Not logged in [Login - Register]
 Sciencemadness Discussion Board » Fundamentals » Miscellaneous » Cleaning glassware and other equipment Select A Forum Fundamentals   » Chemistry in General   » Organic Chemistry   » Reagents and Apparatus Acquisition   » Beginnings   » Miscellaneous   » The Wiki Special topics   » Technochemistry   » Energetic Materials   » Biochemistry   » Radiochemistry   » Computational Models and Techniques   » Prepublication Non-chemistry   » Forum Matters   » Legal and Societal Issues   » Detritus

Pages:  1  2    4
Author: Subject: Cleaning glassware and other equipment
j_sum1
Super Moderator

Posts: 3891
Registered: 4-10-2014
Location: Oz
Member Is Offline

Mood: Metastable, and that's good enough.

I came up with an ingenious idea when cleaning up some glassware the other day.

I had a 500mL flask with what seemed to be a particularly persistent deposit. I tried the usual routines -- hot soapy water, lots of mechanical scrubbing, strong base, oven cleaner and as a last resort, piranha solution. Nothing I tried would remove the yellow-brown marks.

I was about to give up and then I tried scrubbing the outside of the flask. Worked like a charm.
Melgar
International Hazard

Posts: 1848
Registered: 23-2-2010
Location: NYC
Member Is Offline

Mood: Aromatic

Ah yes, I think we've all been there more times than we'd like to admit.

As far as your basic organic crud that's not very hard to get off, well, I realized at one point that I was wasting quite a bit of $20/gallon isopropanol, methanol, and acetone just rinsing out organics. Switched to automotive windshield washer fluid as my cleaner of first resort, and I have to say it's a great deal at$2 or so a gallon. I also use it as the coolant for distillation. One nice thing about it is that it doesn't leave residue if you accidentally spill any. Also, mold and other microorganisms will grow in dilute isopropanol. Not so for methanol.

The first step in the process of learning something is admitting that you don't know it already.
CharlieA
National Hazard

Posts: 295
Registered: 11-8-2015
Location: Missouri, USA
Member Is Offline

Mood: No Mood

My go-to cleaning soap, after rinsing with an appropriate solvent, is "seventh generation dish detergent powder". Surprisingly (at least to me) the list of ingredients given on the back of the box is the same as the list of ingredients in the SDS. It is phosphate-free (I guess the old Alconox has bit the bullet?).

Sulaiman
International Hazard

Posts: 1807
Registered: 8-2-2015
Location: England
Member Is Online

I have experimented with acids and bases, oxidisers, detergents ..
I find that whichever cleaning solution is used, mechanical scrubbing always helps a lot,
as they work well and so far show no signs of scratching my flasks insides.
Swirled - not shaken.
They are easy to rinse and re-use.

CobaltChloride
Hazard to Others

Posts: 148
Registered: 3-3-2018
Location: Romania
Member Is Offline

Mood: No Mood

Cleaning a RBF

My distillation apparatus recently came so I decided to acquaint myself with it by distilling some tap water. After the distillation, I noticed there are white streaks on the inside. I tried cleaning with hydrochloric acid as I thought it was some calcium carbonate/ magnesium carbonate, but it didn't go away even after scrubbing with steel scrubbing pads. How do you think I could remove this? I noticed there are white deposits on my pots as well that don't dissolve in HCl, so it's clearly something in the water. It could be calcium sulfate, which would mean it should be removed by hot, concentrated sodium hydroxide (https://pubs.acs.org/doi/abs/10.1021/ie50436a015). What do you think I should use to remove it?
j_sum1
Super Moderator

Posts: 3891
Registered: 4-10-2014
Location: Oz
Member Is Offline

Mood: Metastable, and that's good enough.

A new active discussion happening here:

No new methods suggested AFAICS and so I will leave that one alone for whatever discussion might ensue -- rather than merging it.
Melgar
International Hazard

Posts: 1848
Registered: 23-2-2010
Location: NYC
Member Is Offline

Mood: Aromatic

Using a sponge or a rag attached to the end of a stiff wire (like a coat hanger wire) works well for cleaning things like erlenmeyers and RBFs. You bend it into whatever shape is best suited for reaching the spot you need to get, then work it into position.

The first step in the process of learning something is admitting that you don't know it already.
wg48
International Hazard

Posts: 697
Registered: 21-11-2015
Member Is Offline

Mood: No Mood

 Quote: Originally posted by Melgar Using a sponge or a rag attached to the end of a stiff wire (like a coat hanger wire) works well for cleaning things like erlenmeyers and RBFs. You bend it into whatever shape is best suited for reaching the spot you need to get, then work it into position.

A sccouring pad can also be used with this method.

Also the sponge-backed pad when wet can be made to move round a spherical flask by vigorous shaking of the flask in a circular motion. Stainless steel scouring pads can also be used but there is a risk of scratching the flask.

The scouring pad can also be tie wrapped round a metal weight and used as above.

Borosilicate glass:
Good temperature resistance and good thermal shock resistance but finite.
For normal, standard service typically 200-230°C, for short-term (minutes) service max 400°C
Maximum thermal shock resistance is 160°C
happyfooddance
National Hazard

Posts: 274
Registered: 9-11-2017
Member Is Offline

Mood: No Mood

 Quote: Originally posted by CobaltChloride My distillation apparatus recently came so I decided to acquaint myself with it by distilling some tap water. After the distillation, I noticed there are white streaks on the inside. I tried cleaning with hydrochloric acid as I thought it was some calcium carbonate/ magnesium carbonate, but it didn't go away even after scrubbing with steel scrubbing pads. How do you think I could remove this? I noticed there are white deposits on my pots as well that don't dissolve in HCl, so it's clearly something in the water. It could be calcium sulfate, which would mean it should be removed by hot, concentrated sodium hydroxide (https://pubs.acs.org/doi/abs/10.1021/ie50436a015). What do you think I should use to remove it?

I think it is calcium carbonate... Try hotter HCl. I didn't look at your link, but calcium sulfate is moderately soluble in boiling water, even a good stream of hot water gets it all out any time I've dealt with. Calcium carbonate can be a pain, even with dilute HCl, but if you put 20% in your flask and throw a reflux condenser on it and some heat under it, it should dissolve quickly.
JJay
International Hazard

Posts: 2933
Registered: 15-10-2015
Location: Western Hemisphere
Member Is Offline

Mood:

It is essential to make sure that any traces of calcium are removed before trying things like chromic acid and piranha solution, or you risk forming calcium sulfate, which sometimes sticks to glass. It can be hard to remove, but scrubbing will take it off.

I usually use dilute acetic acid to remove other calcium salts, but it can take a while to react sometimes.

[Edited on 20-7-2018 by JJay]

This is my YouTube channel: Extreme Red Cabbage. I don't have much posted, but I try to do nice writeups once in a while.
Pages:  1  2    4

 Sciencemadness Discussion Board » Fundamentals » Miscellaneous » Cleaning glassware and other equipment Select A Forum Fundamentals   » Chemistry in General   » Organic Chemistry   » Reagents and Apparatus Acquisition   » Beginnings   » Miscellaneous   » The Wiki Special topics   » Technochemistry   » Energetic Materials   » Biochemistry   » Radiochemistry   » Computational Models and Techniques   » Prepublication Non-chemistry   » Forum Matters   » Legal and Societal Issues   » Detritus