Test if it is possible to explain the know ORP reduction when adding H2O2 into a saltwater

[Hans-Werner]

Both Cu+ and Cu++ can bind strongly to organics.

Ok, but in practical alginate application monovalent cations like sodium and potassium form more or less viscous liquids with alginic acid while divalent cations like calcium and magnesium form gels with alginic acid. In theory this is explained with the "egg box model", where the divalent ions lay between zig-zag-chains of alginic acid like eggs in an egg box.

 

[Randy Holmes-Farley]

Ok, but in practical alginate application monovalent cations like sodium and potassium form more or less viscous liquids with alginic acid while divalent cations like calcium and magnesium form gels with alginic acid. In theory this is explained with the "egg box model", where the divalent ions lay between zig-zag-chains of alginic acid like eggs in an egg box.

Yes, I'm super familiar with divalent cations forming ionic crosslinks with anionic polymers to form hydrogels. Polymer hydrogels for human therapeutic applications has been my professional job for 30 years.

But copper and other transition metals are different than the sodium/potassium vs calcium/magnesium dichotomy because they bind to polymers in other ways.

The picture below shows both Cu++ and Cu+ in a single natural enzyme (cytochrome-a/a3 ), and only one of the 8 bonds shown to copper are the type of ionic bonds that the simple ions (Na+/K+/Ca+/Mg++) form with anions. Notably, the Cu+ is able to form these other bond types to its d electrons just like Cu++.

Fig.2.Copper sulfur cluster of the cytochrome-a/a3 complex, termed CuA,...

Download scientific diagram | Copper sulfur cluster of the cytochrome-a/a3 complex, termed CuA, a Cu2+-and a Cu+-ion (Heldt and Heldt, 2005). from publication: Transition metal complexes and their application in drugs and cosmetics | Inorganic compounds particularly transition metals have played...

www.researchgate.net

 

[Rick Mathew]

Follow up on this question...


I put the ORP probe in straight Prime dechlorinator for ~30min. It pegged the ORP to the lowest value it could measure (-600mV or so). Then rinsed and brushed under tap water and tank water then into the tank.

H2O2 addition after being in the tank for 1.5 hours (+20mV jump) :

And then again after the probe had been in the tank water for 16 hours (+30mV jump):

So the ORP jump up with h2o2 is persistent from one day to the next at least and 2 repeat h2o2 doses after exposing the probe to a strong reducing agent.
And the ORP drop with my probe is persistent for at least a day and 3 repeat h2o2 doses after exposing the probe to a strong oxidizer (1/100 dilution of bleach, ORP goes over +700)
Below are the data runs from the bleach pre-conditioned tests that I earlier posted here in post 224.

h2o2 doses into the tank at 1hr, 16hr and just under 24 hr after probe "pre-conditioned" in bleach.

In the next couple of days I'll see if I can turn off this pre-conditioning effect by cleaning the probe. If so, then it's from the biofilms/deposits on the probe. If not - it may mean that the strong reducer/oxidizer is affecting the internal workings of the probe.

It has taken me a while but I managed to replicate these results. Below are the experimental results.

CHART 1
Chart # 1 is an add to tank tank water of H2O2 at 1mL/10 Gal The sample was in a 1L beaker with stirrer. We see a "typical" drop in ORP

I removed the probe and soaked it in Prime for 30 minutes. Rinsed brushed it in tap water and placed it into the display tank until it stabilized. I removed 1L of water from the display tank in a 1L beaker with stirrer and placed the probe in the beaker. I then added H2O2 at 1 mL/ 10 gal. I then waited for a period of time and made a second add of H2O2 at the same level. The results can be seen in Chart 2.

CHART 2

As you can see in both adds the ORP value increased just as @taricha reported....I escaped to a new "Universe"

I removed the probe and soaked it in 1/100 Cl for 30 Min. Rinsed and cleaned it and put it back into the display take to stabilize. Once it was stabilized I removed it an placed it in the 1L beaker filled with tank water and allowed it to stabilize. I the added H2O2 in the amount prescribed above. The results can be seen in Chart # 3

CHART 3

As you can see I moved back into the old "universe" just as @taricha described.


I then conducted a second experiment that was suggested I think by @Dan_P . I made up a salt solution using reagent grade NaCl at 34 ppt. I placed the probe into the solution (1L Beaker) and let it stabilize. I then added H2O2 at the prescribed amount...The results can be seen in Chart # 4

CHART 4

The ORP increased...I replicated this 2 additional time.

I then removed the probe and placed it into the Display Tank to stabilize. I Removed 1L of tank water and placed the probe into the beaker and waited for the probe to stabilize. I then added the prescribed amount of H2O2. The Results can be seen in Chart # 5

CHART 5

The results are what is "typically" seen with the addition of H2O2... the ORP decreases.

I am not sure if this helps or just adds to the mystery...But none the less here it is

 

[Dan_P]

It has taken me a while but I managed to replicate these results. Below are the experimental results.

CHART 1
Chart # 1 is an add to tank tank water of H2O2 at 1mL/10 Gal The sample was in a 1L beaker with stirrer. We see a "typical" drop in ORP

I removed the probe and soaked it in Prime for 30 minutes. Rinsed brushed it in tap water and placed it into the display tank until it stabilized. I removed 1L of water from the display tank in a 1L beaker with stirrer and placed the probe in the beaker. I then added H2O2 at 1 mL/ 10 gal. I then waited for a period of time and made a second add of H2O2 at the same level. The results can be seen in Chart 2.

CHART 2

As you can see in both adds the ORP value increased just as @taricha reported....I escaped to a new "Universe"

I removed the probe and soaked it in 1/100 Cl for 30 Min. Rinsed and cleaned it and put it back into the display take to stabilize. Once it was stabilized I removed it an placed it in the 1L beaker filled with tank water and allowed it to stabilize. I the added H2O2 in the amount prescribed above. The results can be seen in Chart # 3

CHART 3

As you can see I moved back into the old "universe" just as @taricha described.


I then conducted a second experiment that was suggested I think by @Dan_P . I made up a salt solution using reagent grade NaCl at 34 ppt. I placed the probe into the solution (1L Beaker) and let it stabilize. I then added H2O2 at the prescribed amount...The results can be seen in Chart # 4

CHART 4

The ORP increased...I replicated this 2 additional time.

I then removed the probe and placed it into the Display Tank to stabilize. I Removed 1L of tank water and placed the probe into the beaker and waited for the probe to stabilize. I then added the prescribed amount of H2O2. The Results can be seen in Chart # 5

CHART 5

The results are what is "typically" seen with the addition of H2O2... the ORP decreases.

I am not sure if this helps or just adds to the mystery...But none the less here it is

Rick, how would the H2O2 dip/spike look for a series of serial diluted tank water with saltwate? Would the flip occur in both directions, spike to dip and dip to spike? Would the rise in ORP slowly decline to a dip as more and more tank water was added to brine or would there be a sudden flip from spike to dip? Would space-time collapse to a singularity?

 

[Rick Mathew]

Rick, how would the H2O2 dip/spike look for a series of serial diluted tank water with saltwate? Would the flip occur in both directions, spike to dip and dip to spike? Would the rise in ORP slowly decline to a dip as more and more tank water was added to brine or would there be a sudden flip from spike to dip? Would space-time collapse to a singularity?

I knew you were going to ask me this...I have been thinking about this experiment...also one with adding small amounts of skimmate to the NaCl....a true rabbit hole

 

[Dan_P]

I knew you were going to ask me this...I have been thinking about this experiment...also one with adding small amounts of skimmate to the NaCl....a true rabbit hole

I would join you in the rabbit hole but ORP electrodes are illegal in Connecticut.

 

[taricha]

I then conducted a second experiment that was suggested I think by @Dan_P . I made up a salt solution using reagent grade NaCl at 34 ppt. I placed the probe into the solution (1L Beaker) and let it stabilize. I then added H2O2 at the prescribed amount...The results can be seen in Chart # 4

CHART 4

The ORP increased...I replicated this 2 additional time.

See, this is why you've got to be careful listening to Dan.
I felt like I had a good handle on what was happening and could explain everything you observed as extremely local effects on or in the probe until this NaCl part.

 

[Lasse]

CHART 4

The ORP increased...I replicated this 2 additional time.

I then removed the probe and placed it into the Display Tank to stabilize. I Removed 1L of tank water and placed the probe into the beaker and waited for the probe to stabilize. I then added the prescribed amount of H2O2. The Results can be seen in Chart # 5

May I ask - did you use tap water or RO water when you mix with NaCl? Was it pure NaCl or did it content some E 535 (Na4Fe(CN)6)

Sincerely Lasse

 

[Dan_P]

See, this is why you've got to be careful listening to Dan.
I felt like I had a good handle on what was happening and could explain everything you observed as extremely local effects on or in the probe until this NaCl part.

 

[Dan_P]

May I ask - did you use tap water or RO water when you mix with NaCl? Was it pure NaCl or did it content some E 535 (Na4Fe(CN)6)

Sincerely Lasse

Lasse, what is known about stabilizers added to H2O2? Anything useful there to contemplate or investigate?

 

[Rick Mathew]

May I ask - did you use tap water or RO water when you mix with NaCl? Was it pure NaCl or did it content some E 535 (Na4Fe(CN)6)

Sincerely Lasse

RODI water...The NaCl is lab grade (reagent) NaCl...don't think it has any E535 but I would not sware to it...It is from the Aldon Corp...Here is a picture of the container...I am sure it is not 100% pure

 

[Rick Mathew]

I would join you in the rabbit hole but ORP electrodes are illegal in Connecticut.

That is why I live in Florida...

 

[Dan_P]

RODI water...The NaCl is lab grade (reagent) NaCl...don't think it has any E535 but I would not sware to it...It is from the Aldon Corp...Here is a picture of the container...I am sure it is not 100% pure

Hey, we could send a solution of this salt for an ICP and sorta find out what elements it contains above 1000 ppb

 

[Rick Mathew]

Hey, we could send a solution of this salt for an ICP and sorta find out what elements it contains above 1000 ppb

Right!!

 

[Lasse]

Lasse, what is known about stabilizers added to H2O2? Anything useful there to contemplate or investigate?

From a Google search

Common stabilizers include: Colloidal stannate and sodium pyrophosphate (present at 25 – 250 mg/L) are traditional mainstays. Organophosphonates (e.g., Monsanto's Dequest products) are increasingly common. Nitrate (for pH adjustment and corrosion inhibition) and phosphoric acid (for pH adjustment) also are used.

However - the one I use should be free from stabilizers

I would join you in the rabbit hole but ORP electrodes are illegal in Connecticut.

If you use it in your aquarium - not in a rabbit hole - it is maybe not illegal -- even in Connecticut .........

Sorry - but I´m from Gothenburg - can´t miss a wide open barn door

Sincerely Lasse

 

[Dan_P]

From a Google search


However - the one I use should be free from stabilizers


If you use it in your aquarium - not in a rabbit hole - it is maybe not illegal -- even in Connecticut .........

Sorry - but I´m from Gothenburg - can´t miss a wide open barn door

Sincerely Lasse

You are always seeing the possibilities! I had not thought of that legal loophole.

 

[Rick Mathew]

You are always seeing the possibilities! I had not thought of that legal loophole.

You mean legal "rabbit " holy..

 

[Dan_P]

You mean legal "rabbit " holy..

Your wit is in good form even early in the day

 

[Rick Mathew]

Your wit is in good form even early in the day

Some people say only 1/2 in form

 

[Lasse]

Been silent for a while but after a cleaning 4/9 - my main probe have not been very stable. Now it is more stable and back to normal Probe A Red - cleaning Blue refill oxydator

Probe C Blue - refill oxidator

Probe B Blue - refill oxydator

Time for some test with adding H2O2 again

Sincerely Lasse