Mixe
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An arduino controlled pH adjuster
I'm building my first chlorate cell and I'm having issues with the pH adjustment. Beeing a perfectionist, the
"top-it-with-a-little-HCl-every-now-and-then"- approach is not satisfying to me.
So I found this:
Arduino compatible pH sensor
The setup would be: the sensor connected to an Arduino Nano with code that reads it at regular intervals (possibly correcting for temperature also),
compares it to a set value, and then doses HCl or NaOh accordingly through control of two solenoid valves.
The only thing I wonder about is how to get the electrode to survive beeing submerged into the hot, corrosive solution for longer periods of time.
Has anyone done anything like this?
[Edited on 2017-6-4 by Mixe]
[Edited on 2017-6-4 by Mixe]
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unionised
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The pH electrode is glass and will probably survive just fine.
You might need to switch off the electrolysis current for a short while when you take the measurements because that might otherwise upset the voltage
from the pH electrode.
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Melgar
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In practice, pH sensing electrodes don't tend to last very long, and they have to be recalibrated frequently. I was in a research group a while back,
that was studying the potential of using bound pH indicators on a polymer substrate, then measuring their color changes via optical sensors, and
calculating pH from that.
The first step in the process of learning something is admitting that you don't know it already.
I'm givin' the spam shields max power at full warp, but they just dinna have the power! We're gonna have to evacuate to new forum software!
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byko3y
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You should probably be looking for ph buffer rather than some explicit ph adjustment.
[Edited on 15-6-2017 by byko3y]
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hyfalcon
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You might want to read through this:
http://www.amateurpyro.com/forums/blog/2/entry-114-the-bucke...
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unionised
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Quote: Originally posted by Melgar  | | In practice, pH sensing electrodes don't tend to last very long, and they have to be recalibrated frequently. I was in a research group a while back,
that was studying the potential of using bound pH indicators on a polymer substrate, then measuring their color changes via optical sensors, and
calculating pH from that. |
In what amounts to a cell full of hot bleach, I'd bet on the glass electrode lasting longer. than dyed plastic.
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bandil64
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Peristaltic pump
| Quote: Originally posted by Mixe | I'm building my first chlorate cell and I'm having issues with the pH adjustment. Beeing a perfectionist, the
"top-it-with-a-little-HCl-every-now-and-then"- approach is not satisfying to me.
So I found this:
Arduino compatible pH sensor
The setup would be: the sensor connected to an Arduino Nano with code that reads it at regular intervals (possibly correcting for temperature also),
compares it to a set value, and then doses HCl or NaOh accordingly through control of two solenoid valves.
The only thing I wonder about is how to get the electrode to survive beeing submerged into the hot, corrosive solution for longer periods of time.
Has anyone done anything like this?
[Edited on 2017-6-4 by Mixe]
[Edited on 2017-6-4 by Mixe] |
I would definately use a peristaltic pump instead of a solenoid valve. You can control it using two PWM outputs from the Arduino and is much more
precise than simply using a solenoid. If you pick them up from ebay they cost about the same aswell.
Let me know if you need some schematics for the interface circuit.
Regards
Bandil
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Texium
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Thread Moved
27-11-2023 at 11:31 |
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