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A C - H bond
is formed by mutual sharing of an electron and hence when bond
breaks no electron is released , instead energy is released in the
form of heat.
To break a molecular bond, amount of energy is provided (which is
done by igniting the fuel). The energy provided is activation
energy. When activation energy is provided to the fuel molecule, the
C- H bond breaks and releases heat energy.
When a bond breaks the electron shared by carbon and hydrogen atom
goes back to the hydrogen atom. An electron goes into K orbit of the
H atom, which is the lowest energy state. When electron is in
covalent bond it has more energy than the energy it has in the
lowest energy orbit. When bond breaks the energy in SP2
hybridized orbit is not sufficient for an electron to escape from
the atom, hence electron emits the extra energy in the form of heat
and jumps to the lower Energy State. Therefore the hydrocarbon fuel
gives energy in the form of heat.
To extract energy from hydrocarbon fuel in the form of electricity,
the shared electron in C - H bond should have sufficient energy so
that it can escape from H atom leaving behind an H+ ion. (the free
electron and H+ ion form an electric current source)
To make an electron jump out of C - H bond, the electron need
sufficient amount of energy from which is provided from outside.
(catalytic quantum of energy)
The catalytic quantum of energy provided from outside makes an
electron 'stronger ' to escape from the hydrogen atom.
If this is achieved then the electron has energy that is equal to
sum of bond energy plus the catalytic quantum of energy provided
externally.
Thus
Energy of an electron = Catalytic quantum + Bond
energy
The catalytic energy quantum provided externally is used repeatedly
to extract bond energies of fuel molecules in the form of a free
electrons (electrical energy).
The catalytic quantum used for the next energy conversion is
generated from the energy extracted before (hence the energy quantum
to be provided from outside is catalytic quantum).
To extract the bond energy of C - H bond in electrical form, the H
atom in the carbon hydrogen molecule should be ionized so that an
electron and an H+ ion is obtained that forms an electric current.
Ionization energy for an isolated H atom is 1310 kJ / mole.
for one H atom, ionization energy is 2.1749 x 10-18 J/
atom
When hydrogen forms a bond with carbon atom, the shared electron
has some energy in the bond.
The energy in one C -H bond is 0.3699 x 10-18 J / bond
.
The electron gets the energy stored in the bond but this amount of
energy is not sufficient for electron to become a free electron.
Hence to ionize the H atom amount of external energy is provided
which is equal to the difference between the bond energy of C - H
bond and ionization energy of the H atom.
=> Ionization energy - Bond energy = Catalytic quantum
(2.1749 x 10-18) J/ atom - (0.3699 x 10-18)
J/ CH bond = 1.805 x 10-18 J/ atom
Thus the external energy provided is 1.805 x 10-18 J /
atom.
i.e. per C-H bond since each bond has one hydrogen atom.
The energy is provided in the form of electromagnetic waves. The
frequency and wavelength of the electromagnetic wave is,
E= hf, Where; E= energy of wave, h= Plank's constant, f= frequency
of wave.
1.805 x 10-18 J = 6.625 x 10-34 x
frequency of wave
Hence f= 2.7 x 1015 cycles / second therefore
wavelength is c/f,
c = speed of electromagnetic wave = 2.97 x 108 m/s
wavelength is 1.090 x 10-7 m = 10900 A
unit.
The wave of the wavelength 10900 A is an ultraviolet wave
An electron in C
- H bond has only 17% (0.3699 x 10-18) of the energy
required to become a free electron. The remaining 83% (1.805 x 10-18
J ) energy is provided from externally in the form of
electromagnetic waves.
Energy in C - H bond + External catalytic quantum = ionization
energy H + ion
17 % 83
% 100 % and
electron e
The catalytic quantum of energy does not form the part of energy to
be used and it is used to extract the energy in the electrical form
Working:
The chemical energy stored in Carbon-Hydrogen bonds of liquid
hydrocarbon fuel molecule is converted into electrical energy. The
liquid hydrocarbon fuel is exposed to collimated electromagnetic
waves in absence of air. The wavelength of incident collimated
electromagnetic wave is 1090o A units(1090 x 10-10
m). The electromagnetic wave give its energy to the electron that
forms the chemical bond between Carbon and Hydrogen. The electron in
the Carbon - Hydrogen bond absorbs the energy and goes out of the
hydrogen atom. After an electron goes out of Hydrogen atom, the
Hydrogen atom becomes a positive Hydrogen ion. An electron, which
goes out of Hydrogen atom, becomes a free electron. The liquid fuel
is kept in a magnetic field while it is exposed to electromagnetic
waves. The magnetic field directs these free electrons towards a
metal plate, that acts as a metal electron collector and as an
electrode. The positive Hydrogen ions are directed towards a
synthetic membrane (proton exchange membrane). The synthetic
membrane passes only positive Hydrogen ions through it. While
passing through the membrane, positive Hydrogen ion gains an
electron from the membrane and combines with Oxygen atoms in the air
which is on the other side of the membrane (the Hydrogen ion gives
it's positive electrical charge to the membrane).
The membrane, which also acts as an electrode, gets positive
electrical charge and the metal electron collector becomes
negatively charged due to excess electrons that are collected on the
metal plate. The two electrodes are connected through an electrical
circuit. An electrical current flows through the circuit, which is
energy source for useful purpose.
The electromagnetic waves of 10900 A unit gives a
quantum of energy equals to
1.805 x 10-18 J.
(E = hf, E = energy of wave, h= plank's constant, f= frequency of
the wave,
f= c/ wavelength , c = speed of electromagnetic wave )
The energy quantum is added to the energy that an electron has in
Carbon-Hydrogen bond. An electron has energy equal to 0.3699 x 10-18
J in the Carbon - Hydrogen bond. Now the electron has the
total energy equal to sum of the two energy quanta
that is [( 1.805 x 10-18 ) + ( 0.3699 x 10-18
) ] J = 2.1749 x 10-18 J.
This energy is sufficient for an electron to go out from the Carbon
- Hydrogen bond leaving behind an unstable Carbon, positive Hydrogen
ion, and become a free electron.
The Carbon is collected at the bottom of the fuel container.
Part of the electrical energy is consumed to generate
electromagnetic waves that are used for energy conversion and
remaining part of energy is available for use.
IN THE DRAWING I
'1 ' is collimated electromagnetic wave source.
'2' is fuel molecule.
'3' is proton exchange membrane that passes only positively
charged Hydrogen
ions.
'4' is a metal electron collector.
'5' are permanent magnets .
'6' is a fuel container .
'7' is a waste Carbon collected at the bottom of container.
'8' is a continues airflow.
'9' is a water molecule formed at the outer side of the membrane .
'10' is Minimum fuel level.
'11' is a battery in which the converted electrical energy is stored
.
'12' is liquid hydrocarbon fuel.
13 is collimated electromagnetic wave.
USES
This conversion process is useful in automobiles in which liquid
hydrocarbon fuel is used. The automobiles use an internal combustion
engine to generate kinetic energy from fuels. The losses involved
in internal combustion engines are about 60%.
The Direct Energy
conversion system for hydrocarbon fuel would provide a better option
to an Internal Combustion Engine, thus avoiding energy losses and
pollution.
CALCULATIONS
1.
For CH4 i.e. , the caloric value is
55700 kJ/ Kg.
Molecular weight of methane ( CH4 ) is
{ (12 x 1) + ( 1 x 4 ) } = 16
Since CH 4 delivers 55700 kJ/ Kg = 55700 J/g
Hence one mole of methane delivers 55700 J x 16 = 891200 J/
mole.
Each mole contains 6.023 x 1023 molecules,
Energy delivered per molecule is = (891200 / 6.023 x 1023
)J / molecule .
= 1.4796 x 10-18 J / molecule.
Each molecule of CH 4 has four C H bonds
Therefore one C- H bond in methane has energy
(
1.4796 x 10-18 ) / 4 = 0.3699 x 10-18 J/ C
H bond.
When one C-H
bond breaks the amount of energy released is 0.3699 x 10-18
J
------------------------- I
2.
The ionization energy of an isolated Hydrogen atom is
1310 kJ / mole = 1310000 J / mole
Hence ionization energy per atom is (1310000 / 6.023 x 1023)
J / atom
= 2.1749 x 10-18 J /
atom ------------------------II
From I
one C-H bond has energy equal to 0.3699 x 10-18
J
From II
. one-H atom needs 2.1749 x 10-18 J to get
ionized.
When C-H bond breaks, to ionize H atom (to extract an electron from
H atom) an amount of energy to be provided from outside is equal to
the difference between ionization energy of isolated Hydrogen atom
and the energy stored in the C - H bond.
That is catalytic energy quantum = ionization energy C-H bond
energy
= 2.1749 x 10-18 J/C-H bond - 0.3699 x
10-18 J/C-H bond
Catalytic energy
quantum = 1.805 x 10-18 J/C-H bond.
The energy provided from outside enables the electron (shared by
carbon and hydrogen atom in C-H bond) to escape from the H atom
leaving behind an H+ ion and carbon. The electron and an H+ ion are
used to form an electric current.
The external energy (catalytic quantum) is provided in the form of
electromagnetic waves where energy of wave = 1.805 x 10-18
J
Since ,
Energy = h x frequency of wave, h = Planks constant = 6.625 x 10-34
1.805 x 10-18 J = 6.625 x 10-34 x
frequency
hence, frequency = 2.724 x 1015 cycles per second.
speed of an electromagnetic wave is 2.97 x 108 m /s
the wavelength of
the wave = ( 2.97 x 108 /
2.724
x 1015 ) m.
= 1090 x
10-10 m = 1090 0 A.
Thus the wavelength of the wave to be used to provide the catalytic
energy quantum is 1090 0 A. As this wavelength is more
than 70000 A, it is in the ultraviolet spectrum.
Following are the
details of the energies for different fuel quantities
When 1 gm octane is used, it delivers energy equal to 35170 J by
breaking C-H bonds
The catalytic energy quanta needed is 171650 J
It generates 206824 J in the form of electricity that is catalytic
quanta and C-H bond energy together.
Total electrical energy - Catalytic quanta = Energy available for
use.
To generate 1 kW energy the catalytic energy quanta needed is
(171650 / 35170) J
= 4.8796 times the energy needed i.e. 4.8796 kW
Thus catalytic quanta to be provided is 4.8796 times the amount of
energy needed from octane |