Author Topic: The required time formula  (Read 2434 times)

schiaucu

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The required time formula
« on: April 14, 2017, 11:34:04 PM »
It might be a stupid question but....

Can you tell me, in the required time formula for making colloidal silver that stands

Minutes = mililiters x ppm x 0.015 / miliamps

the value of 0.015 where came from? I've tryed to figure it out but nothing...

Thank you!

Offline kephra

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Re: The required time formula
« Reply #1 on: April 15, 2017, 12:44:58 AM »
It comes from Faraday's law of electroplating.
Each electron carried through the cell from cathode to anode releases one atom of silver by chemically combining it with a hydroxide ion.
So, knowing the weight of silver and the number of electrons passing through for a given time, the weight of the silver in the solution can be calculated.


Ts = (k *  M * V)/(W * I)

Where :
M= Mass in grams to be liberated ((ppm * ml)/1000000)
V = Valence  (number of missing electrons from silver ions = 1)
k = Faraday's constant = 96485
W = Atomic Weight of Anode material (Silver = 107)
I = Current in Amperes  (mA / 1000)
Ts = Time in Seconds.
Tm = Time in Minutes.

In PPM, the formula becomes:
Ts = (ppm * ml *k) / (W * 1000000 * I)
Tm = (ppm * ml *k) / (W * 60000000 * I)
Where:
ml = milliliters
ppm = ppm concentration


OR:
Tm= (ppm*ml*V*1.608)/(W*mA)

For Silver, this reduces to Tm = (ppm * ml *  0.0150)/mA
Ex, 20ppm 250ml = 9.09 minutes at 8.25 mA


EDITED for clarity by kephra
« Last Edit: April 16, 2017, 02:57:00 PM by kephra »
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Offline Art

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Re: The required time formula
« Reply #2 on: April 15, 2017, 02:44:51 AM »
Quote
T = (k *  M * V)/(W * I)

Where :
M= Mass in grams to be liberated
V = Valence
k = Faraday's constant = 96485
W = Atomic Weight of Anode material
I = Current in Amperes
T = Time in Seconds.

In PPM, the formula becomes:
T = (ppm * ml *k) / (W * 60000000 * I)
Where:
ml = milliliters
ppm = ppm concentration
T= time in minutes

OR:
T= (ppm*ml*V*1.608)/(W*ma)

For Silver, this reduces to T = (ppm * ml *  0.0150)/ma
Ex, 20ppm 250ml = 9.09 minutes at 8.25 ma


Easy for you to say!!   ;)

I'm just glad that that information is built into the SilverTron Elite.......it makes making silver nanoparticles so much easier!  :)

Art

schiaucu

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Re: The required time formula
« Reply #3 on: April 15, 2017, 01:15:13 PM »
Thank you Bill, like Art said, it's easy for you to say!  :)

Offline Dean

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Re: The required time formula
« Reply #4 on: April 15, 2017, 01:25:37 PM »
Ask a technical question........
 :o :o :o :o :o :o :o