darinventions said:
Ok sorry for not posting on this sooner ..I've been waiting on a copper screen to come in that i ordered on ebay ..the dude forgot to ship it an it took twice as long to get it..anyway i did get to run it an it ran for 45 minutes an held a steady temperature of 57°F...i put all kinds of different gold plated items in with different types of base metals including steel ,bronze ,atonamy,bismuth,tin,an even a little ingot of solder that had some gold on the bottom of it... if you where wondering ..yes this unit is water cooled. an sealed ..i use a small water pump an have a little thermometer mounted on it to monitor the temp..i will be posting pictures of it later in the week ..i thank everyone that shared information pertaining to this ..
Water cooled and sealed? This type of cell produces hydrogen gas, which is highly explosive (refer to the Hindenburg accident). I hope you mean the water cooling is sealed and not the electrolytic cell. If the electrolytic cell is sealed, and close to any water source, you could not only create an explosion, but that same explosion might cause sulfuric acid to come into contact with water, and that I don't imagine would be a good day for anyone close by.
You are using concentrated sulfuric acid in a sulfuric gold deplating cell. If concentrated sulfuric acid comes into contact with water, it will spatter all over the place. The sulfuric acid evaporates the water so fast, that it will splatter far if it comes into contact. Personally, I would never use any sulfuric acid anywhere near water, regardless of how safe you think it might be. It reacts far too violently with water to take that kind of risk.
This is what happens at the anode when you put an electrical current through concentrated sulfuric acid. You are creating persulfuric-acid, Also called Caro's acid, permonosulfuric acid, etc. Under these conditions gold is soluble and the gold ions migrate into solution, as soon as the gold ions go into solution, the persulfuric acid immediately turns back into sulfuric acid and the gold drops back out of solution, finely divided. Once the gold has been stripped, the persulfuric acid attacks the base metals, creating an oxidizing layer and resistance to electrical current. This is the reason when using a car battery charger, you see a drop in the readings. Under these conditions you should never see base metal that looks like new. Not ever. Not unless you are doing something totally outside inorganic chemistry as we know it.
I have made several sulfuric cells. When I am using them, I will stop using one if it becomes hot, and use another. Switching off like this, I feel, is better than attempting to cool with water. I do use material that strips heat from the sulfuric electrolytic cell however. Jewelers use broken up pumice to quickly strip heat from metal. I took this idea and simply bedded the cells in the pumice to strip heat from the cell so I can run each longer, this also cools the cells down faster after use. In this way I not only can run the cell for longer periods of time, but also am not putting myself at risk.
One last note, I know I am repeating myself but I feel this must be included for those who might be new, reading this post, and wish to create a water cooled sulfuric electrolytic cell. Don't. There is no reason to use water to cool an eletrolytic cell. You can always use more than one cell, it's not worth putting your health at risk, or those near you. If sulfuric acid comes into contact with your eyes, it could blind you for life, or cause other damage as well. And never, ever, seal a sulfuric electrolytic cell, the hydrogen gas that builds up is highly explosive.
Scott