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flat meniscus in volumetric glass

Discussions about sample preparation: extraction, cleanup, derivatization, etc.

20 posts Page 2 of 2
But without them you would no place to stand.

Rod
Have you tried chromic acid cleaning solution? I seem to remember that it does a nice job on glassware. There's also a discussion in this document about removing grease.

http://www.sigmaaldrich.com/etc/mediali ... _al228.pdf

Aldrich document: AL-228

1. Chromic acid cleaning solution - Use powdered commercial or technical grade sodium dichromate or potassium dichromate.
If the compound is in the form of crystals, grind to a fine powder in a mortar. To 20 grams of the powder in a liter beaker, add a
little water, sufficient to make a thin paste. Slowly add approximately 300mL of commercial concentrated sulfuric acid, stirring well.
Transfer to a glass-stoppered bottle.
Thomas J. Waeghe
MAC-MOD Analytical, Inc.
Chadds Ford, PA 19317
800-441-7508
twaeghe@mac-mod.com
www.mac-mod.com
Use powdered commercial or technical grade sodium dichromate or potassium dichromate.
This is nasty stuff. :twisted: Before trying this, consult the MSDS and take all necessary precautions!!!!!!
Use powdered commercial or technical grade sodium dichromate or potassium dichromate.
This is nasty stuff. :twisted: Before trying this, consult the MSDS and take all necessary precautions!!!!!!
I think it's nastier once dissolved in the sulfuric acid. We don't use this any longer.
Instead of the carcinogenic chromic acid, try NoChromix if interested in a very thorough clean. Its worked well for me and is much safer than chromic acid. It does activate the glass surface.
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