[mcarson]

Apologies about my first post being about safety - should have considered this before ordering...

I have, stored securely, about 500ml of Hydrochloric Acid 36.2%. I ordered this originally based on my Father's advice on how to remove built-up lime-scale and other 'substances' from the bathroom of a property I have recently purchased.

Thinking at the time that this was the stuff I used to use back in secondary school, I ordered the only available concentration at the time; 36.2%. After some research on the Internet I have been led to believe that this is extremely dangerous to handle and I would be required to dilute it before general use, or disposal (neutralisation).

I have used every off-the-shelf product to no avail. What concentration and/or handling instructions would you recommend for using (or safely disposing of) HCl? And for safe dilution?

[fledarmus]

"extremely dangerous to handle" is a bit of a stretch. There are much worse compounds. It is sufficiently dangerous to require careful handling, however. You definitely need to dilute it before using it, and neutralize it before disposing of it.

The typical home use hydrochloric acid is commonly sold as muriatic acid in around 10-12% concentrations and should also be diluted, usually to around 1 or 2% before most uses. If you've never handled mineral acids and want to use hydrochloric acid as a cleaner, you might be better off donating your bottle to a local university professor under the table to avoid the red tape involved in moving any hazardous materials, and get some muriatic acid along with the instructions for use instead.

If you do decide to use your 38% solution, remember to wear rubber gloves and safety goggles at all times when using it, and when you are doing dilutions, NEVER ADD WATER TO ACID. (That will liberate large quantities of HCl gas - see below)  . Always add your acid slowly to the water, with stirring, in a large container. Make sure you have plenty of ventilation and avoid getting your face directly over the container - hydrocloric acid is a gas dissolved in water, and there will be some hydrochloric acid vapor whenever you are using it. It can irritate your nose, but if handled carefully isn't much worse than many other household cleaners.

Edit: corrected by Borek, just in case someone will read it later.

[Borek]

NEVER ADD ACID TO WATER

Exactly the opposite.

[mcarson]

Thanks for your prompt reply.

Also, thanks for the heads-up on adding water to acid, eh, acid to water?

?adding acid to water will cause the acid to spit, whereas water to acid (slowly) will cause an exothermic (but stable) reaction? Kind important though (better not smoke!)

I own a mask with A2B2E1 and P2 particulate filters, a pair of polycarbonate safety glasses and compatible gauntlets (probably going overboard!) - Can I use glass or polycarbonate to perform dilution?

For neutralisation is it safe (stable) to use sodium hydroxide (NaOH 99.9% Pearl) in solution, or is this exothermic (extremely) releasing hazardous gases?

And, slightly off-topic, will I keep it away from Sodium Hypochorite (NaOCl 14%), as some info I have researched indicates that this will release dangerous levels of Chlorine (among others)

Thanks in advance

[Arkcon]

Do it the way you outghta
Always add the acid to the water

and just so you know, who am I, http://www.chemicalforums.com/index.php?topic=30398.msg116845#msg116845

[fledarmus]

NEVER ADD ACID TO WATER

Exactly the opposite.

Sorry, wrote it one way, then only edited half of it to write it the other way - I don't suppose you can edit my post to get rid of that completely stupid statement? 

[mcarson]

Thanks for the link; I (now) understand the reasons why adding water to acid is a bad idea (in non-controlled environments).

So, for dilution? Is 8-10% a relatively safe concentration? - with gloves, but not mask? Any plastics I need to worry about? I would also like to use a spray type bottle - just like anti-bac spray, but for 'general' use. (or is this a BAD idea?) - my dad used to use this kinda stuff in his pub to clean the 'facilities'?

[mcarson]

you might be better off donating your bottle to a local university professor under the table to avoid the red tape involved in moving any hazardous materials

Red tape - you're not joking. It costs me more to dispose of the stuff than it costs to buy it.

[Borek]

Sorry, wrote it one way, then only edited half of it to write it the other way - I don't suppose you can edit my post to get rid of that completely stupid statement? 

I can.

If it makes you happy, I did my best to screwup todays problem of the week.