22-02-2013, 10:03 AM
Combustion Theory
[attachment=51400]
Molecules and Covalent Bonds
Chemical bonds result from a mutual sharing of electrons between atoms,
the shared electrons are in the outermost shell, known as valence electrons
Atoms like to have electron configuration like noble gas, usually eight valence
electrons, an octet.
Alcohols
An alcohol molecule is simply a hydrocarbon molecule with one of the
hydrogen atoms replaced by a hydroxyl molecule (OH)
The main alcohols used as engine fuels are:
Ethanol – ethyl alcohol (C2H5OH) consists of ethane molecule (C2H6) with
OH substituting one H
Methanol –methyl alcohol (CH3OH) consists of methane molecule (CH4)
with OH substituting one H
IC Engine Fuels
The purpose of refining is to separate crude oil into various fractions via
a distillation process, and then chemically process the fractions into fuels
and other products.
A still is used to heat a sample, preferentially boiling off lighter
components which are then condensed and recovered.
The group of compounds that boil off between two temperatures are
referred to as fractions.
Gasoline
Light virgin (or straight run) naptha can be used as gasoline.
Gasoline fuel is a blend of hydrocarbon distillates with a range of boiling
points between 25 and 225oC (for diesel fuel between 180 and 360oC)
Chemical processing is used to:
Produce gasoline from a fraction other than light virgin, or
Upgrade a given fraction (e.g., Alkylation increases the MW and octane
number of fuel: produce isooctane by reacting butylenes with isobutane in
the presence of an acid catalyst)
[attachment=51400]
Molecules and Covalent Bonds
Chemical bonds result from a mutual sharing of electrons between atoms,
the shared electrons are in the outermost shell, known as valence electrons
Atoms like to have electron configuration like noble gas, usually eight valence
electrons, an octet.
Alcohols
An alcohol molecule is simply a hydrocarbon molecule with one of the
hydrogen atoms replaced by a hydroxyl molecule (OH)
The main alcohols used as engine fuels are:
Ethanol – ethyl alcohol (C2H5OH) consists of ethane molecule (C2H6) with
OH substituting one H
Methanol –methyl alcohol (CH3OH) consists of methane molecule (CH4)
with OH substituting one H
IC Engine Fuels
The purpose of refining is to separate crude oil into various fractions via
a distillation process, and then chemically process the fractions into fuels
and other products.
A still is used to heat a sample, preferentially boiling off lighter
components which are then condensed and recovered.
The group of compounds that boil off between two temperatures are
referred to as fractions.
Gasoline
Light virgin (or straight run) naptha can be used as gasoline.
Gasoline fuel is a blend of hydrocarbon distillates with a range of boiling
points between 25 and 225oC (for diesel fuel between 180 and 360oC)
Chemical processing is used to:
Produce gasoline from a fraction other than light virgin, or
Upgrade a given fraction (e.g., Alkylation increases the MW and octane
number of fuel: produce isooctane by reacting butylenes with isobutane in
the presence of an acid catalyst)