Chemical Questions....

[kiamo]

morning folks,

so where to start..., i'm still currently using peroxysan. (just for a few more days, i'm liking

"Nitro's" methods. (by the way, thank you for the wealth of experience available around here.)

but i've got some questions anyways.

-why does peroxysan advise to use no other chemicals? pH, TA and such just don't matter or what? or is it ok to balance these with "traditional" methods?

-i'm trying to find Dichlor and it isn't proving simple. i get a song and dance from dealers around here (in Canada eh.) about getting away from chemicals. eg. no chlorine. they do however recommend lith-chlor. when i pointed out that's still chlorine, well, then i hear about how the chlorine sanatizes, and then the lithium kills the chlorine and "everything else...".

-with regards to using chlorine neutralizer to get rid of the peroxide, (all thanks to "quantumthermodynamics") i'm thinking i'll end up dumping it anyways. but using a chlorine neutralizer to get rid of peroxide confused me a bit...?

anyways, i digress.

the main issue seems to be laying my hands on "Dichlor". maybe i'll have better luck with the bigger dealers in Edmonton? or is it just easier to order via the internet?

on another note, anyone else ever been tubbing when it is SO cold out, the steam turns to snow and falls back on you? exhilerating or what?!

[quantumchromodynamics]

-why does peroxysan advise to use no other chemicals? pH, TA and such just don't matter or what? or is it ok to balance these with "traditional" methods?

pH, TA and calcium do matter and you should balance them. You will have to ask the Peroxysan people about whatever advice they give.

-with regards to using chlorine neutralizer to get rid of the peroxide, (all thanks to "quantumthermodynamics") i'm thinking i'll end up dumping it anyways. but using a chlorine neutralizer to get rid of peroxide confused me a bit...?

Sodium thiosulfate is a reducing agent. It can reduce a variety of oxidizers, such as chlorine, bromine or hydrogen peroxide. Reducing agents supply electrons and oxidizers take electrons.

Hydrogen peroxide oxidizes sodium thiosulfate to sulfuric acid.

4 H₂O₂(aq) + Na₂S₂O₃ --> Na₂SO₄ (aq) + H₂SO₄ (aq) + 3H₂O

[Edit]Here is the reaction of hypochlorous acid and the hypochlorite ion with sodium thiosulfate:

2HOCl + 2OCl^-+ Na₂S₂O₃ + H₂O --> 2Na + 2SO₄^2- + 4Cl^- + 4H⁺

As you can see, the use of sodium thiosulfate is quite acidic and should be used sparingly.[End edit]

Note that I gave this advice in your other post:

It would be best to drain and do a full decontamination procedure, as Peroxysan can leave a tub in an unsanitary condition. See the link in Nitro's signature. Decontamination

If you want to neutralize the hydrogen peroxide, you can use sodium thiosulfate.

I only mentioned using sodium thiosulfate as an alternative if draining and refilling was not an option. I don't think that it is the best way to go. I think that it would be best to drain and refill.

[chem geek]

-i'm trying to find Dichlor and it isn't proving simple. i get a song and dance from dealers around here (in Canada eh.) about getting away from chemicals. eg. no chlorine. they do however recommend lith-chlor. when i pointed out that's still chlorine, well, then i hear about how the chlorine sanatizes, and then the lithium kills the chlorine and "everything else...".

This is complete B.S. and it is irresponsible, if not fraudulent, for the dealer to make any such claim about lithium. Lithium is very much like sodium and is practically inert with respect to spas. Lithium hypochlorite adds chlorine to the spa just like Dichlor, though with Dichlor it also increases Cyanuric Acid (CYA) to moderate chlorine's strength. If you were to use lithium hypochlorite without any CYA in the water, then this would be like using bleach without using Dichlor (or otherwise adding CYA first) and would be too strong for the tub and wear on hot tub covers (and possibly other components) too quickly.

Arghhh! It is so frustrating to hear such blatant lies from dealers. I will give them the benefit of the doubt that they are just ignorant or passing along misinformation from sales reps and not intentionally deceiving, but even so it's very frustrating. By the way, lithium hypochlorite is the most expensive (and probably the most profitable, as a result) form of chlorine you can buy -- 5-6 times more expensive than bleach (for the same FC level) and 3-4 times more expensive than Dichlor.

[kiamo]

-why does peroxysan advise to use no other chemicals? pH, TA and such just don't matter or what? or is it ok to balance these with "traditional" methods?

pH, TA and calcium do matter and you should balance them. You will have to ask the Peroxysan people about whatever advice they give.

-with regards to using chlorine neutralizer to get rid of the peroxide, (all thanks to "quantumthermodynamics") i'm thinking i'll end up dumping it anyways. but using a chlorine neutralizer to get rid of peroxide confused me a bit...?

Sodium thiosulfate is a reducing agent. It can reduce a variety of oxidizers, such as chlorine, bromine or hydrogen peroxide. Reducing agents supply electrons and oxidizers take electrons.

Hydrogen peroxide oxidizes sodium thiosulfate to sulfuric acid.

4 H₂O₂(aq) + Na₂S₂O₃ --> Na₂SO₄ (aq) + H₂SO₄ (aq) + 3H₂O

Note that I gave this advice in your other post:

It would be best to drain and do a full decontamination procedure, as Peroxysan can leave a tub in an unsanitary condition. See the link in Nitro's signature. Decontamination

If you want to neutralize the hydrogen peroxide, you can use sodium thiosulfate.

I only mentioned using sodium thiosulfate as an alternative if draining and refilling was not an option. I don't think that it is the best way to go. I think that it would be best to drain and refill.

[kiamo]

try this again. i'm still figuring out how to operate the computer. lol.

sorry i miss-remembered your name...

thanks for your advice, my intent is to follow Nitro's decon. i'm just hoping the weather stays mild.

my problem at the moment is finding Dichlor. i'm about out of the peroxide and don't really want to re-invest.

thx for clarifying the nuetralizer issue for me.

[quantumchromodynamics]

try this again. i'm still figuring out how to operate the computer. lol.

sorry i miss-remembered your name...

thanks for your advice, my intent is to follow Nitro's decon. i'm just hoping the weather stays mild.

my problem at the moment is finding Dichlor. i'm about out of the peroxide and don't really want to re-invest.

thx for clarifying the nuetralizer issue for me.

No problem, most people get me mixed up with my brother, quantum electrodynamics, which is different from quantum chromodynamics. Quantum chromodynamics relates to the strong or color force, which mediates the actions of quarks by way of gluons.

I can't help you with finding any dichlor. I guess that I'm surprised that it would be such an issue.

[kiamo]

Thanks chem geek very much. That's about the best straight forward explanation i've heard.

i have a 3.5 month old polar spa. has an ozonator on it. i'm definately having my eyes opened

around "here". learn from the best....best way to go!

(maybe i'll learn how to do the quote thing at some point. lol.

[chem geek]

Dichlor will often be called chlorinating granules and will have the ingredient "Sodium dichloro-s-triazinetrione dihydrate" or sometimes "Sodium dichloroisocyanurate dihydrate", possibly without the "dihydrate". Dichlor is sold as GLB Rendezvous Chlorinating Concentrate Granular, Leisure Time Spa 56 Chlorinating Granules, Robarb Sani-Spa, SpaGuard Chlorinating Concentrate, HTH Spa Chlorinating Granules, etc.

[kiamo]

Thx "chemgeek" again. i think that'll make the quest somewhat easier. (at least i've got a better idea of what to look for. i may have to "recheck" those stores...

[quantumchromodynamics]

1 mole of sodium thiosulfate pentahydrate will reduce 4 moles of hydrogen peroxide.

1 mole of (Na₂S₂O₃)(5H₂O) = 248.184 grams.

4 moles of H₂O₂ = 136.059 grams.

1.8241 grams of (Na₂S₂O₃)(5H₂O) will reduce 1 ppm of H₂O₂ in 1,000 liters of water.

0.6904 grams of (Na₂S₂O₃)(5H₂O) will reduce 1 ppm of H₂O₂ in 100 gallons of water.

Example: A 400 gallon tub with a 100 ppm level of H₂O₂ will require 276 grams (9.7356 ounces weight) of (Na₂S₂O₃)(5H₂O). This is equivalent to adding 9.4193 ounces weight of sodium bisulfate (dry acid), which would reduce pH by about 4.0 and Total Alkalinity by about 70 ppm.

(The reference to the sodium bisulfate is for the anhydrous form. The equivalent amount of sodium bisulfate monohydrate would be 10.8333 ounces.)

Due to the large pH and alkalinity decrease, it is not advisable to use sodium thiosulfate to reduce high levels of hydrogen peroxide.

Chlorine takes less sodium thiosulfate per ppm and chlorine levels are typically much less than hydrogen peroxide levels. However, one should use caution when reducing high levels of chlorine due to the acidic nature of the reactant products produced by the oxidation of sodium thiosulfate.

1 mole of sodium thiosulfate pentahydrate will reduce 4 moles of chlorine.

4 mole of chlorine (Measured as Cl₂) = 283.624 grams.

0.8750 grams of (Na₂S₂O₃)(5H₂O) will reduce 1 ppm of Cl₂ in 1,000 liters of water.

0.3312 grams of (Na₂S₂O₃)(5H₂O) will reduce 1 ppm of Cl₂ in 100 gallons of water.

1.1683 ounces weight of (Na₂S₂O₃)(5H₂O) will reduce 1 ppm of Cl₂ in 10,000 gallons of water.

(The Taylor book shows 1.36 ounces weight of sodium thiosulfate pentahydrate per 10,000 gallons to reduce 1 ppm of chlorine.)

This and this calculator gives 1.0 ounces sodium thiosulfate to reduce chlorine by 1 ppm in 10,000 gallons.

Example: A 400 gallon tub with a 10 ppm level of Cl₂ will require 13.24824 grams (0.4673 ounces weight) of (Na₂S₂O₃)(5H₂O). This is equivalent to adding 0.9043 ounces weight of sodium bisulfate (dry acid), which would reduce pH by about 0.4 and Total Alkalinity by about 7 ppm.

(The reference to the sodium bisulfate is for the anhydrous form. The equivalent amount of sodium bisulfate monohydrate would be 1.0400 ounces.)

2HOCl + 2OCl-+ Na2S2O3 + H2O --> 2Na+ + 2H2SO4 + 4Cl-

2HOCl + 2OCl^-+ Na₂S₂O₃ + H₂O --> 2Na⁺ + 2H₂SO₄ + 4Cl^-

0.14695 grams of (Na₂S₂O₃)(5H₂O) will reduce 1 ppm of Br₂ in 100 gallons of water.

[kiamo]

my thanks again! i'm not a chemist, i believe i understand this. if you toned it down for me, thank you! if you didn't, i guess i'm smarter than i thought. lol.

regardless, as you mentioned earlier, sodium thiosulfate oxidizes the peroxide to sulfuric acid.

i suspect that's NOT good for the tub in some manner. and then the swing to balance out

alkilinity, pH, etc.....UGH.

daytime weather's going to mild (supposedly) for the next little while, i'm going to decontaminate, start clean, and attempt to do it right the first time. (actually the 3rd now, lol, but i hadn't discovered this place yet!)

i actually use muriatic acid to adjust my alkilinity (or baking soda) to adjust my TA levels. or rather will again once i get there.

Regards, Roger

[quantumchromodynamics]

Using bleach (sodium hypochlorite) to oxidize hydrogen peroxide would be a better choice than using sodium thiosulfate pentahydrate to reduce hydrogen peroxide, because using bleach is pH neutral.

Sodium thiosulfate pentahydrate is acidic and adds a lot of sulfate to the water. I recommend adding the bleach in stages of a maximum of 15 ppm chlorine at a time.

OCl^- + H₂O₂ --> O₂(g) + Cl^- + H2O

Draining and refilling is still the best overall option.

[kiamo]

Agreed!

I notice many use Taylor kits. I'm presuming all testing kits are not created equal. Are most drop test kits fairly accurate, or are many a relative crap shoot like strips? (don't actually have one yet....) I'm just wondering about something to get by until the "real" one arrives.

[cramp11]

I would 100% recommend emptying the tub and refilling it instead of trying to neutralize the peroxide. When I was having problems with my tub, I made it worse by mixing bleach and peroxide. In the end, decontamination was done, I refilled and haven't had a problem since. *knock on wood*

As for peroxysan not needed anything else balanced (pH, TA, etc)... our dealer or peroxysan (I can't remember which) said that peroxide doesn't react to a high or low pH, TA, etc. Chlorine and Bromine do. If it's too low, something bad happens... if it's too high, some other bad thing happens.

I sort of balance the pH and TA, but only test once in awhile with a crappy strip. As long as I keep my peroxide level over 100ppm... it seems ok. My tub was filled Nov 28/09.

[kiamo]

Hi cramp,

i had read through your previous threads before i joined actually. Up until now my only issues seemed to be the associated pH, TA, and so on. mine are currently entirely out to lunch. last nite pH was @ about 8.4, TA was about 180 (or higher, thats where the strips top out.)

As well, there's the sanatizing concerns. And the stuff is really expensive!

As of last night (Iwas going to start another thread) we"ve noticed little "bumps" on the shell of the tub. kind of like tiny little barnacles, 10 or so per square inch at the moment.

I'm also a newbie and haven't seen this before.

I'm wondering if it's some sort of "scale", or something worse.....

Thankful decon procedures start soon....