Author Topic: USB POWERED COLLOIDAL SILVER GENERATOR  (Read 5198 times)

VS

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USB POWERED COLLOIDAL SILVER GENERATOR
« on: December 10, 2018, 12:46:29 PM »
I found that USB, which can deliver 5V and up to 2A, is sufficient for the needs of colloidal silver production, besides being the most easily available supply of DC power.
So, I built my colloidal silver generator based on USB power supply, using easily available commercial modules.

SOME INFORMATION ON MY EQUIPMENT
1. USB POWER SUPPLY I used a step-up DC-DC converter, with micro USB input and up to 28V output (0.5$ on Aliexpress, delivery to Italy included). I set the output voltage to 28V and connected its output to the input of a step down CC/CV converter (Constant Current/ Constant Voltage) provided with voltage and current displays (4$ on Aliexpress, delivery included). I set the output voltage to 24V and the current limit to 10 mA (I used a multimeter to read the current, since the resolution of the current display is 10 mA). With these settings, my first 350 mL batch was ready in 1 hour (10 mAh = 10 mA * 1 hour).
https://www.aliexpress.com/wholesale?SearchText=micro+usb+step-up
https://www.aliexpress.com/wholesale?SearchText=Adjustable+Power+CC%2FCV+Step-down

2. GEARMOTOR STIRRER. I fastened a miniature 6V planetary gearmotor on the cap of the jar (2$ on Aliexpress, including delivery), and connected to its shaft a small plastic paddle underneath. It is connected directly to the 5V input of the previously mentioned step-up power supply and delivers about 100 RPM).
https://www.aliexpress.com/wholesale?SearchText=6v+micro+planetary+gearmotor

SOME INFORMATION ON MY PROCESS
1. HONEY REDUCER. I preferred honey, since it has a more consistent composition directly mastered by bees, instead of commercial syrups, whose composition is not declared: 14 drops of solution (1g honey + 18 mL distilled water).
2. ELECTRODES. Anode: 999 silver bulllion. Cathode: 999 titanium sheet (To be overly prudent, titanium is the most biocompatible metal, but any other metal, like copper or stainless steel, would be OK).
« Last Edit: December 10, 2018, 06:11:44 PM by VS »

VS

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Re: USB POWERED COLLOIDAL SILVER GENERATOR
« Reply #1 on: December 10, 2018, 09:46:00 PM »
Ooops! Many thanks, Alex79 for your suggestion.
I updated my spreadsheet, which helps me to follow in real time the concentration, but I failed to include the volume of the batch in the formulas!
I was even deceived by the fact that there was not so much silver oxide on the cathode, and none at all on the bottom of the jar, and the final color is what would be expected for a 20 PPM colloidal silver.
Now I am wondering where the remaining 40 ppm has gone.
The electrolyte and the reducing agent were abundant (5.4 and 6.6 times the moles of silver), but I think to understand that this does not increase the solubility of silver (oxide) in the water, and that the excess should have been collected on the cathode or precipitated.
May be I need to make some more batches in order to "calibrate" my eyes to better estimate how much silver oxide is collected on the cathode.
I heated the batch at 80 °C after I added the reducing solution.
Regarding the picture, I should better have used a white background, since the color of the table makes the Colloidal Silver appear darker than it is. Its true color really matches that of a 20 ppm Colloidal Silver, as seen in many pictures.


« Last Edit: December 10, 2018, 10:15:54 PM by VS »

Offline Neofizz

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Re: USB POWERED COLLOIDAL SILVER GENERATOR
« Reply #2 on: December 11, 2018, 11:50:41 AM »
Now I am wondering where the remaining 40 ppm has gone.
The electrolyte and the reducing agent were abundant (5.4 and 6.6 times the moles of silver), but I think to understand that this does not increase the solubility of silver (oxide) in the water, and that the excess should have been collected on the cathode or precipitated.
May be I need to make some more batches in order to "calibrate" my eyes to better estimate how much silver oxide is collected on the cathode.

You shouldn't get more than a whisper of silver on the cathode. This is part of the job of the sodium carbonate electrolyte. Try weighting it before and after the run to check. You can also try weighting the anode before and after to see how much silver left it.

That sure be one massive size cathode as well. You really only need something one tenth the width of that.

I can't confirm whether or not your electronics set up is delivering the correct current. It seems like you are getting half or less. Or, you would know what the current is you are getting by using an amp meter in line.

One last thing, the spacing between the electrodes makes a difference. An inch and a half is what we are using.
"Be kinder than necessary, for everyone you meet is fighting some kind of battle."

VS

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Re: USB POWERED COLLOIDAL SILVER GENERATOR
« Reply #3 on: December 11, 2018, 01:20:38 PM »
Thank you for your suggestions, Neofizz.
Since I monitor the current with a multimeter, I will rely on this for the moment, after having corrected my formulas.
But I will buy a milligram scale, which will better allow me to monitor the process.
I will also try a smaller cathode, because this makes a 550 Ohm solution, which doesnt allow to set a voltage higher than 5.5V at 10 mA.
The electrodes are spaced 40 mm, so this should be OK.
This evening I will make the next batch!

Offline Gene

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Re: USB POWERED COLLOIDAL SILVER GENERATOR
« Reply #4 on: December 11, 2018, 07:42:43 PM »
Your cathode needs to be significantly smaller.  I run 10ma and found I needed to go to a 24 gauge copper wire to give me a little more ease in adjusting cell voltage (about 1" submerged) otherwise its a bit too touchy. Usually I have about 0.5" to 0.75" submerged.  At 1" submerged, that comes to about 0.065 square inches of wire surface exposed to the cell (about 1.6 square millimeter and yeah I said millimeters). Yeah. tiny.  That "flag" cathode you have is HUGE.  Its no wonder you have issues getting the cell voltage up over 10V.

With that converter, at 10ma, 28 V out, 5VIn you should only be using about 60ma assuming 90% converter efficiency.  2amps at 5V is HUGE but then, these phone chargers are tiny.

That constant current/constant voltage unit has been discussed before and its not nearly accurate enough to make good quality Colloidal Silver (what I recall from the outcome of the discussion). You really need a home-built current limiter.  This could be as simple as an LM317 voltage regulator with a resistor (or potentiometer) following it and its very stable though it requires 3V minimum above your cell voltage (just saying) as operating headroom.

I'm about to do the same thing with that exact same boost converter module (been thinking about it for a while but haven't gotten around to doing it yet). I'm going to power it from one of those little Apple IPhone chargers (the ones that look like maybe a 2cm cube).  Those are 1 amp and thats way overkill but TINY.

You can add the reducing agent at the beginning of the run so long as you keep the cell temperature up over maybe 120F so the reducing agent reduces somewhat quickly, not hours like it does closer to room temp.  Then, you can just continuously produce and raise the PPM to whatever you want because you never have a situation where you're over the solubility limit for silver oxide dissolved in water during the run (what I do) as long as you add enough reducing agent to reduce whatever total PPM your target is (plus a little extra for "insurance"). The added benefit is that when the run is done, you're fully reduced (I let the solution sit maybe 30 minutes to make sure every last bit of IS has been reduced before I gel cap - it does take a little time for the reducing agent to do its thing).

Honey is NOT a good reducing agent.  First off, its NOT consistent regardless what you think and secondly, its dirty. There's even a bit of peroxide in it which I'm not so sure is a good idea as an ingredient in a reducing agent.  Light clear corn syrup is very clean/consistent.  Maltodextrin (as long as you buy it from a reputable source and if you do, try to get one specific DE number so you can compute how much you really need to use), even glucose are clean and consistent.

Maltodextrin is long chains of glucose molecules each hanging on the tail of the next to put it simply. Only the "head" at the very end of the chain can reduce.  The DE number (if you can get single DE maltodextrin which at least in the US at the consumer level is quite difficult - its all mixed bag) refers to its dextrose equivalency.  DE is usually a number ranging from 2 or 3 up to 20 or even a little higher though usually above 20 its referred to as glucose syrup and yeah, its a liquid over 20 usually. If you can find it you want a single DE maltodextrin because then you can compute exactly how much you need for reduction.  The number is a percentage you divide the weight in glucose you need to completely reduce your IS to Colloidal Silver by as a fraction which tells you how much maltodextrin you need.  For instance, if you need 0.1g of glucose (dextrose - same sugar, 2 different names) and you have maltodextrin with a DE of lets say 5 (a.k.a 5% of the reducing power of glucose) you'd compute (0.1g/0.05) = 2grams of maltodextrin.  As you can see, its advantageous to go to a higher DE number but the lower the number, the better a stabilizer the maltodextrin is.  As I said though, in the US at the consumer level we don't have a choice as its "mixed" bag so all we can do is assume a DE number of maybe 3 as a worst case meaning, again for that 0.1g of glucose example, we'd need to use 3.34g of our unknown maltodextrin.

Just so its said, the solubility of silver oxide in water at room temp (thats 75F, not lower) is a hair over 20PPM.  At 150F its about double so about 40PPM.

I do my runs at 150F so the reducer I add at the beginning reduces quickly (maybe 5-10 minutes) so I never have a situation where I'm exceeding the solubility limit for what hasn't been reduced yet.

VS

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Re: USB POWERED COLLOIDAL SILVER GENERATOR
« Reply #5 on: December 11, 2018, 10:27:44 PM »
Thank-you, Gene, for your suggestions.
I had already appreciated some of your posts elsewere.

Unfortunately, my generator was born before I met CSGSforum.
Now, having started to learn from the experiences posted here, I realize that it has been only an intermediate step.
May be I can produce 20 PPM Colloidal Silver with it, but to get farther, more will be needed: heating the jar, stirring more vigorously, regulating the depth of the cathode, and so on.
I will design my next generator after I will have read the posts in CSGSforum, and there are a lot!

As for the cathode, fortunately it is easy to adapt. I will use a titanium strip instead of the plate, and I will use a through plug to adjust its height and get an higher voltage.

As for the constant current/ constant voltage unit, it was really difficult to adjust the current in the milliamp zone, having it a full scale of 5 A. But I added a 1 kOhm trimmer in parallel to two pins of the 10 kOhm trimmer that regulates the current limit (you can see it in the last picture on the top of the module), and now it is pretty easier to adjust. The current was not very stable, but I attributed it to the variable level of the water, caused by the stirring. However it was stable when using a resistor as a load, but I did not verify its stability with still water.

Since in Italy corn syrup in not readily avalable, I used honey, which was one of the possible reducing agents suggested perhaps by Kephra. I think that maltodextrin or glucose are easier to find. The problem will be to know the DE number of maltodextrine or the real concentration of glucose, since glucose products are widely used in confectionery and sold at varied and questionable declared concentrations.

Offline Gene

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Re: USB POWERED COLLOIDAL SILVER GENERATOR
« Reply #6 on: December 12, 2018, 12:21:59 AM »
Regarding maltodextrin and glucose (dextrose), if you buy powder its probably 100%.  If the maltodextrin doesn't have an associated DE number, its mixed bag and then you have to assume the DE # is 2, maybe 3.

I bought a pound of each from a homebrew supply shop.  They even had a 55 gal drum (white HDPE plastic) of glucose syrup though there was no state DE on it nor how much water was used to make it a syrup.  They use maltodextrin in beer making because it imparts a kind of "creamy" characteristic to the beer which I thought was kind of interesting.

I have a friend in Austria who I taught to make Colloidal Silver and he too has issues with getting light corn syrup.  He bought a small jar of glucose from a pharmacy.  It may have cost a bit but you don't need much though you do need a good electronic balance to weigh-out the powder correctly, especially with glucose because of how little you actually use.

You probably have issues finding clear gelatine I bet for when you want to gel-cap your result.  If so, perhaps you can buy it from an amazon.com vendor who would ship into Italy - knox clear gelatine in powder form. Vegetable gelatine will NOT work.  You need "animal" gelatine because this is a protein and thats the trick.  If you coat the silver particles with a protein, given proteins aren't digested in the stomach, all the silver makes it to the upper part of your small intestine where the gelatin is digested, freeing the silver particles where you get damn near 100% absorption.  Gelatine is also a great stabilizer for higher PPM Colloidal Silver.

And yes, as I recall, the issue with the current limiter was for one, setting it to maybe single digit milliamps because for sure, this was NOT the usage model they covered in the design.  As I recall, the other issue was that the display for current didn't have enough decimal places. You really want to display to 1/100th of a milliamp.  You have a multimeter though and these things are highly accurate.  Even crappy ones provide at least 2 decimal places, some 3 or even 4 on low range scales.


Offline Gene

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Re: USB POWERED COLLOIDAL SILVER GENERATOR
« Reply #7 on: December 12, 2018, 12:36:37 AM »
Regarding a simple current limiter,

https://www.onsemi.com/pub/Collateral/LM317-D.PDF

Figure 26. Use a 10 turn potentiometer and it'll be rock solid stable once you set it.  The only caveat is that the LM317 as I recall, needs 3V minimum of headroom (Vin must be a minimum of 3V higher than VOut).

VRef is nominally 1.25V for the LM317 so use that in the equation to calculate the resistance you need for the current you're choosing to use.

Headroom shouldn't be an issue for you.  Just set your boost converter to 28V like you're doing and with the cell set to 10-12V that gives you about 12V of headroom.

This is probably the simplest current limiter you can build - 2 parts.

At least from Aliexpress and off eBay, LM317's in TO-220 (leaded) packages are dirt cheap!  You'll spend dollars buying a good quality panel mount 10 turn potentiometer though but now you'll have a current limiter that can range from nearly 0ma up to perhaps 25ma+, probably much higher than this.

FWIW...

Offline drewcifer

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Re: USB POWERED COLLOIDAL SILVER GENERATOR
« Reply #8 on: December 12, 2018, 06:51:21 AM »
I'm not an electronics expert, but I was able to follow the schematic laid out some time ago in this forum, It used the LM7805 voltage regulator paired with the proper resistor and it seems to work great for me ... Lately, I hear no mention of the LM7805 and all I read are references to the LM317. Should I be using the LM317 instead of the LM7805? Can you help me understand the difference in layman's terms? Even though I was able to build out the LM7805 to my satisfaction, I have to confess, I don't really understand the underlying electrical engineering involved. What's better for Colloidal Silver production the LM7805 or the LM317?
'Bohr was inconsistent, unclear, willfully obscure and right'
'Einstein was consistent, clear, down to earth and wrong'
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VS

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Re: USB POWERED COLLOIDAL SILVER GENERATOR
« Reply #9 on: December 12, 2018, 09:35:07 PM »
Thanks, Gene and drewcifer for your advices on constant current generators.

In this post, I wish to make some more thought about the constant current regulation.

While the water is stirred, the waves in the jar cause some variation in the level of the wet surface of the electrodes and consequently in the resulting resistance of the solution.

A linear constant current regulator, like LM317 or LM7805, can readily react and vary the output voltage, in order keep the current constant.

However, my module uses a switching regulator chip, which requires a capacitor in parallel to the output, in order to filter the PWM (Pulse Width Modulation) and level the output voltage.
This capacitor slows the response time in the constant current mode, so that the output current actually varies somewhat, as the solution resistance varies.
This is not a significant problem in my set-up, since the stirring is moderate, although the measure on the multimeter is a little bit unstable.

But when a strong stirring were needed, the variation of the resistance would be substantial, and a linear regulator would be mandatory.

So I will consider your suggestions in my next set-ups but, before that, I need to read more posts, in order that the new design will be based on the multiple requirements for the various situations in which it will be used.

Offline nix2p

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Re: USB POWERED COLLOIDAL SILVER GENERATOR
« Reply #10 on: December 13, 2018, 02:11:32 AM »
 I'm not an electronics expert, and the "room" has more than one corner; quoting: "LM7805 or the LM317", supposed to increase voltage/amperage supplied to it, by increasing output? Or, it has another purpose. 
Nix
« Last Edit: December 13, 2018, 02:33:30 AM by nix2p »
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Offline Gene

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Re: USB POWERED COLLOIDAL SILVER GENERATOR
« Reply #11 on: December 13, 2018, 04:31:59 AM »
An LM317 or an LM7805 are just linear voltage regulators.  You get lower voltage out than you put in.

The LM7805 is a fixed 5V linear regulator which needs 2-3V of headroom above the output voltage to stay in regulation (meaning about 8V).

The higher the headroom requirement, the less voltage thats available to maintain the correct current flow in the cell. In other words, if you have 20V and need 8V headroom, all you have left to put across the cell in a worst case is 20-8 or 12V.  Not much room.

The LM317 is a variable regulator that can be set with a resistor or two, to any voltage you want above its headroom requirement which is about 3V. 20-3 is 17v - much better.

Of all the current limiters, the 2 transistor one has the lowest headroom requirement (maybe not even 1V). I built one of these because I had the transistors where I didn't have an LM317 where it didn't make any sense to buy one.

Heat is definitely something you need to deal with if you're going to be running higher currents.

Lets say you're using that boost regulator and are setting it to 28V.  You set your cell voltage to 10V.  That means you have 18V across the current limiter. Lets say you're running 20ma (people do with bullion bar anodes). How much power is that which is dissipated in the LM317?  Well power is voltage times current so that'd be 18V * 0.020 = 0.36 watts.  Thats getting up there and for sure beyond the capability of a tiny TO92 pass transistor.  If you want to run 25ma, thats 0.45watts.

The LM317 (or the LM7805) can survive this in a TO220 leaded package and may only ever get "warm".

IMHO, the LM317 is a better solution and the whole circuit is just 2 parts - the LM317 and a current sense resistor (or potentiometer to make it adjustable).

LM317 from china (aliexpress) I've seen as low as 7.8 cents each in the TO220 package (shippping is free) in 10 quantities so all of 78 cents for 10. Yeah, HOW?

If you're going to make a current variable one, go for a 10 turn potentiometer so you can set the current accurately with ease.  Panel mount ones (though NOT cheap) usually can handle watts.  Somehow (I haven't figured out how yet) those tiny little blue square ones that are only about 3/8" square by about 1/4" thick can handle a lot of power too (easily 0.5 watts).  You won't need to be close to that but those tiny things are a pain to adjust because you need a tiny eyeglass screwdriver to fit into the tiny slot in the adjustment screw.  With a panel mount, you just put a big-old knob on it and you're good.

You're only ever going to have to build one so even if it costs you $5 to build one, who cares, right?



Offline Bobby

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Re: USB POWERED COLLOIDAL SILVER GENERATOR
« Reply #12 on: December 14, 2018, 06:03:59 AM »
     RIGHT!!!
"Nearly all men can stand adversity, but if you want to test a man's character, give him power"  Abraham Lincoln

Offline FromTheDen

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Re: USB POWERED COLLOIDAL SILVER GENERATOR
« Reply #13 on: December 14, 2018, 01:31:38 PM »
@Gene: With a SilverTron Elite in hand, I will probably never need to build a Colloidal Silver generator, but just for reference, would you draw out the circuit diagram for a LM317 unit? What would it take to boost the voltage from USB or a lower voltage wall wart? I thought I had diagrams from earlier posts, but I lost them.

Offline chrisflhtc

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Re: USB POWERED COLLOIDAL SILVER GENERATOR
« Reply #14 on: December 14, 2018, 07:23:02 PM »
You could put a few of these https://www.mouser.com/ProductDetail/Semitec/E-501?qs=wgO0AD0o1vv28tZEOZYnWg%3d%3d  in series with your power supply  for constant current in multiples of .5ma I use 3 and with a 24 v .750ma power supply I measure 15.6ma it drifts with temp so I have them clamped to a small sink. ;D you can have .5 ma with one piece.