On The Production
of Hydrogen Gas
By The Electrolysis
of Water
Johnston
Page 4
To summarize up to this point; we have seen that the energy to
separate the water molecules in our solution of electrolyte and water
comes from the interaction between the molecules of water and the
molecules of the electrolyte and occurs BEFORE any electric current
is created or added. We have seen that, for every electron that
enters the cell or battery at the cathode, another electron from the
solution must EXIT at the anode. If these two reactions do not
happen, then all reactions stop.
This finding is the basis of Faraday's law of electrolytic
conduction which states; "The amount of gasses evolved is equal to
the amount of current which passes". It is obvious at this point that
it cannot be any other way because conduction of electricity from one
side of a cell to the other cannot take place unless H2 gas is
evolved by reduction at the cathode and O2 by oxidation at the anode,
releasing a quantity of energy that is EQUAL to the amount of that is
"used" to evolve H2 at the cathode. Equilibrium must be maintained.
My trusty chemistry book describes the process of electrolysis in the
following way; "In order to maintain an electric current, it is
necessary to have a complete circuit, i.e., there must be a closed
loop whereby the electric charge can return to it's starting point.
If the complete circuit includes as one component an electrolytic
conductor, chemical reaction must occur."
"Electrons are crowded onto the cathode and drained away at the
anode. The circuit is not complete unless there is some way by which
electrons can be used up at the cathode and formed at the anode.
Chemical changes must occur."
"At the cathode, a reduction process must occur in which some
ion or molecule accepts electrons and is thereby reduced. At the
anode, electrons must be released by an ion or molecule to the
electrode. An oxidation process must occur."
That this is true is obvious to anyone who has ever constructed
a simple electrolysis cell. The "problem" then is that, when you
operate an electrolysis cell, you are, by the very nature of the
reaction, releasing from the cell double the amount of energy which
actually enters the cell in the form of electric current. This input
energy is transformed into and "stored" as the potential chemical
energy of H2(g) and as a consequence of this reaction, to maintain
chemical equilibrium within the solution, an equal amount of electric
current is released at the anode. Faraday explained this phenomenon
by calling the gasses that are produced a secondary effect
(by-product) of the electrolytic conduction process.
If we consider again the remaining reactants after a complete
cycle of electrolysis, in such a cell as the example I have been
using up to this point, we find that we are left with our initial SO3
molecule which has now given up it's extra oxygen atom. What does it
do now? Simple, it breaks up ANOTHER H2O molecule by becoming H2SO4 (
2H+[SO4--] ) again, just as it did initially before any
current was supplied. Or, in the case of sodium sulfate ( NaSo4 or;
Na+[SO4 -2] ) the products that remain after electrolyzation
are the same products that began the reaction, only water disappears
(is consumed).
After considering the data contained in this paper I have
concluded that the reactions which occur in a primary (voltaic) cell
and the reactions that occur in an electrolysis cell are identical
except for the fact that in the primary cell the anode is oxidized
and decomposes and in the electrolysis cell (using electrodes which
are chemically inert to the action of the electrolyte) the oxygen
itself is oxidized. Here then, is the explanation of the seeming
"surplus" energy that we get from our electrolysis cell. Since the
reactions in both the battery and the cell are identical, then, by
artificially creating a potential difference between the inert
electrodes with the supplied current, we are causing the cell to
function as a battery with the oxidation/reduction reaction
proceeding in reverse. However, since no actual current passes
through the battery the supplied electricity is instead stored up in
the H2(g) that is released. So therefore you effectively double your
supplied energy by using that supplied energy to stimulate the same
set of reactions which result in the release of energy in a primary
cell.
That this is just a coincidental effect of the normal operation
of the electrolysis cell can be demonstrated by considering the
results that could be expected if the cathode was made of a material
that could itself be reduced by combining with the H+ ions, and the
anode of a material which could be oxidized by the SO4 -2 ions. If
that was the case the results might look like this;
H2SO4-----------------> H2M(s) + ZnSO4(s)
electrolysis
Each individual reaction would look like this;
Cathode: 2H+ and M(s)----------->H2M(s) -135kcal
Anode: Zn(s) + SO4 -2--------------->ZnSO4 +135kcal
In this case the process and the resulting products would still
follow Faraday's laws but there would probably be no opportunity to
extract further energy out of the by-products of this system because
the hydrogen and oxygen, which would otherwise be released, would now
both be bound into other molecules. Please note though that a
quantity of electricity still exits the cell at the anode which is
equal to the quantity which enters at the cathode and again, this is
as it must be to preserve chemical equilibrium within the
solution.
As another example consider the secondary cell, such as is used
for car batteries. In this type of battery there is no current
produced, the input current is merely stored as potential chemical
energy by causing a set of chemical reactions to proceed in one
direction and later released by allowing the same set of reactions to
reverse themselves. However if such a battery is fully charged and
more electricity is passed through it H2O will be electrolyzed. Why?
Because, after being fully charged, the chemical reactions which
charged it cease and so, at that time, a secondary cell resembles, on
the one hand, an electrolysis cell in that it's electrolyte will no
longer attack the electrodes and instead the same set of reactions
between the water, the electrolyte and the current takes place as
detailed above in an electrolysis cell and NOW the secondary cell,
which cannot normally produce electricity, is acting like a primary
cell because, given the fact that the above set of reactions are
taking place, it is producing an amount of electricity at the anode
which is equal to the amount of current that is entering at the
cathode by the same set of reactions, and again, only water is being
consumed. Therefore it must be the splitting of the water itself
which is generating the extra energy. This too follows accepted fact
because we have seen that the two electrons from the H2 portion of
the water molecule are first passed to the oxygen atom and then to
the anode in a primary cell.
My conclusion then is that this is not a matter of "it might
work" or this is "theoretically possible" it is very simply HOW it
works and has always worked, since the time of Volta and Faraday. All
energies being consumed and produced are fully accounted for and so
the requirements for the laws that I quoted at the beginning of this
paper are being met. And yet the net result is that you are getting
twice as much energy out of the cell as what you put into it.
The next area which I plan to consider is resistance between
the electrodes and the solution and within the solution itself. From
the above information it would seem that there are several ways in
which such resistance could be increased or decreased to meet the
needs of particular applications and some preliminary experimental
evidence from my own research seems to validate this. My next then
paper will deal with the resistance of electrolysis cells and how to
control their conductivity to achieve the desired resistance effect
in multiple "series" cells.
END
BIBLIOGRAPHY
(1) Chemistry
McGraw-Hill Company, inc. Copyright 1957
By Michell J. Sienko
Associate Professor of Chemistry
Cornell university
And
Robert A. Plane
Assistant Professor of Chemistry
Cornell university
(2) Experimental Researches in Electricity
The Great Books, Encyclopedia Brittanica, Copyright 1952
By Michael Faraday
Originally published in 1839
(3) Electricity One-Seven
Hayden Book Company, Copyright 1966
By Harry Mileaf, Editor-in-Chief
(4) College Physics
McGraw-Hill Book Company, Copyright 1959
By Robert L Weber, Marsh W. white and Kenneth V. Manning
All from the Pennsylvania State University