Potassium Monopersulfate (Mps)

[Sportbikenut]

Does anyone know if Potassium Monopersulfate (MPS)is similar or same to Sodium Persulfate? Both are listed as oxidizers. Thanks!

[chem geek]

They are both oxidizers, but are not the same. The active part of the potassium monopersulfate (aka peroxymonosulfate) is the HSO₅^- ion while with sodium persulfate (aka peroxydisulfate) it is the S₂O₈^2- ion. This is actually a minor component of MPS as it is sold, at around 3%, and is the contaminant most closely associated with skin irritation. So while it is an oxidizer one could use, it is more likely to irritate than MPS itself.

[quantumchromodynamics]

(I wrote this while chem geek posted. Some info is the same.)

The active ingredient of MPS is potassium peroxymonosulfate, KHSO₅, which is commonly known as potassium monopersulfate. MPS is present as a component of a triple salt with the formula 2KHSO₅•KHSO₄•K₂SO₄ (potassium peroxymonosulfate, potassium bisulfate, and potassium sulfate).

Potassium monopersulfate is commonly confused with potassium persulfate (potassium peroxydisulfate) (K₂S₂O₈), which a known irritant. I have seen some reference to its use in pools, but I think that most references are errors where it is confused with MPS.

Sodium persulfate (sodium peroxydisulfate) (Na₂S₂O₈) would be essentially equivalent to potassium persulfate (potassium peroxydisulfate). I don't think either it is sold for, or suitable for, pool or spa use.

MPS does contain about 3 % Potassium Peroxydisulfate. I believe that it is just an unintended byproduct of manufacturing.

http://www.sciencelab.com/msds.php?msdsId=9926358

[kstuder]

They are both oxidizers, but are not the same. The active part of the potassium monopersulfate (aka peroxymonosulfate) is the HSO₅^- ion while with sodium persulfate (aka peroxydisulfate) it is the S₂O₈^2- ion. This is actually a minor component of MPS as it is sold, at around 3%, and is the contaminant most closely associated with skin irritation. So while it is an oxidizer one could use, it is more likely to irritate than MPS itself.

I have just recently been getting itchy after using my spa. The itch (no rash, mind you) occurs about 12 hours after getting out of the spa (and showering) and lasts 24+ hours, and is very intense. My husband, son and my friend that I soak most often with are not affected. It's mostly on the backs of my legs, and the insides of my elbows and knees. Not so much where my swimsuit covers. We are trying to figure out if it's a pH issue (but our test kit says about 7.6) or if I'm sensitive to the stuff in the MPS. We use chlorine and try to keep the levels between 2-5 ppm, have a Nature 2, and the spa has an ozonator (not sure if it's actually producing ozone). It's a 1996 Sundance Optima, and I had no issues the first 6 months that we had it (bought it refurbished in March 2010). I don't have the itch the first couple of uses after a water change, and the itch is worse if I stay in the tub longer. Help if you can please! I'm afraid to get back in the water!

[simonc]

Sodium persulfate (sodium peroxydisulfate) (Na₂S₂O₈) would be essentially equivalent to potassium persulfate (potassium peroxydisulfate). I don't think either it is sold for, or suitable for, pool or spa use.

http://www.sciencelab.com/msds.php?msdsId=9926358

QCD -

Sodium Persulfate is sold by Kem-Tek as a non-chlorine shock. See the link to their website. Also, here is a link to the MSDS for the product.

In California, this product is sold by Orchard Supply Hardware (a large hardware chain). Via this forum, I discovered that this was not MPS, so I stopped buying it. I switched to the non-chlorine shock sold by Leslie Pools which is MPS. I didn't have any skin irritation problems with Sodium Persulfate, but I was afraid that one of my guests might have a negative reaction.

If Kem-Tek sells sodium Persulfate as "non-chlorine shock", other companies might do the same. As always, it's a good idea to read the label to make sure you know what you are buying. You and others on this forum have been very helpful in educating the rest of us on what to use and not use in our spas. Thanks!

- Simon

[waterbear]

Sodium persulfate (sodium peroxydisulfate) (Na₂S₂O₈) would be essentially equivalent to potassium persulfate (potassium peroxydisulfate). I don't think either it is sold for, or suitable for, pool or spa use.

http://www.sciencela...?msdsId=9926358

QCD -

Sodium Persulfate is sold by Kem-Tek as a non-chlorine shock. See the link to their website. Also, here is a link to the MSDS for the product.

In California, this product is sold by Orchard Supply Hardware (a large hardware chain). Via this forum, I discovered that this was not MPS, so I stopped buying it. I switched to the non-chlorine shock sold by Leslie Pools which is MPS. I didn't have any skin irritation problems with Sodium Persulfate, but I was afraid that one of my guests might have a negative reaction.

If Kem-Tek sells sodium Persulfate as "non-chlorine shock", other companies might do the same. As always, it's a good idea to read the label to make sure you know what you are buying. You and others on this forum have been very helpful in educating the rest of us on what to use and not use in our spas. Thanks!

- Simon

KemTek does love those sulfates (I remember when they used to sell sulfuric acid for pool use. Only advantage is no fumes but sulfates do build up in the water.)

Both sodium persulfate and sodium percarbonate have been sold as "non chlorine shock" particularly to the commercial market but have been pretty much replaced by MPS because the adverse effects both of these have on chlorine levels and ORP readings. Sodium Percarbonate is useful at destroying Biguanide when converting to chlorine and also in clearing a badly fouled 'swamp' quickly and easily with minimum work in about 48 hours (it will even make leaves and stuff float to the top for easy skimming). IMHO, sodium persulfate should not be used in pools or spas.

[quantumchromodynamics]

QCD -

Sodium Persulfate is sold by Kem-Tek as a non-chlorine shock. See the link to their website. Also, here is a link to the MSDS for the product.

In California, this product is sold by Orchard Supply Hardware (a large hardware chain). Via this forum, I discovered that this was not MPS, so I stopped buying it. I switched to the non-chlorine shock sold by Leslie Pools which is MPS. I didn't have any skin irritation problems with Sodium Persulfate, but I was afraid that one of my guests might have a negative reaction.

If Kem-Tek sells sodium Persulfate as "non-chlorine shock", other companies might do the same. As always, it's a good idea to read the label to make sure you know what you are buying. You and others on this forum have been very helpful in educating the rest of us on what to use and not use in our spas. Thanks!

- Simon

OK, thanks for that information. I had seen some references to its use in pools, but I thought that the references were errors where they confused the two.

Here is another company selling sodium persulfate as non-chlorine shock.

http://hyclor.com.au/pdfs/SpaShock.pdf

http://hyclor.com.au/MSDS.aspx