The Efficiency of Hydrogen Production Through Electrolysis By Noah Wade, Ekaterina Vasileva, Michael

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• The Efficiency of Hydrogen Production Through
  Electrolysis By Noah Wade, Ekaterina Vasileva,
  Michael Sheng and John-Nicholas Furst

Results
The data suggest that no accurate trend line can
be generated on based collected data. The R2
values for Excel generated trend lines were not
within an accepted range to make scientific
conclusions see Chart 1. R2 values for trend
lines need to be above 0.5 for any scientific
conclusion to be made based on the data. In this
test the highest values was measured at 0.34. In
general however, the higher voltage test did have
higher weight difference the lower test but both
10 volts and 15 volts test produced more hydrogen
than the 20-volt test suggesting the differences
in production may just be a natural deviation or
the there is not correlation between voltage and
hydrogen produced and that there is simply always
going to some deviation in the amount produced.
Introduction
Methods
In order to test how changing the voltage of the
electric current passing through the electrolysis
reaction affects the amount of hydrogen produced,
a basic electrolysis reaction was set up. This
included an anode and a cathode each being placed
in water and then connected with electrical wires
to a variable power supply to control the voltage
in each test. During all tests a standard 25,000
J were used in order to keep voltage as the
single variable. To do so calculations were made
using scientific equations, see equation 1. Then
five voltages, 10, 15, 20, 25, and 30 volts, were
each tested three times with their corresponding
times for the calculations see table 1. During
each test a collection cup was placed above the
cathode in order to collect the hydrogen being
created that was bubbling to the surface. The cup
was massed before and after the experiment in
order to measure how much hydrogen was produced.
Modern fuel cells have been created that can
produce almost as much energy as a standard
engine. These fuel cells are now being put into
cars that produce no harmful pollutants. Right
now the major limitation on mass production of
these cars is the lack of hydrogen and problems
associated with storage and transport of such a
reactive element. Hydrogen's properties are such
that it will react with almost anything making it
very difficult to store in a safe environment
were it there is no risk of explosion.
Electrolysis is a method of producing hydrogen
that could be used for production. During
electrolysis an electric current is run through
water, the energy provided by the electric
current splits the water into hydrogen gas and
oxygen. Electrolysis can also be preformed on any
scale, in larger industrial power plants or in a
small science class room. This study looks at if
changing the voltage of the electric current used
to power the reaction will help to increase the
overall efficiency, by keeping the same amount of
energy used to power the reaction while changing
the voltage.
Chart 1.
Equation 1.
Picture 1. Set up of electrolysis reaction,
without collection cups.
Chart 1. Graph of Hydrogen Weight Displacement
vs. Volts Used with Excel generated trend lines
based on collected experimental data.
Equation 1. Shows how by using the definition of
Volts and Watts a correlation was mathematically
determined between Volts and Seconds if Joules
and Amperes were kept constant. This allowed each
test to have the same overall amount of energy
while collecting data.
Discussion
The data collected in this experiment proved
inconclusive. An area of error in this experiment
included in precise measurement of the mass of
the cup before and after the experiment. The mass
of the cup was taken using an electric scale the
measured to three decimal places, given the small
difference in the collected data this scale
didnt provide precise enough measurements for
definitive conclusions to be made. In addition
the temperature of the water was not monitored
over the duration of the test leaving so possible
uncontrolled variable to influence data. These
errors in scientific measurement provided
uncertainty in the data that to led multiple
conclusions. Higher voltages did produce mover
hydrogen in most cases but differences were so
small that natural chance and experimental error
may have produce these results. There were also
examples of lower voltages producing more
hydrogen then higher voltages. For a definitive
conclusion to be reached further testing with
improved scientific procedures would need to be
preformed in order to collect more data.
Suggestions for further testing include using a
Hoffman electrolysis set up that provides a more
scientific experimental set up and testing a
wider range of voltages to investigate trends on
a larger scale.
Table 1.
Table 1. Pretest calculations based volts watts
/ amperes and watts joule / second to calculate
time need in order to maintain a constant amount
of energy for all test.
Last updated Feb 18, 2007