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CLOSED-LOOP ELECTROLYSER
Though there appear to be numerous interpretations of how the process of electrolysis occurs - some thoughtful and considered, others being clearly due to a lack of basic education and general ignorance - there seems to be no clear consensus as to exactly what is occurring. Dig a little and there is a wealth of questions yet to be answered. Of course, if you don’t dig deep enough (or at all) and are willing to simply accept that electrolysis happens, then these questions are never likely to trouble you.
I have based my new concept Closed-Loop Electrolyser design on my theories of the process. If my theories are somewhere in the ball park then I should see results… emphasis on ‘If’.
The idea behind my Closed-Loop Electrolyser is very simple, but of course as I have designed it around my perception of the electrolysis process, it will only work if my ideas are to a greater extent correct.
A little history:
I was always intrigued by floating plates. They work as hard as the electrodes connected directly to the power supply, but these floating plates simply sit within the electrolyte at a point whereby they see a potential difference of around 2 volts (or above) from any adjacent electrodes. We get oxygen from one side of these plates and hydrogen from the other. They simply offer a place for ions within the fluid to exchange charges, so they are simply a charge exchange medium.
So this got me thinking: How can I exploit floating plates.
I then took inspiration from Lord Kelvin’s Water Dropper Experiment, which opened my eyes to just how potent the charge separation in water can be, and how easy it is to create a relatively large charge differential.
I see the dissociation of the water molecules into its constituent parts of oxygen and hydrogen as bascially a three-step process:
Step 1: ionisation
Step 2: separation of the ionic species
Step 3: the reaction of the ionic species at the electrodes to evolve gases
I always felt sure that these three processes could be made to happen independently of each other and possibly by doing this the process as a whole could be made far more efficient.
Conventional electrolysers apply a voltage to electrodes, which initiates a current flow through the liquid medium due to the ionic species therein. This current would appear not only to promote further ionisation, but also delivers the appropriate ions to the electrodes for charge exchanging.
So, when we add an electrolyte to water we provide a vast supply of ions that will be pulled to the electrodes once a voltage is applied across them. This is two-way traffic, as cations will make their way toward the cathode and anions will head off to the anode. This inevitably causes collisions and near misses with each other and intervening water molecules. But what exactly is happening when ions and molecules collide or near miss? How do these ionic currents induce the water molecule to ionise? Well, these collisions and near misses generate energy in the form of an electric field, and it is this electric field that causes the water molecule to ionise. It does this by altering the energy state of the covalent bonding electrons within the molecule. And this was one of my Eureka moments. That is, discovering that fluctuating electric fields are what initiates ionisation.
Given that water continually self-ionises without any current being drawn through it, research has led me to believe that we don’t need a heavy current to induce water to ionise further. To my mind, any increase in molecular movement should increase ionisation, and as the water molecule is a bipolar molecule, this should not be that hard to achieve.
By using a pulsing electric field to induce the water molecule to ionise, there is no longer any requirement for heavy current for this process.
If now we apply another voltage source independent of the pulsing electric field to initiate and encourage separation of the generated ionic species, then we could in theory create a fluid environment that is relatively negative in one area and relatively positive in another area. We achieve ion charge separation within the liquid medium.
What I propose, is to influence this ion separation by applying a voltage to metal plates placed either side of the vessel containing the water, so these plates are not in contact with the water itself, but they still influence the ionic species within the water.
As it stands, this is of no use to us, as there is no ion exchange medium by which ions can give up or take on charges. Lots of ionic species, but no gas production.
This is where Lord Kelvin’s Water Dropper Experiment inspired me.
Now, if I introduce conductive metal strips, grids, wires or plates into the fluid where there are high proportions of opposite ionic species and form a closed loop, I provide a pathway for these different charges to exchange and hence evolve gas. But it all happens within the closed loop. No external current is being drawn through the liquid.
I said closed loop, well almost a closed loop, we actually leave a spark gap, a break in this circuit, between which sits an additional centre terminal.
I use a steady voltage (or pulsing, as long as the dc level is set above that of the voltage required to initiate electrolysis) on metal plates outside of the vessel containing water.
There are metal conductors sitting in the water in close proximity to (but obviously insulated from) the external plates. Conducting wire or tubes lead up from these conductors to a spark gap with a centre electrode.
I also have a coil of copper wire or tubing winding around the vessel. This copper coil is open-ended, with one end being the centre terminal between the spark gap.
So theory behind my Closed-Loop Electrolyser goes like this:
A pulsed or steady dc voltage on external plates encourages any ions in the water to separate and congregate in opposite areas of the vessel close to metal conductors within the solution. At some point enough charges will have congregated to jump the spark gap. When this happens the charges are exchanged on the internal conductors and gas is evolved. Also, when the spark gap is activated, the centre electrode sees a high voltage that creates an electric field whereby it actually induces more water molecules to ionise.
This way the process is self-sustaining as long as the voltage on the external plates is maintained. The beauty of this Closed-Loop Electrolyser is that heavy current can flow within the closed circuit, but hardly any external power is used to achieve this.
Faraday’s Laws are still obeyed in full in that the current flowing through the closed circuit is proportional to the amount of gases evolved, but the beauty of my set up is that current is not being taken from the voltage supply source.
Power = voltage x current.
By using voltage alone to induce the water molecule to ionise we require next to no power.
By using voltage alone to encourage separation of the induced ionic species, we require next to no power.
To evolve the gases we use a spark gap, which allows the voltage to build, but as it is an open circuit no current flows. Once a predetermined voltage is reached the air between the spark gap will ionise allowing current to flow and charges from the residing cations and anions to be exchanged at the electrodes. We get gas evolved.
This then constitutes a new concept in electrolyser design, whereby much greater efficiencies can be obtained when compared to conventional electrolysers.
A depiction of the proof of concept model is attached.
I should add that at this stage, this is unproven theory. My proof of concept model is under development, though I envisage things will not be straight-forward nor initial experiments go as planned. I'm not being intentionally over-pessimistic here, rather just preparing myself for the almost inevitable initial set-backs.
Farrah
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