Hydrochloric acid and salt pool chemistry

SWGs, salt water chlorine generators, chlorinators,
ozone generators, UV systems, . . .
liwes50541
I'm new here
I'm new here
Posts: 2
Joined: Fri 22 Oct, 2021 10:27

Hydrochloric acid and salt pool chemistry

Postby liwes50541 » Fri 22 Oct, 2021 10:34

Good morning,
I have a question for the chemicals experts here.
Could you confirm that it is advisable to use hydrochloric acid and not sulphuric acid to lower the pH in an salt electrolysis pool?

I suppose so, since part of the hypochlorous acid that we generate with electrolysis reacts with the organic or nitrogenous compounds in the pool, leading to the formation of by-products (and some gaseous that evaporates).
But could we quantify the percentage of salt lost? Or rather, better, of chlorides lost if sulphuric acid is used instead of hydrochloric acid?

Thanks in advice


Denniswiseman
Pool Industry Leader
Pool Industry Leader
Posts: 2594
Joined: Tue 06 Sep, 2011 05:48
My Pool: 10k inground fibreglass, Telescopic Cover, Hayward Powerline pump, Quality filter with glass media, 27kw output heat pump, K-2006C test kit
Location: United Kingdom

Re: Hydrochloric acid and salt pool chemistry

Postby Denniswiseman » Sat 23 Oct, 2021 08:23

I have always used hydrochloric acid (muriatic acid) to lower TA and pH as have most of our fellow pool owners
I can't comment on sulphuric acid
Teapot1
Pool Industry Leader
Pool Industry Leader
Posts: 1203
Joined: Thu 29 Apr, 2021 00:43
My Pool: 12000 gallons vinyl liner,

Re: Hydrochloric acid and salt pool chemistry

Postby Teapot1 » Sat 23 Oct, 2021 11:10

Sulfuric acid add sulphides/sulphates to your pool so like Dennis I keep to as near pure as I can, hydrochloric contains things already in the pool.
I may not give you the answer you want to hear, but I will give an honest opinion of your situation as you decribe it.
liwes50541
I'm new here
I'm new here
Posts: 2
Joined: Fri 22 Oct, 2021 10:27

Re: Hydrochloric acid and salt pool chemistry

Postby liwes50541 » Sat 30 Oct, 2021 03:41

Thank you, but the question was a little more specific: we quantify the percentage of salt lost subtracting from the 4-6 g/L (4000-6000 ppm) of sodium chloride present in the pool, the HClO consumed by reaction and transformed into trichloroamine?
Teapot1
Pool Industry Leader
Pool Industry Leader
Posts: 1203
Joined: Thu 29 Apr, 2021 00:43
My Pool: 12000 gallons vinyl liner,

Re: Hydrochloric acid and salt pool chemistry

Postby Teapot1 » Mon 01 Nov, 2021 03:32

The process is a conversion, brine to HCIO and then back to brine. The salt remains apart from splash out etc.
Not aware that using either acid for pH reduction affects the process in anyway but hydrochloric is cleaner (not adding suphates/sulphites).
Suggest you get back to enjoying the swimming and worry less about the process. Lowering the TA will reduce pH rise just run with the pH a little higher to compensate for the langlier saturation index as pH has a bigger effect than TA and reduces the need for constant pH adjustment.
I may not give you the answer you want to hear, but I will give an honest opinion of your situation as you decribe it.

Return to “Salt Water Chlorine Generators, Ozone, UV”

Who is online at the Pool Help Forum

Users browsing this forum: No registered users and 14 guests