Is electrolyte chemical consumed during alkaline water electrolysis?

In summary, in alkaline water electrolysis you add Potassium hydroxide, or Sodium hydroxide to the water you want to turn into hydrogen and oksygen. However, the Potassium hydroxide, or Sodium hydroxide is consumed during the electrolysis process and must be replaced. Alternatively, you can keep adding water to the alkaline water electrolyser as it turns into hydrogen and oxygen.
  • #1
Stormer
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In alkaline water electrolysis you add Potassium hydroxide, or Sodium hydroxide to the water you want to turn into hydrogen and oksygen. But is the Potassium hydroxide, or Sodium hydroxide consumed during electrolysis and needs to be replaced? Or do you just have to keep adding water as it is turned into hydrogen and oxygen?
 
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  • #2
I expect for a DC current cell, collecting the gasses separately, the potassium metal or sodium metal would be electro-plated onto the electrode. That may depend on the cell voltage.
For an an AC current cell, collecting mixed gasses, the metals would not be consumed as they are cyclically plated onto, and then stripped off the electrodes.
 
  • #3
Baluncore said:
potassium metal or sodium metal would be electro-plated onto the electrode
Are you certain? We're talking about an aqueous system
 
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  • #4
Baluncore said:
I expect
Bystander said:
Are you certain?
No.
But reaction of the metal and water may be prevented by the voltage gradient at the polarised electrode surface.
Do you have a better answer?
 
  • #6
Baluncore said:
I expect for a DC current cell, collecting the gasses separately, the potassium metal or sodium metal would be electro-plated onto the electrode. That may depend on the cell voltage.
For an an AC current cell, collecting mixed gasses, the metals would not be consumed as they are cyclically plated onto, and then stripped off the electrodes.
In that case alkaline water electrolysis would come out pretty bad compared to PEM electrolysis even with the higher cost of the materials in the PEM membranes.
Or maybe you can switch a DC alkaline elektrolyser polarity at regular intervals making a kind of low frequency switched AC and at the same time switching a valve to keep the oxygen and hydrogen in their separate output pipes? Just to avoid the electroplating of the electrodes, and the consumption of the electrolyte chemistry.
 
Last edited:
  • #7
Stormer said:
Just to avoid the electroplating of the electrodes, and the consumption of the electrolyte chemistry.
I think it is only necessary to momentarily remove the potential to recover the plated material. That suggests a pulsed, or a full-wave rectified AC supply will continuously recycle the metal hydroxide while keeping the gasses separate.
 

Related to Is electrolyte chemical consumed during alkaline water electrolysis?

1. What is electrolyte chemical?

Electrolyte chemical is a substance that conducts electricity when dissolved in water. It contains ions that are responsible for carrying electric charge.

2. How is electrolyte chemical consumed during alkaline water electrolysis?

In alkaline water electrolysis, an electric current is passed through water containing electrolyte chemicals, such as sodium or potassium hydroxide. This causes the water molecules to split into hydrogen and oxygen gas. The electrolyte chemicals are consumed in this process as they help facilitate the movement of ions and the overall electrolysis reaction.

3. Is it safe to consume electrolyte chemicals in alkaline water?

Yes, it is safe to consume electrolyte chemicals in alkaline water as long as they are present in small amounts. The electrolyte chemicals are typically used in very low concentrations and do not pose any health risks. However, it is important to follow recommended guidelines for alkaline water consumption and not to exceed the recommended daily intake.

4. Can electrolyte chemical consumption have any negative effects on the body?

In small amounts, electrolyte chemical consumption does not have any negative effects on the body. However, consuming excessive amounts of electrolyte chemicals can lead to an imbalance in the body's electrolyte levels, which can cause symptoms such as nausea, vomiting, and muscle weakness. It is important to follow recommended guidelines for alkaline water consumption and not to exceed the recommended daily intake.

5. Is it necessary to add electrolyte chemicals to water for alkaline water electrolysis?

Yes, electrolyte chemicals are necessary for alkaline water electrolysis as they help facilitate the movement of ions and the overall electrolysis reaction. Without the presence of electrolyte chemicals, the water molecules would not be able to split into hydrogen and oxygen gas. However, it is important to use the correct amount of electrolyte chemicals and not to exceed recommended guidelines for alkaline water consumption.

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