Slightly OT: HCl for Descaling Toilet

[gremlin_95]

Was wondering around B&Q the other day when I came across some 'Super Powerful Toilet Cleaner':

The label had some information on how it is better than HCl based toilet descaling products because HCl 'damages the glaze on porcelain toilet bowls' AND 'fumes from the HCl will eventually damage sanitaryware such as chrome taps'

This is the first I've ever heard something like this, does HCl really damage the glaze? And how would the fumes damage chrome taps? Is there any truth in their statement or is it just some sort of marketing ploy?

I usually use a commercial descaler for my toilet when required and looking at the data sheet, it is indeed HCl based, it is significantly cheaper than the HG product though. IIRC, I only paid around £6.50 for 5 litres.

Data sheet:

It works very well but I wouldn't want to cause any long term damage to the toilet.

[Fredxxx]

Hydrochloric acid dissolves chrome and indeed most base or amphoteric oxides you might find in enamel.

Chrome plate is usually a thin layer, enamel is usually thicker and so much more resilient to acids.

[Brian-Gaff]

I think its the scale that destroys the glaze not the cleaner though in my case its so bad that you still need to scrape it off and the glase is going south rapidly in the bottom and up just round the bend. London has such hard water its criminal. I reckon the big concrete ring main is breaking up andsending all its concrete into our water. Brian

[charles]

London had hard water long before the ring main was built. Here in Surrey we have even harder water - and no ring main. Blame the chalk Downs (or should they be "Ups"?).

[michael adams]

The point about descaling products and possible harm they do is that you shoudn't need to use them more than once, and so cumultaive damage from repeated application shouldn't be an issue. I live in London and cleared quite heavy visible scale years ago with the blue stuff in a black bottle. It was soaked into jaycloths and draped around the pan which had been drained with a ladle. Since then around 1/3 bottle of (now) 28p Tesco thin bleach poured into the lavatory and left overnight or during the day depending on circumstances twice a week, has eliminated any visible build up of further scale whatsoever.

michael adams

...

[David Lang]

The scale may be invisible, but bleach will not remove it.

[polygonum]

It might have been helpful for the label to say what it actually contains.

glycollic acid [looks to me as if it should be single 'l'] Myristamine oxide D-gluconic acid

[David Lang]

COSHH sheet; hydroxyacetic acid 10 - 25% D-Gluconic acid 1 - 2.5%

[Chris Hogg]

The glazes on modern ceramic toilets are fairly acid resistant, up to a point, and certainly more resistant than that on an enamel bath for example. Sanitaryware is fired to temperatures around 1200-1250C (yellow-white heat), whereas enamelled baths are only fired to say

800C (cherry red heat) and hence have much 'softer' compositions. But I wouldn't like to use really strong acid such as 37% fuming HCl, as that may well damage the toilet glaze, and fumes from it might eventually attack chrome plating. Having said that, it's unlikely that any HCl readily available would be strong enough to do either. You'd have to buy concentrated HCl from a specialist chemical supplier to get that sort of strength. IMO their comments are a marketing ploy with just a grain of truth.

[michael adams]

I think the point is supposed to be, that the regular application of bleach in the water prevents the build up of scale in the first place. If that was a troll to get me to go upstairs and run my hand around the inside of the toilet bowl under the water line in search of invisible limescale then you can mark that as a fail.

michael adams

...

[Tim Watts]

IME the odd use will neither damage the glaze nor the joints, even on cemented stone pipework.

If you used it habitually, then yes, it probably would...

[Tim Watts]

Well - in my last post, I was assuming it would not be liberally applied to metalwork of any type :)

[no_spam]

What about brick acid? Is that likely to attack glaze?

[The Natural Philosopher]

I have damaged chrome with strong descalers

But there is no chrome inside my toilets.

[The Natural Philosopher]

WTF do you think brick acid is?

[Fredxxx]

I thought Hydrochloric acid have off HCl vapour. So proximity with taps etc could etch the chrome.

[polygonum]

The claim was that fumes can damage chrome - so the fumes from the HCl in the bog can rise up and wander around the room viciously attacking the taps, plug-hole, even the door handle, towel rail and flush lever/button.

No idea how true or false.

[Tim Watts]

It's not that powerful :)

Yes, it does give off HCl gas (blow over a bottle of conc HCl and it will combine with the moisture in your breath and resemble smoke).

It might possibly make it as far as your seat hinges - but no significant amount will make it much further.

[Tim Watts]

Bollocks :)

If the fumes are that strong, the user is dead.

[Chris Hogg]

HCl gas is highly soluble in water. Only at very high concentrations do you get much HCl vapour above the water. I've just stuck my nose over a container of brick acid, and can hardly smell anything. So the idea that fumes of HCl rise out of the bog and corrode everything in the bathroom is fanciful, bordering on the absurd. Brick acid is about the same strength as laboratory grade, so-called dilute HCl (~18%), which IMO is not 'strong' HCl and doesn't give off fumes. Fuming HCl is ~40% HCl, and that most certainly does give off fumes, as its name implies. You can actually see a 'mist' coming off the surface. Really makes your nose sting if you sniff any!