How to Convert Rust to Iron Electronically

Removal of rust can be performed in a variety of ways. Most are destructive to the material, because along with the rust, other items items are also removed. Methods that use abrasives can damage the rusted item. Chemical treatment can work wonders, but is also damaging. The least destructive and yet effective means of rust removal is electrolysis, which converts the rust back into iron.

Difficulty: Challenging

Instructions

Things You'll Need:

• Plastic container to hold item
• Thin non-galvanized steel plate
• Small piece of steel rod to use as the anode
• Electrolyte solution (10 percent solution of washing soda)
• Power supply such as a battery charger
• Light bulb to limit current flow, 12V 2.2W bulb

1. Clean the outside surface of the item that needs to have the rust removed, with 90 percent isopropyl alcohol. This will remove any traces of grease or oil from handling. Also, clean the surface of the anode.

2. Submerge the anode in the plastic container that is to be used as the reaction vessel. Make sure that all surfaces of the cathode (item) have a straight line to the surface of the anode. A cage of steel gauze would ideally be the best anode because of its bendability and even current flow. Don't forget to make sure the anode surface is also over the item in question. Both pieces, the anode and the cathode, need to be suspended in the electrolyte solution.

3. Pour in the electrolyte solution so that it covers both the anode and cathode. Washing soda is readily available at most supermarkets and consists mainly of sodium carbonate. Be sure to check the label. It is best to allow this solution to stand undisturbed for at least one full day to allow the sediment to fall to the bottom of the bottle and then only use the upper clear liquid in the reaction vessel.

4. Make sure that there is good connection between the anode and the positive side of the battery charger. The charger should be a low voltage direct current supply. If the resistance of the charger is too low, it presents a hazard to the charger and possible fire. Even if there is no harm done to the charger and no fire occurs, if the current is too high it will give very poor results in the conversion process of rust to iron.

5. Limit the current flow by placing a 12V 2.2W light bulb in series with the item and charger. The light should be placed after the item to limit the current to around 200mA.

6. Make sure that the wire connected to the side of the bulb that is away from the item is firmly connected to the cathode terminal of the battery charger.

7. Ensure that the connection to the item of interest is good. Often it may be necessary to make a small scratch on the surface of the item to expose pure metal. The connection will be made at this point.

8. Turn on the battery charger and begin the process. Generally, it takes about 48 hours for the process to complete. When it is done, there will be a rise in the voltage of about 2V and bubbles of hydrogen will begin to form at the item's surface.

Tips & Warnings

• If the item to be treated contain zinc, nickel, copper or similar metals, some plating of the cathode may occur which will shorten the useful life of the cathode. By changing the cathode periodically, you will avoid this problem.
• Where possible use a steel gauze as the anode to help remove shadowing effects on the cathode.
• At the completion of the process, it is a good idea to carefully remove any remaining rust with a small rotary wire brush and then coat the item in a light film of oil to prevent rust from forming again.
• When the item is in the electrolyte solution always leave the power turned on to prevent corrosion.
• Avoid using any aluminum pieces.
• Always work in a well ventilated area. The fumes of the chemicals as well as the gases that are produced in the procedure are hazardous. Some of the fumes produced are explosive and flammable in high concentration.
• Always work in a well-ventilated area. The fumes of the chemicals as well as the gases that are produced in the procedure are hazardous. Some of the fumes produced are explosive and flammable in high concentration.
• Always wear goggles and gloves when dealing with hazardous chemicals. Due to the slight alkaline nature of the electrolyte solution EXTREME caution must be used as contact with the eye can cause blindness in only a few seconds.

Resources

• Conversion of rust to iron