I used two pieces of 1/4 in aquarium air tubing to make the connects between the two tanks. The two tanks were just clear acrylic like plexiglass, open top, and were actually used for cigar displays in a store. I used another clear piece of plexi to cover the top. The gold comes down from a dirty solution so the gold will still need to be washed with hcl real good. I never used it for anything other that proof of concept model, but the gold that came from it was just as pure as gold dropped from ar except it needed washing. I think i did 5 grams mixed with copper and no silver if i'm not mistaken.
Anyone know how the Shor Simplicity System works?
- Thread starter bswartzwelder
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924T
Well-known member
Palladium,
Most excellent----I simply have to build one of these.
I hope you don't mind me calling it the Palladium Shor antidote
Did you use Sodium Chloride, Ammonium Chloride, or a mixture of the 2?
Cheers,
Mike
Most excellent----I simply have to build one of these.
I hope you don't mind me calling it the Palladium Shor antidote
Did you use Sodium Chloride, Ammonium Chloride, or a mixture of the 2?
Cheers,
Mike
924T
Well-known member
Palladium,
Would a small Titanium anode basket work with no problems in the salt solution?
Cheers,
Mike
Would a small Titanium anode basket work with no problems in the salt solution?
Cheers,
Mike
It should as long as you don't jack the voltage up. If you jack the voltage up you will probably create a cl gas generator. I used about 4 volts. I soldered a piece of silver wire that you can buy from ebay for nearly nothing onto the top and let that be my connection.
I also used a teabag for the anode bag. You can buy them as well as muslin cloth tea sacks on ebay.
I also used a teabag for the anode bag. You can buy them as well as muslin cloth tea sacks on ebay.
bswartzwelder
Well-known member
- Joined
- Oct 24, 2011
- Messages
- 660
Mike,
If you read the entire post from the beginning, you will see the patent numbers. Once you have the patent numbers, you can Google them and read the entire patent. He (Peter Shor) names the chemicals used, their proportions and the process including the sequence of events for the thing to work properly. Palladium has a great drawing of his setup which really helps you understand the mechanics of how everything works.
I believe the catalyst needs to be added in the immediate vicinity of the gold, and just before you turn on the electrical power. Likewise, the filters are critical. If their pore size is too large, gold will pass through. If the pore size is too small, no gold will pass through. Someone on the forum mentioned Coorstek porous ceramic cups as what they believe is being used in the Shor system.
Also, according to the patent information, the temperature of the solution is somewhat critical and works best when elevated. Knowing the size of the cup, I saw an old crock pot at a local flea market and purchased it for $5. I can set the cup in the center, put solution in the cup AND the crock pot and heat everything until it reaches the optimum temperature. The cup is not filled to the top, and the solution in the crock pot cannot be allowed to overflow into the cup, but that should not be a problem.
I wanted to try this system out, like Palladium, 1. just to see if it really works, and 2. because I was intimidated by the thought of using concentrated sulfuric acid in an electrolytic cell. I wanted to purchase one of the Coorstek cups, but was told they are only sold in a case lot of 8. I did purchase 8 of them and they have been sitting around until later when I can build (not operate) the device indoors. I will sell some of them at cost plus shipping if anyone is interested.
Another interesting concept is that the electrode inside the cup can be either the anode or the cathode. THE GOLD IS ALWAYS THE ANODE. If you have a little gold, place your gold IN THE CUP, and connect the gold to the positive terminal of your power supply through a piece of silver wire (I got my silver wire from eBay and ordered a large diameter wire to handle the current). With the gold in the cup, the gold will deplate and land inside of the cup. If you have a lot of gold to deplate, put your CATHODE INSIDE the cup and the GOLD ANODE OUTSIDE the cup. The cup (or in Palladiums case, the filter) acts like a one way revolving door. If the gold is inside the cup, it cannot get out. If the gold is outside the cup, it cannot get in.
My gold, when I try this system out, will be inside four cloth drawstring bags. I will give them a shot of H2O2 just prior to putting them into the outer "ring" of my cell. There will be a copper ring above the cell arranged in a circle. As I lower the bags into the solution, the silver wire connected to the gold will hook over the copper ring completing the circuit. I can do this one bag at a time while monitoring the current flow. The bags are not manufactured to precise tolerances, so some gold may get through. However, in this setup, the deplated gold will still be in the crock pot, just outside of the cup.
Bert
If you read the entire post from the beginning, you will see the patent numbers. Once you have the patent numbers, you can Google them and read the entire patent. He (Peter Shor) names the chemicals used, their proportions and the process including the sequence of events for the thing to work properly. Palladium has a great drawing of his setup which really helps you understand the mechanics of how everything works.
I believe the catalyst needs to be added in the immediate vicinity of the gold, and just before you turn on the electrical power. Likewise, the filters are critical. If their pore size is too large, gold will pass through. If the pore size is too small, no gold will pass through. Someone on the forum mentioned Coorstek porous ceramic cups as what they believe is being used in the Shor system.
Also, according to the patent information, the temperature of the solution is somewhat critical and works best when elevated. Knowing the size of the cup, I saw an old crock pot at a local flea market and purchased it for $5. I can set the cup in the center, put solution in the cup AND the crock pot and heat everything until it reaches the optimum temperature. The cup is not filled to the top, and the solution in the crock pot cannot be allowed to overflow into the cup, but that should not be a problem.
I wanted to try this system out, like Palladium, 1. just to see if it really works, and 2. because I was intimidated by the thought of using concentrated sulfuric acid in an electrolytic cell. I wanted to purchase one of the Coorstek cups, but was told they are only sold in a case lot of 8. I did purchase 8 of them and they have been sitting around until later when I can build (not operate) the device indoors. I will sell some of them at cost plus shipping if anyone is interested.
Another interesting concept is that the electrode inside the cup can be either the anode or the cathode. THE GOLD IS ALWAYS THE ANODE. If you have a little gold, place your gold IN THE CUP, and connect the gold to the positive terminal of your power supply through a piece of silver wire (I got my silver wire from eBay and ordered a large diameter wire to handle the current). With the gold in the cup, the gold will deplate and land inside of the cup. If you have a lot of gold to deplate, put your CATHODE INSIDE the cup and the GOLD ANODE OUTSIDE the cup. The cup (or in Palladiums case, the filter) acts like a one way revolving door. If the gold is inside the cup, it cannot get out. If the gold is outside the cup, it cannot get in.
My gold, when I try this system out, will be inside four cloth drawstring bags. I will give them a shot of H2O2 just prior to putting them into the outer "ring" of my cell. There will be a copper ring above the cell arranged in a circle. As I lower the bags into the solution, the silver wire connected to the gold will hook over the copper ring completing the circuit. I can do this one bag at a time while monitoring the current flow. The bags are not manufactured to precise tolerances, so some gold may get through. However, in this setup, the deplated gold will still be in the crock pot, just outside of the cup.
Bert
924T
Well-known member
bswartzwelder,
It's been a couple of years since I read the 2 main Shor patents, so I don't remember noticing the optimal
temperature info (when I was reading them, I was on a quest to find out what the chemicals really were that
they had given 'stage' names to, and wasn't paying attention to much else).
I've got those patents in pdf format, so I'll have to find them and reread them.
It is very, very interesting that you mentioned the optimal temperature, though, because just last night
I was trying to figure out how I would be able to run this process outside, in the winter.
So, your excellent innovation of running the NaCl fizzer cell (Shor) process in a crock pot just blew my mind,
because of the potential for insulating a crock pot with Kaowool, and being able to run the process outside
at 0-10F.
Perhaps a Nitric cell could also be run outdoors in a crockpot in similarly frigid weather, insulated thusly?
Do you know of a temperature probe that would withstand the NaCl or HNO3, so that remote monitoring of
the electrolyte temperature would be possible?
As an aside, I've been thinking for some time now about suggesting a new section for the forum, for new
members and beginners, that would help guide them through taking a realistic inventory of: their recovery
and refining objectives, the realistic limitations and/or opportunities of whatever physical plant and/or sociopolitical
environments they have to work with, their skill set(s), their learning style, availability of supplies, etc.,
to help them rapidly define an operational profile------that would, in theory, make it easier for the experienced members
of the forum to provide assistance.
It's a thought at this point------I'd be interested in hearing if it makes any sense to you, and other forum members?
Cheers,
Mike
It's been a couple of years since I read the 2 main Shor patents, so I don't remember noticing the optimal
temperature info (when I was reading them, I was on a quest to find out what the chemicals really were that
they had given 'stage' names to, and wasn't paying attention to much else).
I've got those patents in pdf format, so I'll have to find them and reread them.
It is very, very interesting that you mentioned the optimal temperature, though, because just last night
I was trying to figure out how I would be able to run this process outside, in the winter.
So, your excellent innovation of running the NaCl fizzer cell (Shor) process in a crock pot just blew my mind,
because of the potential for insulating a crock pot with Kaowool, and being able to run the process outside
at 0-10F.
Perhaps a Nitric cell could also be run outdoors in a crockpot in similarly frigid weather, insulated thusly?
Do you know of a temperature probe that would withstand the NaCl or HNO3, so that remote monitoring of
the electrolyte temperature would be possible?
As an aside, I've been thinking for some time now about suggesting a new section for the forum, for new
members and beginners, that would help guide them through taking a realistic inventory of: their recovery
and refining objectives, the realistic limitations and/or opportunities of whatever physical plant and/or sociopolitical
environments they have to work with, their skill set(s), their learning style, availability of supplies, etc.,
to help them rapidly define an operational profile------that would, in theory, make it easier for the experienced members
of the forum to provide assistance.
It's a thought at this point------I'd be interested in hearing if it makes any sense to you, and other forum members?
Cheers,
Mike
924T
Well-known member
Wow, I just looked up Sodium Peroxide Na2O2 on ebay to get a rough feel for pricing.......
almost $200 for 125 grams.
It looks like frugality dictates me sticking with the $1.00 grocery store H2O2 (3%)!
Cheers,
Mike
almost $200 for 125 grams.
It looks like frugality dictates me sticking with the $1.00 grocery store H2O2 (3%)!
Cheers,
Mike
Just seal it in something that resists the acid / environment. You could even use a glass tube that's been sealed (melted) in one end and filled with alcohol, oil or some other liquid that doesn't freeze and shatter the tube.924T said:
Göran
solar_plasma
Well-known member
Glass would also be my first choice. Another possibility were to take the teflon foil from a laser printer, make a knot on one end, put the sensor into it, fill with water and make another knot into the other end. Not as pretty as glass, but maybe with a higher temperature conductivity.
If glass, I would not fill it with anything with high vapor pressure and nothing that could react with HNO3 in a dangerous way,if the glass would break, like all flammable liquids would. Better than a liquid, some HNO3-inert metal powder around the sensor and much air in the rest of the tube might be.
if your sensor is made of metal, I would just melt it completely into glas.
bswartzwelder
Well-known member
- Joined
- Oct 24, 2011
- Messages
- 660
Depending on the outside diameter of your probe, Put a sleeve of aquarium airline tubing over it and then heat and smash shut the end. That seals the tubing used in my AP cell very nicely. If you want to put something in it, it really shouldn't matter too awful much (unless you choose nitroglycerine :roll: ). The space you will be filling will not contain more than a very few ml.
As far as a special section of the forum for newbies, everybody here has been (or still is) a newbie. Also, everyone here who has a REAL interest in recovery/refining knows they will get out of the forum what they put into it. If all they want is to be spoon fed, they should move on. There are enough signature lines from the members admonishing them to read Hoke, read the safety section, read this, read that, ad nauseam, and yet they don't. If anyone of average intelligence reads what has been said to most all newcomers, they should understand the position(s) taken on the forum. Perhaps others will think we need a section just for the newcomers. If so, then let's do it. I (quite respectful of your thoughts on the matter), just really don't see a need.
As far as a special section of the forum for newbies, everybody here has been (or still is) a newbie. Also, everyone here who has a REAL interest in recovery/refining knows they will get out of the forum what they put into it. If all they want is to be spoon fed, they should move on. There are enough signature lines from the members admonishing them to read Hoke, read the safety section, read this, read that, ad nauseam, and yet they don't. If anyone of average intelligence reads what has been said to most all newcomers, they should understand the position(s) taken on the forum. Perhaps others will think we need a section just for the newcomers. If so, then let's do it. I (quite respectful of your thoughts on the matter), just really don't see a need.
924T
Well-known member
Palladium,
Is there something about the electrical potential of Titanium that would trigger an abnormally high
output of Chlorine gas in a salt cell?
I'm rather curious about that.
Also, I think your using a teabag as an anode bag is just outrageously cool. Did you look up the pore
size for teabags in advance, or did you just wing it on that one?
Cheers,
Mike
Is there something about the electrical potential of Titanium that would trigger an abnormally high
output of Chlorine gas in a salt cell?
I'm rather curious about that.
Also, I think your using a teabag as an anode bag is just outrageously cool. Did you look up the pore
size for teabags in advance, or did you just wing it on that one?
Cheers,
Mike
bswartzwelder
Well-known member
- Joined
- Oct 24, 2011
- Messages
- 660
SolarPlasma,
Where in a laser printer is the Teflon foil located? I have tor a couple apart, but don't recall seeing anything resembling Teflon. Maybe I saw it and just thought it was nylon or some other man made plastic. My newest laser printer started smoking yesterday, but it only happens when it's actually printing, and stops after the last paper is ejected.
Where in a laser printer is the Teflon foil located? I have tor a couple apart, but don't recall seeing anything resembling Teflon. Maybe I saw it and just thought it was nylon or some other man made plastic. My newest laser printer started smoking yesterday, but it only happens when it's actually printing, and stops after the last paper is ejected.
924T
Well-known member
I was poking around the internet for stray information about fizzer cells, and came across this
at the Ganoskin.com website:
" Unlike the Wohlwill process, the Fizzer cell can treat anodes containing up to 10 percent silver, and up to 20 percent silver if an imposed alternating current is added. The surface of the anode may need to be scraped free of silver chloride at regular intervals."
What is an imposed alternating current?
I know what alternating current is, but not how one would impose it on a DC current.
Cheers,
Mike
at the Ganoskin.com website:
" Unlike the Wohlwill process, the Fizzer cell can treat anodes containing up to 10 percent silver, and up to 20 percent silver if an imposed alternating current is added. The surface of the anode may need to be scraped free of silver chloride at regular intervals."
What is an imposed alternating current?
I know what alternating current is, but not how one would impose it on a DC current.
Cheers,
Mike
bswartzwelder
Well-known member
- Joined
- Oct 24, 2011
- Messages
- 660
I would think an imposed alternating current would be like taking a transformer output and connecting it in series with a DC power supply output. The output terminals from a DC power supply are DC (Direct Current with a + terminal and - terminal). This DC power closely resembles a battery which supplies power in one direction only with a + terminal and a - terminal. A transformer, on the other hand, has output terminal or leads which are AC or Alternating Current. They are NOT considered as a + or - since they are AC.
The transformers I describe below have what is called a center tap. It means that when the transformer is being wound, one end of the wire is brought out and becomes one of the output terminals, lets call it terminal A. Halfway through the winding process, another wire is spliced to the winding wire and also brought out as a lead or terminal. This is the center tap and we'll call it terminal B then the remaining windings are wrapped onto the transformer and the other end of the winding is brought out as terminal C. Connect either one of the terminals (lets use terminal A just to try to keep things simple) to your "cathode". Then, connect terminal B from your transformer to the negative terminal of your DC power supply. We won't use terminal C in this example, so as a safety precaution, it should just be taped up to prevent it from touching anything else. The positive terminal from your DC power supply goes to the anode. Make sure the combined output voltages from the transformer and the DC power supply do not exceed the ratings for either one.
Don't do it yet, but when everything is turned on, the DC power supply will output DC and the AC power supply (transformer) will output AC. With everything still turned off, connect an oscilloscope to the output terminals of your DC power supply. Turn on the O-scope. You will see a straight line (called the trace) going across the screen from left to right. If the frequency adjusting knob on the O-scope is set to a very slow setting, you may see a dot (with a tail following behind it) going from left to right. This dot (or line) should be in the center of the screen. Now, with the voltage knob set to zero, you can turn on the DC power supply. (If you have a current control knob, it can be set anywhere because there will be "essentially" no current flow.) Watching the screen, you will note that nothing has happened. As you increase the output voltage, the trace will move up on the screen, but it should still be a fairly straight line. (If you were to connect the terminals from the power supply to the O-scope backwards, all that would happen is the trace would go down proportionately with the voltage setting.) The new location of the trace is an indication of how high the voltage has been set. The further up the screen, the higher the voltage. It is possible to "ZOOM" in on the trace and look at it in greater detail. Usually, there is still a little bit of waviness in the trace. This is called ripple (not the drinking type). Ripple is an end product of building a DC power supply which uses the AC line for its power source. Best quality power supplies have almost no ripple, and the output will most closely look like a battery. You will pay a lot for this grade of power supply.
Now, with everything shut down again, disconnect your DC power supply and connect the transformer terminals A and B to your O-scope input terminals. Radio Shack still sells transformers. They used to be called filament transformers because they supplied the power to light the filaments in vacuum tubes. Years ago, a common voltage was 6.3 VAC. Today, 12.6 VAC with a center tap at 6.3 volts is very common. With the O-scope turned on, apply power to the input of your transformer. Immediately, the trace changes from a straight line to what should appear as a sine wave (assuming the frequency of the trace is adjusted to replicate the frequency of your power line). Most likely it will be a really nasty looking sine wave because the power companies don't want to spend a fortune "conditioning" the power (for all their customers) any more than they have to. If the frequency knob is adjusted correctly, the trace should go from the zero line and curve upward to a maximum value. It will then reverse and start dropping. Once it reaches the zero line, the voltage will continue to drop even further. While it looks like the voltage is dropping, it is actually increasing in the negative direction. Once it has reached its negative limit, it will reverse again and will approach the zero line from the bottom. The amount of deflection in the positive direction and the negative direction should be opposite and pretty much equal.
Turn everything off, and connect the two power supplies as noted earlier. The two power supplies are connected in SERIES. When turned on, the output at your anode and cathode is a combination of AC and DC. Many people say the AC is riding on top of the DC. The actual voltage seen at the "anode" and "cathode" isn't actually DC OR AC. The actual voltage seen at the anode and cathode is the sum total of what the two power supplies are set at. If the DC power supply is outputting 10 VDC and the AC power supply is outputting 6.3 VAC, then at the instant the line power passes through the zero line, the voltage seen at the anode and cathode is pure DC with a voltage of 10 volts. The transformer is providing a path for the DC to make it from the DC power supply to the load through the anode to cathode, but isn't adding or subtracting anything. As the line power increases to its maximum value, the voltage seen at the anode and cathode is 16.3 volts (10 volts from the DC power supply and 6.3 volts from the transformer). The AC power has reached its peak and reverses. Along its way, it passes through the zero line once again. At that instant, the voltage at the anode and cathode once again becomes 10 volts with nothing being added to or subtracted from by the transformer. The AC power continues its downward journey becoming more and more negative until it reaches the maximum voltage in the negative direction. At this point, the voltage seen by the anode and cathode is 3.7 volts. (10 volts DC which is offset by the negative (-6.3) volts of the transformer = 3.7 volts). Once again, the line power reverses and the transformer voltage decreases until it once again passes through the zero line. In the U.S. this happens 60 times each second and is called 60 Hertz. I believe Europe is on a 50 cycle per second frequency and it is therefor called 50 Hertz. A Hertz is one complete cycle of the AC power, but is usually counted for a period of one second.
There, you have imposed an AC voltage on the output of your DC power supply. In the example above, the DC voltage is greater than the value of the AC voltage, so the anode is always positive to some degree and the cathode is always negative to some degree. If the power supply was set to 6.3 volts (and the transformer was still outputting 6.3 volts), the anode and cathode voltage would swing from 6.3 volts up to 12.6 volts and then down to zero and back to the starting point of 6.3 volts. This can get confusing. Even more so, if the transformer voltage (AC) is higher than the power supply voltage (DC). In that case, the anode and cathode actually change polarity from positive to negative (and vice verse) with every cycle of the line power.
This sounds complicated, and it can be. I have purposely not mentioned things like effective voltage just to keep it as simple as I could.
The transformers I describe below have what is called a center tap. It means that when the transformer is being wound, one end of the wire is brought out and becomes one of the output terminals, lets call it terminal A. Halfway through the winding process, another wire is spliced to the winding wire and also brought out as a lead or terminal. This is the center tap and we'll call it terminal B then the remaining windings are wrapped onto the transformer and the other end of the winding is brought out as terminal C. Connect either one of the terminals (lets use terminal A just to try to keep things simple) to your "cathode". Then, connect terminal B from your transformer to the negative terminal of your DC power supply. We won't use terminal C in this example, so as a safety precaution, it should just be taped up to prevent it from touching anything else. The positive terminal from your DC power supply goes to the anode. Make sure the combined output voltages from the transformer and the DC power supply do not exceed the ratings for either one.
Don't do it yet, but when everything is turned on, the DC power supply will output DC and the AC power supply (transformer) will output AC. With everything still turned off, connect an oscilloscope to the output terminals of your DC power supply. Turn on the O-scope. You will see a straight line (called the trace) going across the screen from left to right. If the frequency adjusting knob on the O-scope is set to a very slow setting, you may see a dot (with a tail following behind it) going from left to right. This dot (or line) should be in the center of the screen. Now, with the voltage knob set to zero, you can turn on the DC power supply. (If you have a current control knob, it can be set anywhere because there will be "essentially" no current flow.) Watching the screen, you will note that nothing has happened. As you increase the output voltage, the trace will move up on the screen, but it should still be a fairly straight line. (If you were to connect the terminals from the power supply to the O-scope backwards, all that would happen is the trace would go down proportionately with the voltage setting.) The new location of the trace is an indication of how high the voltage has been set. The further up the screen, the higher the voltage. It is possible to "ZOOM" in on the trace and look at it in greater detail. Usually, there is still a little bit of waviness in the trace. This is called ripple (not the drinking type). Ripple is an end product of building a DC power supply which uses the AC line for its power source. Best quality power supplies have almost no ripple, and the output will most closely look like a battery. You will pay a lot for this grade of power supply.
Now, with everything shut down again, disconnect your DC power supply and connect the transformer terminals A and B to your O-scope input terminals. Radio Shack still sells transformers. They used to be called filament transformers because they supplied the power to light the filaments in vacuum tubes. Years ago, a common voltage was 6.3 VAC. Today, 12.6 VAC with a center tap at 6.3 volts is very common. With the O-scope turned on, apply power to the input of your transformer. Immediately, the trace changes from a straight line to what should appear as a sine wave (assuming the frequency of the trace is adjusted to replicate the frequency of your power line). Most likely it will be a really nasty looking sine wave because the power companies don't want to spend a fortune "conditioning" the power (for all their customers) any more than they have to. If the frequency knob is adjusted correctly, the trace should go from the zero line and curve upward to a maximum value. It will then reverse and start dropping. Once it reaches the zero line, the voltage will continue to drop even further. While it looks like the voltage is dropping, it is actually increasing in the negative direction. Once it has reached its negative limit, it will reverse again and will approach the zero line from the bottom. The amount of deflection in the positive direction and the negative direction should be opposite and pretty much equal.
Turn everything off, and connect the two power supplies as noted earlier. The two power supplies are connected in SERIES. When turned on, the output at your anode and cathode is a combination of AC and DC. Many people say the AC is riding on top of the DC. The actual voltage seen at the "anode" and "cathode" isn't actually DC OR AC. The actual voltage seen at the anode and cathode is the sum total of what the two power supplies are set at. If the DC power supply is outputting 10 VDC and the AC power supply is outputting 6.3 VAC, then at the instant the line power passes through the zero line, the voltage seen at the anode and cathode is pure DC with a voltage of 10 volts. The transformer is providing a path for the DC to make it from the DC power supply to the load through the anode to cathode, but isn't adding or subtracting anything. As the line power increases to its maximum value, the voltage seen at the anode and cathode is 16.3 volts (10 volts from the DC power supply and 6.3 volts from the transformer). The AC power has reached its peak and reverses. Along its way, it passes through the zero line once again. At that instant, the voltage at the anode and cathode once again becomes 10 volts with nothing being added to or subtracted from by the transformer. The AC power continues its downward journey becoming more and more negative until it reaches the maximum voltage in the negative direction. At this point, the voltage seen by the anode and cathode is 3.7 volts. (10 volts DC which is offset by the negative (-6.3) volts of the transformer = 3.7 volts). Once again, the line power reverses and the transformer voltage decreases until it once again passes through the zero line. In the U.S. this happens 60 times each second and is called 60 Hertz. I believe Europe is on a 50 cycle per second frequency and it is therefor called 50 Hertz. A Hertz is one complete cycle of the AC power, but is usually counted for a period of one second.
There, you have imposed an AC voltage on the output of your DC power supply. In the example above, the DC voltage is greater than the value of the AC voltage, so the anode is always positive to some degree and the cathode is always negative to some degree. If the power supply was set to 6.3 volts (and the transformer was still outputting 6.3 volts), the anode and cathode voltage would swing from 6.3 volts up to 12.6 volts and then down to zero and back to the starting point of 6.3 volts. This can get confusing. Even more so, if the transformer voltage (AC) is higher than the power supply voltage (DC). In that case, the anode and cathode actually change polarity from positive to negative (and vice verse) with every cycle of the line power.
This sounds complicated, and it can be. I have purposely not mentioned things like effective voltage just to keep it as simple as I could.
Bert,
Thank you taking the time to give that great description. I have read of imposing an AC current on DC in the past, but you have provided a simple, clear explanation that even I could understand.
Thanks,
Dave
Thank you taking the time to give that great description. I have read of imposing an AC current on DC in the past, but you have provided a simple, clear explanation that even I could understand.
Thanks,
Dave
Andybrum
Member
Would a bridge rectifier on an ac power supply do the same?
http://upload.wikimedia.org/wikipedia/commons/1/13/4_diodes_bridge_rectifier.jpg
http://upload.wikimedia.org/wikipedia/commons/1/13/4_diodes_bridge_rectifier.jpg
A rectifier bridge as above (four diodes) is used change alternating current to full wave Direct current.
I do not think riding an AC sine wave (50 or 60 cycles per second) on a DC signal would be any good with the cell.
Basically that would be using an AC signal with more voltage on one half of the sine-wave.
I believe you would only want the current to reverse only briefly with DC current being the majority of the current applied, basically a DC signal the majority of the time, with short pulses of reversed current over a period of a longer time of the DC signal, a power supply could do this with an electronic circuit to control the waveform, or it could also be done manually with switches, or relays and a timer.
with electronics it is simple to build a power supply that would basically be A DC power supply, but would impose a reversed current (or an AC current) for a very short period (or pulse) of time over a long period of time of the DC signal.
I do not think riding an AC sine wave (50 or 60 cycles per second) on a DC signal would be any good with the cell.
Basically that would be using an AC signal with more voltage on one half of the sine-wave.
I believe you would only want the current to reverse only briefly with DC current being the majority of the current applied, basically a DC signal the majority of the time, with short pulses of reversed current over a period of a longer time of the DC signal, a power supply could do this with an electronic circuit to control the waveform, or it could also be done manually with switches, or relays and a timer.
with electronics it is simple to build a power supply that would basically be A DC power supply, but would impose a reversed current (or an AC current) for a very short period (or pulse) of time over a long period of time of the DC signal.
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While I can't provide citation (it may be in Hoke), superimposing an AC current on top of a DC current is a process accepted in the operation of a Wohwill cell, where silver content may, otherwise, interfere with operation. It is reputed to cause the silver chloride to shed from the anode instead of forming an impervious layer.butcher said:
This may be one of the rare exceptions whereby contaminants do not limited the useful life of an electrolyte, as the silver chloride is held in the anode bag, not dissolved in to the electrolyte.
Harold
That should be the http://www.ganoksin.com website. Another great site on the web. 8)924T said:
I have read an old book where they described an electrolytic process. They were using a DC generator and an AC generator in series to drive the cells. If properly adjusted the result is that for a short period each power cycle the voltage is reversed, usually 5-10% or less.
When reversing the voltage the process is reversed too and can create some gas on the anode to break off any crust and also remove polarization effects.
I have read about modern plating supplies that uses this principle to reverse the voltage in short pulses to create better plating quality.
Do not connect a DC power supply with a transformer in series. Most DC power supplies would either be damaged by the reverse voltage or would just block the current (in the rectifying diodes).
You need a specialized power supply or a relay switching between two power supplies, one with reversed voltage.
Göran
