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Stainless Steel Alternatives.


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I am working on a collage project for making hydrogen gas. I use an electrolysis process to generate Hydrogen gas from water. I was wondering that are there any alternatives of Stainless Steel Plates for this procedure? I use tin, it work well but failed to generate enough gas.

 

i'm not sure if any particular metal makes a better electrode as far as amount of gas. :confused: however, increasing the surface area of the electrode(s) and/or increasing the voltage ought to produce more gases in a shorter time. ideal electrodes would be platinum or graphite as they don't foul the electrolyte.

 

ps what are you using for the electrolyte?

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A better conducter would help as a material, but stainless steel doesn't oxydise easily and is a (relatively) good conductor. Try a jagged shape for the electrodes.

 

Like this:

 

/\/\/\/\/\

\/\/\/\/\/

 

i have used stainless before & found it to break down quite quickly & foul the electrolyte. :naughty: it is not a matter of a better conductor, as silver is the best conductor and breaks down so well at the anode that it is used in electroplating. :doh: "shape" is relevant insofar as i mentioned, i.e. gaining an increase in surface area. :turtle:

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Titanium, Silver, Platinum and Graphite are good alternatives and some of them are even better than Stainless Steel but as I already mention that its a collage project and I don't have too much to spend.

I was considering Copper but I am not sure that it would react with Oxygen. Is it possible that some how the following equation reversed by electrolysis:

2CuO + 2H2 ---------> 2Cu + 2H2O

Like this

2Cu + 2H2O ---------> 2CuO + 2H2

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Titanium, Silver, Platinum and Graphite are good alternatives and some of them are even better than Stainless Steel but as I already mention that its a collage project and I don't have too much to spend.

I was considering Copper but I am not sure that it would react with Oxygen. Is it possible that some how the following equation reversed by electrolysis:

2CuO + 2H2 ---------> 2Cu + 2H2O

Like this

2Cu + 2H2O ---------> 2CuO + 2H2

 

Yes, if you use a copper anode then it will oxidize rather than the OH- ion. The solid copper anode is dissolved giving what is commonly called anode sludge. I recall this happened to turtle in an experiment outlined in a previous thread where he used a copper electrode.

 

Once you have copper ions in solution they will be reduced at the cathode rather than hydrogen because Cu2+ is lower than H+ in the electrochemical series. So, you get solid copper deposited on the cathode rather than hydrogen gas produced even if the cathode is platinum or carbon.

 

I think your cheapest and best bet is to use stainless steal. I would personally go to walmart and find a cheap kitchen utensil like a spatula or perhaps a wire mesh strainer.

 

More important, I think, is your choice of electrolyte and voltage. What electrolyte are you using and what is your power source?

 

~modest

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Titanium, Silver, Platinum and Graphite are good alternatives and some of them are even better than Stainless Steel but as I already mention that its a collage project and I don't have too much to spend.

snip...

 

you could use pencil "leads" which are graphite. using a bunch/bundle of them you can increase your surface area. no more expensive than...well, pencils. :idea:

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i have used stainless before & found it to break down quite quickly & foul the electrolyte. :naughty:

 

I missed this post before commenting earlier:

 

I think your cheapest and best bet is to use stainless steal.

 

otherwise I would have agreed that stainless steel can indeed corrode very quickly most especially if the electrolyte has chlorine. :agree:

 

It all depends on the electrolyte. I'm pretty sure with NaOH, which works well for H2 and O2 production, both 304 and 316 stainless steel (the two most common for cooking and eating utensils) would be very resistant to corrosion.

 

you could use pencil "leads" which are graphite. using a bunch/bundle of them you can increase your surface area. no more expensive than...well, pencils. :idea:

 

That sounds like a really good idea!

 

A person could use a stripboard to hold a row of them, then dip the stripboard with the wire lead in wax to insulate all but the graphite.

 

~modest

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Yes, if you use a copper anode then it will oxidize rather than the OH- ion. The solid copper anode is dissolved giving what is commonly called anode sludge. I recall this happened to turtle in an experiment outlined in a previous thread where he used a copper electrode.

 

Once you have copper ions in solution they will be reduced at the cathode rather than hydrogen because Cu2+ is lower than H+ in the electrochemical series. So, you get solid copper deposited on the cathode rather than hydrogen gas produced even if the cathode is platinum or carbon.

 

I think your cheapest and best bet is to use stainless steal. I would personally go to walmart and find a cheap kitchen utensil like a spatula or perhaps a wire mesh strainer.

 

More important, I think, is your choice of electrolyte and voltage. What electrolyte are you using and what is your power source?

 

I am using water as electrolyte and car battery to power it.

 

you could use pencil "leads" which are graphite. using a bunch/bundle of them you can increase your surface area. no more expensive than...well, pencils.

 

Actually my project would be planted on car therefore I need something which do not break so easily, Lead is, although, a good idea if we a conducting in a room but for a moving object on a rough surface, it won't work that fine.

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We are basically working for cheep fuel source and healthy to environment. Some companies already using HHO gas to fuel the vehicle. But what we are planning to do is to create pure Hydrogen gas from water as a fuel. Theoretically, it works great on paper but it was not a huge success in reality. I am unable to generate as much gas as required.

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I am using water as electrolyte and car battery to power it.

 

Actually my project would be planted on car therefore I need something which do not break so easily,

What is keeping the battery charged, besides the engine via the alternator? Are you planning to use it for regenerative breaking? You should look into high efficiency fuel cells, instead of keeping the ordinary battery and adding a separate unit for electrolysis.

 

We are basically working for cheep fuel source and healthy to environment. Some companies already using HHO gas to fuel the vehicle. But what we are planning to do is to create pure Hydrogen gas from water as a fuel.
Hydrogen is definitely an eco-friendly fuel, but it also depends on the source of electric energy you use to drive the electrolysis and also it isn't easy to store in large quantities.

 

Theoretically, it works great on paper but it was not a huge success in reality. I am unable to generate as much gas as required.
Not counting losses, the quantity of fuel from each cell is at the most given by Faraday's law and the minimum voltage across each cell by chemical and thermodynamic matters plus energy losses.

 

The caloric content of the quantity of fuel you get is at the very most equal to the electric energy employed. Beware of hoping to use the engine power to recover as much fuel as the engine consumes, as well as the power propelling the vehicle etc.

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I am using water as electrolyte and car battery to power it.

 

You really need to add an electrolyte like a small amount of NaOH to the water. As wiki says:

 

Electrolysis of pure water requires excess energy in the form of overpotential to overcome various activation barriers. Without the excess energy the electrolysis of pure water occurs very slowly or not at all. This is in part due to the limited self-ionization of water. Pure water has an electrical conductivity about one millionth that of seawater. Many electrolytic cells may also lack the requisite electrocatalysts. The efficacy of electrolysis is increased through the addition of an electrolyte (such as a salt, an acid or a base) and the use of electrocatalysts.

 

 

and another site:

Pure water is not used in electrolysis — pure water inhibits electrical conduction. To allow the electrical current to pass through the water, substances must be added to it. These substances dissolve to form something called electrolytes.

 

 

Electrolysis is most efficient at something like 3 or 4 volts (I don't recall exactly at the moment). As you increase the voltage, you end up losing more energy to heat. It would be a good idea to step down the voltage of a car battery from 12 volts to something less

 

~modest

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I was kinda supposing he wasn't using distilled water. Even tap water has some electrolytes in it. Adding a tiny amount of salt or something to distilled water makes it appreciably conductive, but no doubt it's a good idea to add salt into his cells.

 

Electrolysis is most efficient at something like 3 or 4 volts (I don't recall exactly at the moment). As you increase the voltage, you end up losing more energy to heat. It would be a good idea to step down the voltage of a car battery from 12 volts to something less
The easiest thing is to have 3 or 4 cells in series.
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I was kinda supposing he wasn't using distilled water. Even tap water has some electrolytes in it. Adding a tiny amount of salt or something to distilled water makes it appreciably conductive, but no doubt it's a good idea to add salt into his cells.

 

I agree that tap water is conductive, but not efficiently so and I wouldn't trust the gas being produced to be consistently hydrogen and oxygen.

 

I'd avoid table salt, NaCl, because it will produce chlorine gas rather than hydrogen (the chlorine ion has a larger standard electrode potential than hydrogen). Other salts, I agree, will work very well. Sulfate salts, in particular, work well. Potassium sulfate, for example. Sulfuric acid would also work fine.

 

The easiest thing is to have 3 or 4 cells in series.

 

:agree:

 

~modest

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Yes, I should agree.

 

Wajahat, creating hydrogen and oxygen, in the form of HHO or in its diatomic state, cannot increase the efficiency of your vehicle's work to fuel ratio. Even if your electrolysis unit were perfectly efficient, dumping gas created into the engine could do no better at running the engine than the fuel needed to create the HHO would have done being added to the engine without the unit.

 

If you're using the gas for something else then I say good luck and don't singe the eyebrows.

 

~modest

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