Use an aquarium aerator to keep the solution more uniform, and some sort of membrane to capture the slimes and prevent precious metals from contaminating your copper plates. Sreetips uses darcon filters (shop vac filter bag) for his silver refining cell to keep the pmg's from contaminating his silver.
Find or cast a copper mixing bowl. Use it as the cathode and put a filter bag over your anodes to catch the slimes. The circle shape and electric current will slowly stir the liquid in the bowl.
You might try dealing with the stratification problem by using a small pump to draw liquid from the top and discharge it at the bottom. You could minimize stirring up the anode slimes by keeping the velocity of the discharge low. One way to do that would be to make a diffuser by putting a number of small holes in a piece of tubing and discharging the pump output through that. You could also arrange the holes so the flow is directed up instead of into the slimes. I would try putting the intake at one end of the tank and the discharge at the other end. You could use a float to support the intake so it is always at the very top of the liquid.
Very cool to see the finale of this first run! I hope you keep up with this project and manage to make it streamlined and profitable and that it stays enjoyable to you! I'm looking forward to see the beautiful copper bar you're going to make with that mold! :D
It seems too me that the thickness of the copper on the cathodes will increase the resistance of the system. Using stainless steel cathodes would allow you to scrap the copper off every two or three days. Reducing the resistance, and better retention of copper on the cathodes.
You should probably use a perforated bubbler mat about an inch or 2 from the bottom of the cell. Place your anodes on one side of the cell, submerged near the mat. Place your cathodes on the other side of the cell slightly submerged just below the solution surface.
Almost 30 thirty years ago I worked in the plating department for a pcb production company. We used air bubblers and a mechanical system for oscillating the pcbs back and fourth. Also, there were chemical additives for the copper to plate nice and shiny. The baths were continuously filtered as well. We had specialized equipment for measuring the current to be used per panel. In his case, the quality of the Cu plating isn't particularly important.
I don't know if you missed my comment on a previous video but you can put Dacron bags around the anodes and it will catch most of the slime and stop it from mixing with the copper on the bottom of the container.
A fish tank bubbler halfway down in a wide tube that goes between a bit above the bottom and just below the surface will create a quite gentle pump. It will suck liquid at the bottom opening and expel it at the top. If you make it from two pieces of tube that slides inside each other you could adjust the length of the tube to match slime level and surface level. The amount of air will affect the flowrate. If you put it in a corner the flow at the bottom will have the least effect of the slime. A problem with a bubbler is that the bubbles popping will create small amounts of electrolyte mist. Another way to slowly pump electrolyte is with a peristaltic pump. That can easily be run just short periods and at low speed. The return electrolyte can be pumped directly back at the top of the cathodes with a few pieces of tubes to get the concentrated electrolyte back where it is needed the most. As for the slime, sieve it! Any chunks of copper falling off the anode and cathode should be more chunky compated to the fine slime of metal particles that were left after the copper dissolved. Or stirr it and pour it off while still suspended in the electrolyte. Looking forward to the refining video to see what's hiding in the slime. I've got several kilos of copper myself from treating waste from refining.
Just after watching the first 5 minutes, not sure if you explain it later, but from my experience electroplating, the darkened areas mean you're running too much voltage and not enough current. You only need 1 or 2 volts, but you can crank a few amps through there. The lines I can't quite explain either but from what I understand they're called current lines. It just has to do with the direction the currents are flowing through the solution. I can paint something with conductive paint and electroplate it, and it gets those same lines. So that tells me it's nothing to do with the base metal itself. You can turn the piece that your plating and the lines will go a different direction. They seemed to happen more the faster you are plating also. When I electroplate leaves and jewelry, I usually go low and slow, 0.3 v, and about 10ma per sq inch. For a 6 inch maple leaf it will end up at 60-70 ma once it gets fully coated. Then I don't get anomalies like that but instead a nice smooth coating of copper. Still though I would try lowering the voltage and raising the current a little. As long as it's not so high that you're forming bubbles then you should be okay. Edit after watching the whole video, it occurs to me that all of my experiences with copper sulfate and you're working with copper nitrate. I do think you would get a better result if you went with copper sulfate. If you're in Florida I can't imagine it being that much different than Washington and you should be able to find it as a root killer at the hardware store. It's not very expensive either. Under $20 for 2 lbs of crystals, which will make 3 gallons or so of solution.
All of the problems you encountered came from the slimes building up on your anodes. When you get platinum on the surface, everything will start plating out including the copper in solution. This is also what caused spongy deposition and variable voltages. The agitation is to knock the slimes off of the anodes, not to stir up the solution.
You may have this answer already or you may show it later but I suggest you add some fish tank heaters to get the convection currents going to keep things mixed. Just a thought
This is amazing and very informative. If I understand, your goal is to recuperate any precious metals that may have made it through to the cemented copper and that the copper collected on the cathodes would be purer than before. I am starting out with refining and found that I can't use SMB to precipitate my gold (very allergic). I am resigned for now to using copper to cement my gold. After that, I am able to cement the copper out and like you am melting that into bars. Knowing that some gold may have made it through, I plan on using those bars to cement my next batch of gold and repeat the process. That way, any gold that gets through may show up the next time I cement gold. If obtaining pure copper is the goal, I might try the filter basket method that Sreetips uses for his silver and process the slimes collected in the filter. I just need to find a safe way to use SMB.
A deeper tank would reduce the effects of the stratification. I use a fish tank bubbler in a PVC chimney tube. But my process utilizes an anode bag and prevents slime production.
I used to use this process in the lab for analysis. A few things. I know you're after the slime. But one your voltage is way too high. This high voltage will cause the electrolyte to break down into Nitric acid which will try to push the copper back into solution. Also the concentration of your electrolyte is too strong, and is also probably loaded with contaminates. If you dilute your electrolyte use distilled water. You also may have to run the copper several times. You might be better off not using the CuNO3. Instead use distilled water with a small amount of Baking Soda ot Lye. Good luck .
I would worry about the porosity of the bricks collecting some of the copper & gold , maybe use different tub , use some type of water / juice container - with water inside , bricks on top to hold down if need - high enough to keep brick out of electrolyte . Then some type of plastic wing to slowly move electrolyte - to avoid keeping any type of mechanism out of fluid to avoid corrosion .
Have you ever thought that since you are using the Variac to control the voltage, that the input voltage to the battery eliminator may be too low for the regulator in the eliminator to keep the voltage output constant. Try running without the Variac - using the voltage adjust knob on the eliminator to set your desired voltage level. In other words, use the eliminator like it was intended.
Slim trap is probably one of the better ideas. But to be effective it needs to be a reasonably deep trap. There will be some stratification in the trap with poor circulation at the botom where the sludge can settle but your cathode anode compartment will have enough circulation that there wont be any stratification.
Thanks for your vidéo what if You put the anode and cathode the other way it Will go less deep and stratification will be less important in 4 inchs compare to10 inchs of liquid ? For stiring you can put a slow motor with a plastic rod not going to deep with small controller to stir slowly in a corner once a day .i'm Guessing here hope it Will help you getting some idea
I dont know what is a "good" distance to keep between anode and cathode. But in principle, just as a wire has a resistance and double the length of wire doubles the wire's resistance, if you double the distance ions have to travel through an electrolyte you doubled the number of molecules the copper ions bump into as they travel through the electric field. But you don't want the electrodes so close that variations in anode cathode distance and size encourage significabtvuneven coating on the cathode. You may try playing with electrode spacing to see what is a good compromise between consistant plating and reducing resistance by decreasing distance between plates.
Can you set up individual chambers for each anode and cathode, with holes at the top of the liquid level and holes at the bottom of the chamber above expected slime levels at the end. With the density being higher on the one side, it will set up a natural current(flow) though the holes and stir the solution for you. A taller skinnier cell with electrodes to match may help with that. Forget the rails and attach the wires directly to the anodes and cathodes. Or build a clamp so that the rails bite into the copper. I was wondering if having only 1 anode and 1 cathode per cell, then running 3 cells in series would produce a better process. I cant see the meters on your power supply. My phone doesn't have the screen to do that.
Im thinking the reason you have black stuff plating onto your cathode is because you have so much black on the outer layer of your anodes. Why don't you try scrubbing the anodes with a wire brush or something and clean them up. After all your main goal is to remove the impurities from the copper. So if you scrape it off the anodes , you will be removing it from the whole cell
In your voltage measurment are some errors. The display addes all the voltagedrops over the conections. If you measure right between anode and katode you will get a much better value of the voltage between anode and katode. or at least measure the voltage at hte other and of the rails....
how about a hose with valve that comes out from the bottom on one side of the tank it goes into a bucket with a very deep filter ( big vacuum filter maybe ) and a small pump from under the filter to bring it back . did you take into account evaporation , your solution should be much denser after 25 days .
I'm thinking the color variation is do to the extremely dirty and contaminated liquid your using I believe that other metals are getting trapped in the forming crystals on the copper sheets and the density issue is the other metals hanging out lower in the fluid there for trapping more contaminants darkening the copper I believe it's just that simple by the way you should be on prime time maybe abc NBC keep them coming I'm canceling my cable maybe try some Vaseline on contact points to reduce corrosion
If your goal is to recover the slime and not pure copper, maybe stop hyper focusing on the voltage, current and the condition of the copper and focus on containing the slime.
Good thoughts. The main reasons I was so worried about the voltage was to prevent dendrite growth, which kicks into high gear at higher voltage. They could short out the cell, and/or break off and contaminate the slimes. Plus I wanted to prevent electrolysis of water from happening if the voltage got too high.
As pointed out. Excessive voltage creates fragile dendrites that break off and fall in to the sludge which is unfortunate because the point is to seperate the copper from the other metals.
I did that last year and ended up electroforming a copper bowl. Not what I was trying to do, but a pretty cool result. I think I saved a video of it on my profile.
@@scotts834 Yeah man, it even picked up the grain in the stainless, although I'm not sure you can see the detail in the video: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-1R2r0l-gezc.html
Your electric cost, is cost used by the cell not the cost of the wasted power on the return wire on the 120V house hold supply feed. As long as the cell will conduct current the copper will still be extracted from your solution, so your idea of this being the needed amount of copper is solution is not going to work. Do you believe that your messed up the processes that left you this copper so bad that the slime will contain a even detectable amount of PM to warrant processing at this time??? I would not, so are your methods are really in need or refinement that you think so much is lost? I would think you would need run this cell for months on end before the slime's would be worth going after, your not running raw earth mined copper.
