Why is this water turning black during electrolysis?

[themerge]

Good day,

I am here because I have begun a new hobby and it is my hope to better understand what it is I am doing and seeing. Luckily I have the mental capacity to process much of what I read, but sadly I am vastly under-educated. My new project involves electrolysis and for reasons I don't understand the water can turn black (see images)

To begin I am ionizing water with a membrane (chamois) in the center of the tank. This works effectively as I can see the difference in the water as oxygen bonds are broken and hydrogen bonds are broken. I run this ionization process for about 24 hours before I drop charging plates in the negatively charged side for a couple of hours and then the positive side for a couple of hours. I then let the particles in the water settle for 24 hours. The negative side will remain clear with debris on top of the water and much debris gathered at the bottom of the tank. I then drain both sides equally, clean the tank and repeat the process.

The last stage involves me recombining both the positively charged and negatively charged waters and once again throwing a 2 hour charge on the water. This is where I run into my problems. Everything appears to be ok and all of my sample waters turned out fine with the particles separating and dropping to the bottom, but when I do the bulk water my water always turns black. and will not separate with electrolysis.

My only solution thus far has been to run a fish tank pump for a duration of time to filter the water enough that I can use a carbon filter to finish the job. In the end I end up with negatively charged water and didn't have to pay thousands of dollars for a machine on the market. The image with the major mineral build up on the left is only visible because of the 2500 lumen light. The other image is what I see normally.

I forgot to mention this is spring water with no electrolyte added.

 

[anorlunda]

Welcome to PF.

We don't deal with questions in the New Member Introduction forum, so I moved this thread to a better place. I think that better place is chemistry.

 

[TeethWhitener]

The black material is probably an oxide/hydroxide compound of whatever metal you're using as your electrodes.

In the end I end up with negatively charged water

No you don't. That's not how electrolysis works.

I forgot to mention this is spring water with no electrolyte added.

Spring water has plenty of electrolytes in it already.

 

[BillTre]

The black material is probably an oxide/hydroxide compound of whatever metal you're using as your electrodes.

Are your electrode getting etched or corroded?
This would be expected if material in the water were being derived from the electrodes.

 

[Borek]

To begin I am ionizing water with a membrane (chamois) in the center of the tank.

Whatever the "membrane" does it is not "ionizing" water. I am afraid it sounds like some mumbo-jumbo pseudoscience.

Ionization basically means converting something into ions - either by removing or adding electrons, or by splitting larger molecules into charged parts. Water molecules get split in a process called "autoionization" - so some ions are present always, even in the purest water samples (so called ultra pure water, or 18 MΩ water - after its specific resistance).

This works effectively as I can see the difference in the water as oxygen bonds are broken and hydrogen bonds are broken.

How do you "see" the difference, and how do you know the bonds are broken? Molecules are way too small to be observed by a naked eye, so at best you observe some secondary effect and interpret it as bonds being broken. But how do you know your interpretation is a correct one?

 

[Klystron]

Chamois? Deer skin? Animal skin introduces biological substances into your experiment not to mention providing sustenance for bacteria and other organisms depending on conditions. Artificial membranes such as those used in reverse osmosis water filters avoid organic contamination, are common and likely less expensive than animal skin.

Also suggest obtaining pH tester either chemical or electric. PH is a measure of acidity or alkalinity. How is pH relevant to your experiment?

 

[themerge]

Are your electrode getting etched or corroded?
This would be expected if material in the water were being derived from the electrodes.

How is it that 1 amp can strip that much 316L stainless from from my .083 plates. Also when I am done processing the water I freeze samples where the top of the ice cube is clear like gas and the bottom is cloudy like crystals formed around particles in the water.

 

[themerge]

Chamois? Deer skin? Animal skin introduces biological substances into your experiment not to mention providing sustenance for bacteria and other organisms depending on conditions. Artificial membranes such as those used in reverse osmosis water filters avoid organic contamination, are common and likely less expensive than animal skin.

Also suggest obtaining pH tester either chemical or electric. PH is a measure of acidity or alkalinity. How is pH relevant to your experiment?

I failed to mention the Chamois is artificial and a third the price.

 

[BillTre]

How is it that 1 amp can strip that much 316L stainless from from my .083 plates. Also when I am done processing the water I freeze samples where the top of the ice cube is clear like gas and the bottom is cloudy like crystals formed around particles in the water.

An amp is 6.242×10¹⁸ charges moving in a second.
A mole has 6.02x10²³ particles (ions), so that's about a 1/100,000 of a mole per second assuming single charged ions.
How many seconds were you running this for, in total?

 

[themerge]

Chamois? Deer skin? Animal skin introduces biological substances into your experiment not to mention providing sustenance for bacteria and other organisms depending on conditions. Artificial membranes such as those used in reverse osmosis water filters avoid organic contamination, are common and likely less expensive than animal skin.

Also suggest obtaining pH tester either chemical or electric. PH is a measure of acidity or alkalinity. How is pH relevant to your experiment?

Well I am going for a more acidic water. PH is also indicative of charge. Lower PH has more electrons where

An amp is 6.242×10¹⁸ charges moving in a second.
A mole has 6.02x10²³ particles (ions), so that's about a 1/100,000 of a mole per second assuming single charged ions.
How many seconds were you running this for, in total?

Well my two larger plates 9x10 inches run for at least 24 hours and then I take 4 6x6 plates and run them for two hours on each side. By the way I just ran for 42 hours with tap water and I didn't get a bit of build up on the bottom of my tank other than maybe some chlorine.

 

[themerge]

Chamois? Deer skin? Animal skin introduces biological substances into your experiment not to mention providing sustenance for bacteria and other organisms depending on conditions. Artificial membranes such as those used in reverse osmosis water filters avoid organic contamination, are common and likely less expensive than animal skin.

Also suggest obtaining pH tester either chemical or electric. PH is a measure of acidity or alkalinity. How is pH relevant to your experiment?

"Non-neutral pH readings result from dissolving acids or bases in water. Using the negative logarithm to generate positive integers, high concentrations of hydrogen ions yield a low pH number, whereas low levels of hydrogen ions result in a high pH. "

 

[themerge]

Whatever the "membrane" does it is not "ionizing" water. I am afraid it sounds like some mumbo-jumbo pseudoscience.
See the picture below Hydrogen ionization is happening on the cathode side. Not mumbo-jumbo, half of physics is built on unproven theories.

Ionization basically means converting something into ions - either by removing or adding electrons, or by splitting larger molecules into charged parts. Water molecules get split in a process called "autoionization" - so some ions are present always, even in the purest water samples (so called ultra pure water, or 18 MΩ water - after its specific resistance).
How do you "see" the difference, and how do you know the bonds are broken? Molecules are way too small to be observed by a naked eye, so at best you observe some secondary effect and interpret it as bonds being broken. But how do you know your interpretation is a correct one?

The part of the tank of the left was the cathode side and the right was the anode side. It is self evident that the cathode side is breaking bonds with whatever minerals are in the water.

 

[Borek]

PH is also indicative of charge. Lower PH has more electrons where

No, that's not how it works. Doesn't matter what is pH of the solution, it is always perfectly neutral electrically. It may contain more ions (so higher concentration of charged particles), but every ion is accompanied by a counterion and the resulting total charge is zero.

Number of electrons has nothing to do with that.

I didn't get a bit of build up on the bottom of my tank other than maybe some chlorine.

Chlorine is a gas, so if anything, it will bubble out of the solution, not precipitate.

It is self evident that the cathode side is breaking bonds with whatever minerals are in the water.

As I said earlier - it is evident that something is different on both sides, but I would be very careful with assigning the change to "breaking bonds". Breaking bonds has a rather specific meaning - it typically means splitting the bond inside a molecule, converting one substance into another, simpler one (which can, and often will, react further). It is self evident water in both parts of the tank has different amount of substances dissolved, but your conclusion about "broken bonds" is way far too fetching.

If I can suggest something - try to find some introductory text (like High School textbook) and read it. At the moment you have a lot of enthusiasm, but you tend to misuse nomenclature and you fill the gaps in your understanding with guesses. In my experience that's a disaster waiting to happen, sooner or later we will have enough of trying to guess what you really mean and you will think we are purposely not helpful.

 

[sysprog]

I failed to mention the Chamois is artificial and a third the price.

Well, it still probably contains carbon (lengthy polycyclic aromatic hydrocarbon chains), and is probably the material contributor by which was disclarified the color of the precipitates of your electrolytic process.

 

[TeethWhitener]

How is it that 1 amp can strip that much 316L stainless from from my .083 plates.

You didn't answer @BillTre 's question. Does it look like material is being lost from the stainless steel plates?

then I take 4 6x6 plates and run them for two hours on each side.

What does "on each side" mean? Don't you immerse the whole electrode in water? If it's steel, the entire electrode will be at the same potential, i.e., it won't have a preferential "side."

Well, it still probably contains carbon (lengthy polycyclic aromatic hydrocarbon chains),

I seriously doubt that artificial chamois is made of PAH's. It's a polymer, not carbon fiber.

If I can suggest something - try to find some introductory text (like High School textbook) and read it.

I second this. You're providing irrelevant information (e.g., the price of an artificial chamois) and leaving out important information (e.g., voltage and pH), so it's difficult to help you figure out what's going on.

 

[gleem]

It would also be of help to know the purpose of this project and the rationale for your choice of materials and the procedures that are used.

 

[willem2]

How is it that 1 amp can strip that much 316L stainless from from my .083 plates. Also when I am done processing the water I freeze samples where the top of the ice cube is clear like gas and the bottom is cloudy like crystals formed around particles in the water.

You have probably produced hazardous materials. Stainless steel contains chromium, and at the anode it can get oxidized to Cr(VI). It seems that stainless steel is still often used for electrodes, but I think only with a suitable electrolyte, so the electrons from the electrolyte will be removed, and not from the iron and the chromium.

 

[Shekhar shah]

According to him turning of watercolour to pale yellow after electrolysis test is the purest form of water, turning off water to red colour means it contains Iron Rust, to black means, it contains heavy metals, blackish green means it contains copper rust, lead.

 

[TeethWhitener]

According to him turning of watercolour to pale yellow after electrolysis test is the purest form of water,

Well, "him" is wrong. Pure water is clear and colorless. If it's yellow, it's not pure.

 

[hilbert2]

If I remember correctly, electrolyzing a 20 mass-% sodium chloride solution with both cathode and anode made of stainless steel, and with 3 amp current, caused the water to turn black really quickly from the anode getting oxidized. It didn't take even 30 minutes for the anode to completely corrode to black oxide/hydroxide sediment that sunk on the bottom of the cell.

The cathode in a cell with semipermeable membrane separating the cathode and anode compartments can also corrode and dissolve if it's made of aluminum or something else that reacts with the hydroxide ions produced in the electrolysis.

"Positively and negatively charged waters" is an impossibility. For instance, dissociating even 1% of the electrons from a liter of water and moving them to 10 meter distance would probably consume more energy than the whole world's annual electricity consumption.