Cleaning scorched malt from a conical flask

[Dr Jacoby]

I got distracted while heating up a starter recently and some malt extract got burned at the bottom of the flask. I tried soaking it in hot water and I also gave it a good cleaning using oxycleaner but no joy. Any ideas?

[RichC]

Cant say for definite but I'd try lemon juice. I leave freshly squeezed lemon juice on the element of my buffalo for about an hour and the scorching lifts off with the slightest touch.

[Dr Jacoby]

Yea, might give that a go. I tried soaking it in Starsan for a while, which is also acidic, but it didn't do the trick. Cheers

[johnrm]

Look here...
http://www.nationalhomebrewclub.com/cgi-bin/yabb2/YaBB.pl?num=1358778869/7#7

Isn't Drain Cleaner Caustic? Maybe use that.

[Dr Jacoby]

That's exactly what I was looking for  And I get to play with acids 

[Ciderhead]

Don't leave in contact too long!!!

[Will_D]

If you do get the 95% Sulphuric Acid I hope you know the rules:

ALWAYS add acid to water NEVER the other way round.

If you use conc Sulphuric to clean a flask:

Don't just pour in some water when the crud is lifted.
The explosion of boiling acid shooting out of the neck of the Erlenmyer will take your face off!!

What you do is:

If say you've added say 100 ml of acid into the flask pour this into about 20 ml of water.

Carefully add this mix back into the flask, swirl, and pour into about 50 ml of water.

Pour this back into the flask and swirl. Discard the acid () and then it should be safe to slowly add some water to the flask and then it can be rinsed.

I take no responsability for the above advice. Brewers Beware.

Conc Sulphuric is nasty stuff.

Wear some PPE At least a pair of goggles/safety glass and a pair of rubber gloves

Yes, nice pair of yer Ma's pink Marigolds may just save a finger.

The same advice holds for Sodium Hydroxide - also available as a drain cleaner. This is also about as nasty as the acid above.

Same protocols apply

HTH

[Ciderhead]

Wills right, it scared the shite out of me and I amn't afraid of the boogeyman.

[Will_D]

If you get your hands on Sodium it's great fun. Always add water, and stand well back. Lithium is almost as good.

Here's a story from the past:

A young wanabee chemist, let's call him Will had a 16th birthday coming up. Was expecting a cash windfall!!

As he was now literate in English (being of a Welsh nature) he had discovered the 1960s version of e-bay!! I kid you not - it was called "Exchange and Mart" ( still called E&M in UK and Buy&Sell here)

Anyway, under the Science/Chemistry section there was an ad. for "Apparatus and Chemicals"

Long Story Short: A week later the posty man delivered a large package. In exchange for about a 15 shilling postal order I got a 500 gm jar of Sodium (under liquid paraffin) plus a few other dangerous must haves.

This was the good old days! As a 16 year old I could go to a chemist's shop and buy most chemicals "as long as you had a good reason"

So:

conc. Sulphuric "Dad needs to jizz up his car battery"
conc. Hydrochloric "Mortar stain remover"
Sodium Hydroxide " Drains blocked with grease"
conc Nitric: Never had one for this but after the above the chemist stopped asking!

Sodium Chlorate: Just go to a garden shop and buy it buy a 7Kg drum.

Footnote: The weed killer mentioned above was often used to kill a weedy / crappy lawn. So Joe Bloggs down to the garden shop: "7 kg of NaClO3 please". Gets home, reads the instructions:

"Add x grams to the gallon". Joe thinks "If I add a bit more it will do the job a lot quicker!" So he uses about 5 times the amount. Waters his lawn, a day later Bingo the grass and weed are dead dead dead. Next day sun comes out and stays out for a few days.

Dead grass is now bone dry, and liberally dosed with a strong oxidising agent. That night on way home someone flicks a f*g onto the lawn!! WOOMF Up goes the lawn!!

I kid you not - it happened.

Now you know why I love chemistry!

Nerd Alert!! Wife is just switching off the laptop," Calm down Will, Enough of this Already!"

Enjoy