Remove Rust Easily and Effectively With Salt and Electricity.

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Introduction: Remove Rust Easily and Effectively With Salt and Electricity.

About: Hi my name is Zack i'm 15 years old and i like to make robots, experiment with electronics, play with science, photography and have fun doing it.

Hello everyone, want to find out how to rid rust on your tools for cheap, easily and safely?

This is a inexpensive, safe and interesting science experiment you should try on your tools to rid of rust Instead of using acid, Grinding or heavy wire brushing and loosing any steel. By using electrolysis to remove the rust from your dirty tools or just about anything rusty that you can submerge in a container of salt water that isn't brass, aluminum, copper or exotic metals and alloys, you will lose almost all rust and not lose any of your metal in the process.

Step 1: What Is Electrolysis?

Electrolysis is a way of turning direct current (DC power) into a chemical reaction to produce hydrogen and oxygen and during this reaction the anode is forming large quantities of rust and slowly eats away at the anode while the cathode is doing the opposite and is bubbling hydrogen constantly and during that it cleans away rust which is exactly what we are going to do.

Step 2: Setup.

Choosing the right container and filling it with saline solution (salt water)

Fill your desired container with water and add salt( the more salt the faster the process and a saturated solution will work best. Make sure that your container is not going to be used again due to staining the container with dirty rust after use. If you use salt water from the ocean like i am then there is no need for adding salt.

Wiring it all up.

Take a paper clip and unwind it until it has a hook shape that fits the neck of the bottle and attach a wire or alligator clip to to the paperclip like the picture above and make sure that the paperclip is in the solution except for the alligator clip because otherwise your alligator clip will get rusty.Add another alligator clip but this time to the object you want to rid of its rust and bath it completely in the solution and its fine if your alligator clip on the cathode is in the solution because it wont grow rust but always make sure that you dry your alligator clips after use.

Note

Do not let the two wires touch as it would cause a short circuit which stops the experiment and if you use a lithium battery to power the experiment and the two wires touch then it could literally make the battery explode but your safe without a lithium battery. Also its a good idea to do this experiment outside because hydrogen and chlorine gas is produced and hydrogen can ignite very easily and chlorine is very toxic but i did mine inside because mine was not producing that much chlorine in the process and if you don't want to have the problem with chlorine gas, then instead of using salt as your electrolyte, just use Washing Soda as your electrolyte.
And do not use stainless steel tools as it has a poisonous substance it produces.

Step 3: Waiting for Magic to Happen.

Hook up your power supply (i used 5v from an arduino) and your cathode should start bubbling like the photo i have shown while the Anode (paper clip) grows rusty sludge and makes the water turn dirty as you can see by the animated GIF above. I waited for as long as 30 minutes for the process to be done and washed the screw driver thoroughly with steel wool and paper towl to get the muck off and your done, your tool has now got no rust but if your tool does have a little bit of rust on it still then just put it back into the solution again for a little longer.

Step 4: What About Different Types of Tools?

What about different types of tools because other tools might be harder to wash with steel wool and i'm going to relate to that with a drill bit and a pair of pliers.

Pliers.

The pliers was easily washed with steel wool after electrolysis and got rid of all rust but because rust eats at metal, it does leave the metal with mild marks and if it were heavy rust on the pliers it would have left bigger dents trailing across the metal like the screw driver and can be smoothed with sandpaper.

Drill bit.

The drill bit was washed forcefully and although it did clean the outside layer of thread, it did not clean the inside of the thread because it is hard to get the rust out of the inside especially when it is sharp and you don't want to cut yourself so i found a solution to this problem.

First. Use steel wool to clean as much as you can,

Second. Get a spoon of baking soda and mix it with a few drops of water till it becomes a thick paste and rub it all over the drill bit where you need to clean just like the picture above

Third. Place the drill bit in your sink (i'm using a container in a sink so i can put more baking soda in)

Fourth. Get around 2 ounces of vinegar and pour it in and watch the reaction take place like the animated GIF above.

Fifth. Use cotton swabs to clean out the inside of the drill bit until gunk stops going on your cotton swab.

Step 5: Results.

The results are effective as you can see. Try this for yourself and you'll be amazed by the power of electrolysis.

Thanks for looking at this instructable and please comment, favorite, and follow.

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    37 Comments

    Will this work on cast iron? I'm not having much luck with vinegar and steel wool.

    2 replies

    yes it should work but maybe you could use baking soda in the electrolysis

    Instead of the salt to make it a bit more safe and better. I found a video of someone cleaning cast iron here: https://m.youtube.com/watch?v=0XlsNucmbiE

    Please Use Baking Soda instead of salt water. While it is a good conductor electrolysis of salt water produces concentrated and gaseous Chlorine and Hydrogen. The former is toxic and the later is explosive. Baking soda works just as well.

    3 replies

    This is incorrect. Hydrogen yes, chlorine no. See my previous comment.

    This is old, but deserves a reply... You are simply wrong. If you use chlorides in the electrolyte mix, you will generate Cl2 gas at the anode. Just google salt-water electrolysis products if you don't believe. In fact, you can buy "chlorinators" that use this process to chlorinate your home swimming pool.

    With the small project shown here, the chlorine doesn't really present appreciable risk since the small volumes of gasses produced are easily dissipated. Nonetheless, washing soda is much better electrolyte.

    Your concerns about damaging the treated article are valid if you are talking about collector-quality restorations of rusty articles. In those cases the lowest possible voltage is generally used, allowing as much iron as possible to "reconvert" back to the original surface. Higher voltages will, in essence, blast off the material that could otherwise have been reconverted.

    If you are't doing museum-quality conservation work, however, the higher voltages do work faster, and while you lose that small amount of material that wasn't reconverted, none of the base metal is lost, and that's what most of us are concerned about. Folks who restore old equipment use the higher voltages as standard practice.


    This is incorrect. Hydrogen yes, chlorine no. See my previous comment.

    Great Instructable. Glad you specified Cathode and Anode.

    The way I used to remember which was which ...

    Cats Paws an Egg Cat-Pos An-Neg

    meow

    Great Instructable. Glad you specified Cathode and Anode.

    The way I used to remember which was which ...

    Cats Paws an Egg Cat-Pos An-Neg

    meow

    I use washing soda instead of salt, works really well. Also, in my experience, the voltage is key for electrolysis (FYI to commenters). For example, I have an old telephone system power supply that I use, it's 24v and capable of (guessing) 6 or 8 amps, but it uses little current.. probably an amp at most. The current draw will depend on the solution, amount of rust, etc. For washing soda I use 1tbsp per gallon, any more is a waste (won't help the process), to help it along I use several electrodes to collect the rust, paint, etc that comes off the part I'm cleaning. A 5 gallon bucket with several rods around the outer walls of the bucket connected with some solid copper wire, 5 tbsp of washing soda and a good DC power supply works like magic :-). thanks for the instructable though, I like it!

    1 reply

    For cleaning, overvoltage of fine, any other kind of reaction will get you all kinds of oxides and other nasty stuff. If you want a fast safe reaction, then you want concentrated salts, low voltage, and high amperage. If you do it right, the solution will even heat itself further speeding things up. THe amperage is what is doing all the work. higher voltage does = higher amperage, but it also = less control over the reaction.

    This instructable is not a good way to clean rust. Doing it this way will damage your tools. Vinegar is ok as an electrolyte itself adding sodium to it will electroplate you tool with sodium metal which will form sodium oxide a white tarnish. Doing it with salt will drive hydrogen into your tools metal. The hydrogen then interacts with oxygen leftover from when the tool was made and can cause cracking and embrittlement. Repeated exposure to hydrogen can cause the tool to fail catastrophically. The proper way to remove rust is to do it with between 0.85 volts and 1.1 volts. Any more and you will start breaking down the water in large quantities. You can further suppress the issue by adding only vinegar (acetic acid). Most metal salts of acetic acid are water soluble so there will be no corrosion. This will dissolve and attack the rust a long time before damaging the metal. However, overvolting vinegar will damage the metal the same way. Using sodium bicarbonate as the electrolyte will give you carbonate based corrosion and will bubble off carbon dioxide at the electrodes. Their of those byproducts are useful. If you want to clean a lot of rust quickly, then using a higher concentration of acetic acid will speed it up, and adding hydrogen peroxide to the mix will activate the vinegar into an acetate anion (which is the part that actually does the work. If this is used to clean tools (especially if they are copper coated), then you need to mix the leftover gunk with baking soda before disposing. Copper acetate and ferrous acetate are easily absorbed through skin and can cause poisoning, and can kill plants and fish if dumped improperly.

    1 reply

    Thanks. Want to set this up for a bunch of my husband's tools that need help. Doing it the wrong way would not make a happy valentine's day gift.

    You should not use salt (sodium chloride) as an electrolyte. The electrolysis can release the chlorine from the salt. Chlorine gas is extremely toxic.

    1 reply

    This is incorrect. Chlorine is more electronegative than oxygen and has a higher bonding energy. The chlorine will remain strongly attached to the sodium as salt. The 'chlorine smell you observe is not actually from chlorine, it is from hydroxide ions. The two are indistinguishable in terms of smell. Hydroxide can be just as dangerous however. This whole instructable is doing it wrong though. I will elaborate in a seperate comment.

    The rust on the tools looks like freshly prepared with salt( NaCl) ( especially on the pliers. The method is ineffective, 30 minutes to clean a screwdriver? To get a similar effects you need 2-5 minutes, a piece of sandpaper, mineral oil and paper towel to clean afterwards. As an alternative: use metal rotary brush:)

    Great idea, Thanks for sharing!

    Chlorine Gas would be discharged, which should be dealt carefully. Although the quantity is minimal, inhaling it directly, might doze you off. Otherwise, using KOH (potassium hydroxide) might be a better idea, which discharges only HHO gas.

    There is a danger to doing it in this manner. If you notice, the solution and polarity are the same as used in metal etching. If you don't watch it, you can erode the metal too much. Using washing soda as the electrolyte and the part being cleaned as cathode (-), there will be no erosion; the rust is literally knocked off by hydrogen bubble formation on the surface of the part.