temperature gradient, so different fractions can be drawn off at different levels. The temperature at the bottom of the column is about 340?C and the temperature at the top is about 110?C. Any hydrocarbons that remind liquid at the temperature 340?C will fall to the bottom of the column and are removed as residue, this contains useful materials such as lubricating oil. The different fractions are collected when a particular hydrocarbon reaches the level in the column where the temperature is equal to its boiling point, it then changes state from a gas to a liquid and is collected in trays. Only the hydrocarbons with a lower boiling point than 110?C reach the top of the column. This the primary distillation of crude oil and it does not separate the individual hydrocarbons, but it separates them into fractions with the same boiling points within a specific range. To obtain purer products, secondary distillations are carried out on the fractions. The major fractions of crude oil are:
Petroleum is also known as crude oil. Petroleum naturally seeps to the Earth's surface along fault lines and cracks in rocks, where it gathers in pools as tar, asphalt or bitumen. From this property it gets its name: the Latin petra, meaning 'rock' and oleum, meaning 'oil', 'rock oil'. Crude oil deposits are found all over the world. Petroleum in a solid form is called asphalt. In liquid form petroleum is called crude oil and in a gaseous form is called natural gas. Petroleum is a mixture of organic compounds containing just two elements: carbon and hydrogen and is the most important natural source of fuel, it is also the source of the raw materials used to make detergents, plastics, paints, anti-freeze, synthetic rubber and medicines.
Crude oil is a mixture of different hydrocarbons and can be broken down into separate fractions by a process called fractional distillation. The majority of compounds in crude oil are straight alkanes, but the mixture also contains cycloalkanes and arenas. Separation is possible because individual hydrocarbons in the fractions all have different boiling points. As the alkane carbon chain increases in length, the boiling point increase. Fractional distillation takes place in an oil refinery, in a fractionating column. Before the crude oil reaches the fractionating column it is heated until it vaporises. The temperature at the bottom of the column is higher than at the top, this creates a temperature gradient, so different fractions can be drawn off at different levels. The temperature at the bottom of the column is about 340?C and the temperature at the top is about 110?C. Any hydrocarbons that remind liquid at the temperature 340?C will fall to the bottom of the column and are removed as residue, this contains useful materials such as lubricating oil. The different fractions are collected when a particular hydrocarbon reaches the level in the column where the temperature is equal to its boiling point, it then changes state from a gas to a liquid and is collected in trays. Only the hydrocarbons with a lower boiling point than 110?C reach the top of the column. This the primary distillation of crude oil and it does not separate the individual hydrocarbons, but it separates them into fractions with the same boiling points within a specific range. To obtain purer products, secondary distillations are carried out on the fractions. The major fractions of crude oil are:
