Petroleum
Graphene
• is an allotrope of carbon consisting of a
single layer of atoms arranged in a two-
dimensional honeycomb
lattice nanostructure.
• The name is derived from "graphite" and
the suffix -ene, reflecting the fact that
the graphite allotrope of carbon contains
numerous double bonds.
• It is strong and flexible
• It allows electrons to flow across its
surface
• Its electrical conductivity is high
• It is the starting point for making
nanotubes. One of the uses for nanotubes
is for drug delivery
Petroleum
• Petroleum, also known as crude oil and oil, is a naturally occurring, yellowish-
black liquid found in geological formations beneath the Earth's surface.
• When prehistoric marine animals died, they sank to the sea bed and were
covered by mud. High pressure, high temperature and the action of bacteria over
millions of years changed it into petroleum and natural gas
• The original organic material broke down into hydrocarbons
• The compression of the material transformed it into shale. The geological
movements and pressure turned the shale into harder rocks and squeezed out
the oil and gas.
• The oil and gas moved upwards through the porous rock, moving from high
pressure to low pressure conditions.
• They are often trapped by a layer of non-porous rock
• https://youtu.be/PYMWUz7TC3A
Oil rig
Fractional distillation
• Petroleum/ crude oil – is made of hydrocarbons which are mainly hydrogen (about
13% by weight) and carbon (about 85%). Other elements such as
nitrogen (about 0.5%), sulfur (0.5%), oxygen (1%), and metals such as
iron, nickel, and copper (less than 0.1%) can also be mixed in with the
hydrocarbons in small amounts.
• The way molecules are organized in the hydrocarbon is a result of the
original composition of the algae, plants, or plankton from millions of
years ago. The amount of heat and pressure the plants were exposed to
also contributes to variations that are found in hydrocarbons and crude
oil.
• Most of the petroleum is used to make fuel but about 10% is used to
make feedstock in the chemical industry
• Before being used, the various hydrocarbons are separated by
refining ,i.e: fractional distillation, in an oil refinery
Oil refinery
• An oil
refinery or petroleum
refinery is an industrial
process plant where petrole
um (crude oil) is transformed
and refined into useful
products such
as gasoline (petrol), diesel
fuel, asphalt base, fuel
oils, heating
oil, kerosene, liquefied
petroleum
gas and petroleum naphtha.
Fractional distillation
• At a refinery, petroleum is separated into different fractions based on their boiling points. These
boiling points are related to the number of carbon atoms in the molecule
• Fractions are divided into 3 categories:
• Light distillate is one of the more important fractions, and its products have boiling points around
70-200°C. Useful hydrocarbons in this range include gasoline, naphtha (a chemical feedstock),
kerosene, jet fuel, and paraffin. These products are highly volatile, have small molecules, have low
boiling points, flow easily, and ignite easily.
• Medium distillate are products that have boiling points of 200-350°C. Products in this range
include diesel fuel and gas oil - used in the manufacturing of town gas and for commercial heating.
• Heavy distillate are the products with the lowest volatility and have boiling points above 350°C.
These fractions can be solid or semi-solid and may need to be heated in order to flow. Fuel oil is
produced in this fraction. These products have large molecules, a low volatility, flow poorly, and do
not ignite easily.
• In addition there are -At the very top of the tower are the gases that are too volatile to condense,
such as propane and butane. At the bottom are the "residuals" that contain heavy tars too dense
to rise up the tower, including bitumen and other waxes.
• Lighter fractions such as gasoline(petrol), the
demand is greater than the supply. The opposite
applies for heavy fractions like kerosene and diesel Catalytic cracking
• Catalytic cracking :Large molecules can be broken
down into smaller molecules . This can be done by
heat, pressure or catalyst
• Cracking of petroleum yields light oils
(corresponding to gasoline), middle-range
oils used in diesel fuel, residual heavy oils,
a solid carbonaceous product known
as coke, and such gases
as methane, ethane, ethylene, propane, pr
opylene, and butylene. Depending on the
end product, the oils can go directly into
fuel blending
• C10H22 ---Heat/catalyst------>C8H18 + C2H4
decane octane + ethene
• But-1-ene and propene may also be produced
• Catalyst: silica/ alumina/zeolites
Blending gasoline
• Some products from cracking are
added to gasoline to improve the
quality of petrol
• As many as 12 different
components may be used in a
blend of petrol
• Gasoline blending is a refinery
operation that blends different
component streams into various
grades of gasoline. Typical grades
include 83 octane.
Knocking
• Knocking: in an internal-
combustion engine, sharp
sounds caused by
premature combustion of
part of the compressed
air-fuel mixture in
the cylinder. In a properly
functioning engine, the
charge burns with the
flame front progressing
smoothly from the point
of ignition across the
combustion chamber
