Glassware cleaning:

The list of cleaning solutions and methods for specific contaminants presented here should cover most of the glassware cleaning a technician may have to perform. If an automatic dishwasher is used a final rinse with distilled water may be required before drying.
CLEANING SOLUTIONS:
A. Basic permanganate solution.
Dissolve 20g of potassium permanganate and 50g of sodium hydroxide in a litre of water
B. Hot detergent mixture. Use sparingly to avoid excess foaming
C. Propanone
CLEANING METHODS:
A. Stopcock grease (petroleum base)
Dissolve grease in propanone, wash with detergent, rinse with tap water, rinse with distilled water.
B. Stopcock grease (silicone base)
Soak for 1 hour in fuming sulfuric acid in fume-hood, rinse with propanone, rinse with tap water, rinse with distilled water.
C. Fat and oil contamination
Soak in basic permanganate solution, rinse in tap water, rinse in distilled water.
D. Iron stains
Rinse with 10M hydrochloric acid solution, rinse in tap water, rinse in distilled water.
E. Permanganate stains
Swirl a small amount of acidified iron (11) sulfate solution in stained glassware, wash with detergent, rinse with tap water, rinse with distilled water.
Oxalic acid solution also works.
F. Enzyme contamination
Rinse with dilute nitric acid, wash with detergent, rinse with tap water, rinse with distilled water.
Any remaining stains can be treated as follows:
White deposit- soak in sodium metasilicate (5% aqueous).
Carbon deposit- soak in 6g trisodium phosphate and 3g sodium oleate in 100ml water.
Indelible pencil- wash with propanone.
Iodine- soak in sodium thiosulfate solution 25g/L.
Sulfur deposits-soak in dilute solution of ammonium sulfide.
All solutions listed as dilute are approximately 2M.
The rinsing operation must be carried out thoroughly.
When a piece of glassware must be dried quickly after it has been cleaned, a rinse with high grade propanone may be carried out.
The cleaning operation may be simplified by placing stained or contaminated glassware into detergent solution after use.
Spectrophotometer cuvets and other delicate glassware must be handled with extreme care and not subjected to the harsher cleaning agents.

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