Washing glass issue

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CattMurry

Well-known member
Joined
Jul 26, 2020
Messages
117
Has anyone ever seen this?
Here's the rundown. Bought 6 Erlenmeyer flasks. I washed one with a dish washing wand that was in dish soap water (used for glasses). The medium sized wand was not long enough to reach the bottom, so I did what I could and rinsed thoroughly. Went on to the other flasks, but decided to just rinse them. When I put the 3 together I noticed that the first one had droplets of water everywhere, and almost a steamy look, or condensation on the inside except where the wand could not reach. It looks like a perfect line from the condensed tiny droplets to the clear glass. The other 2 flasks that were just rinsed slid the water down them in perfect uniform fashion, and pooled the water at the bottom, so it then could just be poured out. They dry so much faster. I cannot find what this invisible residue is in the soap whatsoever online. All I am seeing is goofy people saying soap leaves suds, or film if not rinsed (like duh). I washed/rinsed the flask in isopropyl alcohol, then rinsed with purified water. Nothing. Tried my HCL of 32% (20 baume), and NADA. What is this stuff???
 
Hard to say what it could be, but sometime things can get embedded in the glass pretty good. When I was doing analytical undergraduate research, I needed ultra-pure reactions with no contamination. To get my glassware this clean, we would soak it in a caustic solution (in my case it was a saturated sodium hydroxide/isopropyl solution overnight) then after it was done the glass would be re-protonated with some hydrochloric acid (1 Molar). This would pretty much clean just about anything off the glass that we were using in our research lab. Below is a Red Nile video explaining it in further detail.



Recipe for a Base-Bath Cleaning Solution Preparing a base-bath solution:

o Put on thick black gloves, rubber apron, eye protection, and a face shield!
o Get a large plastic container (~5 gallon)
o Add approximately 200-300g of solid KOH pellets (sometimes NaOH is substituted)
o Add 4 L of isopropyl alcohol o Carefully add 1L of deionized water
o Leave the bucket in secondary contain (i.e. sink) until KOH is dissolved and it has cooled back to room temperature before storing
o Replace cover to plastic container.
o Label container with current date and a sign that says “DANGER: BASE-BATH SOLUTION”.

Always use an apron, eye protection, and thick black gloves when manipulating glassware around the base bath! Rinse gloves after use to prevent spreading caustic all over your work area. HIGHLY CAUSTIC!

Harvard's Instructions on Base Bath

https://www.ehs.harvard.edu/sites/default/files/lab_safety_guideline_base_bath.pdf
 
Hard to say what it could be, but sometime things can get embedded in the glass pretty good. When I was doing analytical undergraduate research, I needed ultra-pure reactions with no contamination. To get my glassware this clean, we would soak it in a caustic solution (in my case it was a saturated sodium hydroxide/isopropyl solution overnight) then after it was done the glass would be re-protonated with some hydrochloric acid (1 Molar). This would pretty much clean just about anything off the glass that we were using in our research lab. Below is a Red Nile video explaining it in further detail.



Recipe for a Base-Bath Cleaning Solution Preparing a base-bath solution:

o Put on thick black gloves, rubber apron, eye protection, and a face shield!
o Get a large plastic container (~5 gallon)
o Add approximately 200-300g of solid KOH pellets (sometimes NaOH is substituted)
o Add 4 L of isopropyl alcohol o Carefully add 1L of deionized water
o Leave the bucket in secondary contain (i.e. sink) until KOH is dissolved and it has cooled back to room temperature before storing
o Replace cover to plastic container.
o Label container with current date and a sign that says “DANGER: BASE-BATH SOLUTION”.

Always use an apron, eye protection, and thick black gloves when manipulating glassware around the base bath! Rinse gloves after use to prevent spreading caustic all over your work area. HIGHLY CAUSTIC!

Harvard's Instructions on Base Bath

https://www.ehs.harvard.edu/sites/default/files/lab_safety_guideline_base_bath.pdf

I like the solution thanks! It's messing with my OCD pretty bad.
 
Hard to say what it could be, but sometime things can get embedded in the glass pretty good. When I was doing analytical undergraduate research, I needed ultra-pure reactions with no contamination. To get my glassware this clean, we would soak it in a caustic solution (in my case it was a saturated sodium hydroxide/isopropyl solution overnight) then after it was done the glass would be re-protonated with some hydrochloric acid (1 Molar). This would pretty much clean just about anything off the glass that we were using in our research lab. Below is a Red Nile video explaining it in further detail.



Recipe for a Base-Bath Cleaning Solution Preparing a base-bath solution:

o Put on thick black gloves, rubber apron, eye protection, and a face shield!
o Get a large plastic container (~5 gallon)
o Add approximately 200-300g of solid KOH pellets (sometimes NaOH is substituted)
o Add 4 L of isopropyl alcohol o Carefully add 1L of deionized water
o Leave the bucket in secondary contain (i.e. sink) until KOH is dissolved and it has cooled back to room temperature before storing
o Replace cover to plastic container.
o Label container with current date and a sign that says “DANGER: BASE-BATH SOLUTION”.

Always use an apron, eye protection, and thick black gloves when manipulating glassware around the base bath! Rinse gloves after use to prevent spreading caustic all over your work area. HIGHLY CAUSTIC!

Harvard's Instructions on Base Bath

https://www.ehs.harvard.edu/sites/default/files/lab_safety_guideline_base_bath.pdf

Got it. Somehow Isopropyl alc, HCL, and water did nothing yet baking soda in water to boil got it right off. lol. Back to uniform liquid flow, and quick drying.
 
Hard to say what it could be, but sometime things can get embedded in the glass pretty good. When I was doing analytical undergraduate research, I needed ultra-pure reactions with no contamination. To get my glassware this clean, we would soak it in a caustic solution (in my case it was a saturated sodium hydroxide/isopropyl solution overnight) then after it was done the glass would be re-protonated with some hydrochloric acid (1 Molar). This would pretty much clean just about anything off the glass that we were using in our research lab. Below is a Red Nile video explaining it in further detail.
my daily routine in a lab :) our recipee consist of 4 L water, 1 L isopropanol, 250g NaOH or KOH. different ammounts of water/IPA, similar output. but it happen some time (mainly with some nasty transformations at elevated temperatures), that some junk (polymers/metal salts etc..) from the reaction sticks to the glass and isnt removed by pretty much anything (acetone, basic bath, acid, water etc...). if the ultrasound bath doesn´t help to get it off, there are some "methods of last choice", like 35%HCl/DMSO, HNO3, or even Piranha :) glass containers, flasks or apparatus in general greatly tolerate wide range of acids, but are much less resistant to bases such as NaOH.
prolonged cleaning (forgetting about your dishes in the bucket for month :D ) in the basic bath described above sometimes led to "whitening" the glass (developing milky "patches") or even cracking of some testtubes or round bottomed flasks. heat stress/sharp temperature changes also accelerate this behavior.
 
my daily routine in a lab :) our recipee consist of 4 L water, 1 L isopropanol, 250g NaOH or KOH. different ammounts of water/IPA, similar output. but it happen some time (mainly with some nasty transformations at elevated temperatures), that some junk (polymers/metal salts etc..) from the reaction sticks to the glass and isnt removed by pretty much anything (acetone, basic bath, acid, water etc...). if the ultrasound bath doesn´t help to get it off, there are some "methods of last choice", like 35%HCl/DMSO, HNO3, or even Piranha :) glass containers, flasks or apparatus in general greatly tolerate wide range of acids, but are much less resistant to bases such as NaOH.
prolonged cleaning (forgetting about your dishes in the bucket for month :D ) in the basic bath described above sometimes led to "whitening" the glass (developing milky "patches") or even cracking of some testtubes or round bottomed flasks. heat stress/sharp temperature changes also accelerate this behavior.
Yeah basic or caustic baths can etch, eat, and make glass brittle with long exposures. I thought acids would decompose anything oily in the dish soap residue, but I was apparently wrong (I'm sure more concentrated solutions may have worked). This is why I made the basic brine bath with boiled water, and baking soda. I used every acid I had available at first to no avail haha. For those plastics, and nasty junk Piranha solution, HCL, and nitric seem like pretty decent choices. They all will at least jellify plastics/paints, or eat away most nearly anything else. Good tips for stubborn residues.
 
The cloudy film that forms on the outside may tin oxide if you process material that contains tin. The film on the inside is most likely salt oxides. While scrubbing will will physically remove the film, it will scratch the glass. I have found that using differing PH solution will dissolve almost all metal oxides. I start with ammonia on heat until hot. Decant and rinse with distilled water. Next is dilute HCl to remove any soluble salts converted by the ammonia. A dilute solution of NaOH is next, no extra heat needed. Next is market brand acetic acid (vinegar). Follow this with mild soap and water. Some oxides are dissolved by strong bases. Other are dissolved by strong acid. The final rinses are used as a final raising and lowering of PH before the soap and water. For tungsten oxide, ammonia will remove some but not all. Do not process tungsten containing material in flasks or bottles or store solutions in them. Use beakers or reaction vessels that the top can be removed. Glass polish on a buffer pad can smooth some tiny scratches or help buff out tougher oxides like tungsten oxide but polishing glass removes a layer of glass. If polishing is viable for high end and expensive reaction chambers with removable top, keep track of maintenance dates and remarks of polish used and duration.
 
The cloudy film that forms on the outside may tin oxide if you process material that contains tin. The film on the inside is most likely salt oxides. While scrubbing will will physically remove the film, it will scratch the glass. I have found that using differing PH solution will dissolve almost all metal oxides. I start with ammonia on heat until hot. Decant and rinse with distilled water. Next is dilute HCl to remove any soluble salts converted by the ammonia. A dilute solution of NaOH is next, no extra heat needed. Next is market brand acetic acid (vinegar). Follow this with mild soap and water. Some oxides are dissolved by strong bases. Other are dissolved by strong acid. The final rinses are used as a final raising and lowering of PH before the soap and water. For tungsten oxide, ammonia will remove some but not all. Do not process tungsten containing material in flasks or bottles or store solutions in them. Use beakers or reaction vessels that the top can be removed. Glass polish on a buffer pad can smooth some tiny scratches or help buff out tougher oxides like tungsten oxide but polishing glass removes a layer of glass. If polishing is viable for high end and expensive reaction chambers with removable top, keep track of maintenance dates and remarks of polish used and duration.
Now that's the cleaning ladder rundown right there, but I'd still watch soaps. Like my experience they seem to do something with how fluids interact with the inside surface of the glass (dishsoap in my case). Otherwise awesome cleaning process haha.
 
Now that's the cleaning ladder rundown right there, but I'd still watch soaps. Like my experience they seem to do something with how fluids interact with the inside surface of the glass (dishsoap in my case). Otherwise awesome cleaning process haha.
Most likely surfactants. I've never had a problem with dawn dish soap. Rinse in hot water a few times and a final rinse in distilled water. If the glass is to be used for silver dissolution and silver chloride is undesirable, bake the glassware at a temp of 215°F for an hour to destroy any residual hypochlorite in municipal water supplies. It is nearly impossible to completely rinse chlorine from glass.
 
Most likely surfactants. I've never had a problem with dawn dish soap. Rinse in hot water a few times and a final rinse in distilled water. If the glass is to be used for silver dissolution and silver chloride is undesirable, bake the glassware at a temp of 215°F for an hour to destroy any residual hypochlorite in municipal water supplies. It is nearly impossible to completely rinse chlorine from glass.
It's hard to notice. I only noticed the soaps effects because I could see a perfect line where the soapy wand couldn't reach. Nothing to do with the tap water/CL2/ or it's minerals, or other contaminants. The other new glass, and the bottom of this piece of glass acted uniform in the liquids flow in them with whatever water (distilled, purified, and tap all did the same). These were brand new pieces, and this thread is just my curiosity of what effect the soap had on the glass, and how to clean it which I did figure out myself luckily. I hit this flask with everything haha IPA, HCL, and water rinses. Nothing happened, but I found the solution. Boiling water/Baking soda mix destroyed the whatever was on the glass. Do appreciate the answers though. To describe the effect that dawn had I'll say this; If the water in your glass doesn't look like clear coat running down in perfect uniform, and makes small little droplets it is most likely the invisible residue from soaps. The clean glass seems to keep the surface tension of the water perfect so it acts like a full body of liquid the entire time it pours if that makes sense. It should not have little droplets all over the inside of the glass whatsoever. Makes drying a pain as well.
 
I (now) use Alconox cleaner. I got the tip from Sreetips and the stuff works beautifully. You can request samples from their website.
Alconox is a great glass cleaner (I’d buy some but I don’t need $20 worth of it) but it won’t remove the really stubborn stuff. Trying to clean organic round bottom glasses after some organic chemistry student confuses “gently warm over flame” with incinerate to slag inside the vessel! Fun times!
 
Fair enough Elemental! But, I think the company may have other cleaners for organic residues? Organics isn't really my wheelhouse and I have little experience other than cooking with them :) .
 
Well it’s been 20 years since I’ve had to clean any organic chemistry glassware like that. (Now I feel old) There are other solutions that work, such as piranha solution (works great on fritted glass filters) and a few other really nasty chemical combos (fuming acids) but sometimes the simple solution works best, which is why I like acid/base baths. It takes care of organics and metal salts really well. If you do a rinse afterwards with DI water you can get your glassware really clean with low effort.

My undergraduate research was in mixed polar solvents and how solvent strengths changed for various ratios. This was used to guide keeping super-critical carbon dioxide in a super-critical state to help separate chiral organic molecules. (i.e. if you only needed one chiral form for a medicine after synthesis of both enantiomers mixed together). I needed ultra-pure solvents and squeaky clean glassware for my tests, thus my into to acid/base baths.

Elemental

Endnote: Piranha solution is really nasty stuff, I know a lot of our refining uses concentrated acids but that stuff is on another level, in my opinion.
 
Well it’s been 20 years since I’ve had to clean any organic chemistry glassware like that. (Now I feel old) There are other solutions that work, such as piranha solution (works great on fritted glass filters) and a few other really nasty chemical combos (fuming acids) but sometimes the simple solution works best, which is why I like acid/base baths. It takes care of organics and metal salts really well. If you do a rinse afterwards with DI water you can get your glassware really clean with low effort.

My undergraduate research was in mixed polar solvents and how solvent strengths changed for various ratios. This was used to guide keeping super-critical carbon dioxide in a super-critical state to help separate chiral organic molecules. (i.e. if you only needed one chiral form for a medicine after synthesis of both enantiomers mixed together). I needed ultra-pure solvents and squeaky clean glassware for my tests, thus my into to acid/base baths.

Elemental

Endnote: Piranha solution is really nasty stuff, I know a lot of our refining uses concentrated acids but that stuff is on another level, in my opinion.
Piranha solution literally turns anything carbon to ash then the H2O2 reacts, or (oxidizes?) the ash into CO2 leaving nothing left, but gasses, and more angry piranha solution. Stuff is literally the epitome of no joke haha. Fun to watch though!
 
Alconox is a great glass cleaner (I’d buy some but I don’t need $20 worth of it) but it won’t remove the really stubborn stuff. Trying to clean organic round bottom glasses after some organic chemistry student confuses “gently warm over flame” with incinerate to slag inside the vessel! Fun times!
i can very much relate :D as an organic chemistry PhD :D
interesting research you did. chemistry is very exhausting, but also very rewarding :) and with ee ratios and stuff, there is always pain with analytics, posh appertures for polarimetry, posh chiral columns... yet in the middle of Europe, we dont simply have enough money for this stuff on university...

my routine for cleaning dont rely that much on removing the trace impurities (if one dont currently work with some Pd or Cu coupling reactions...), but purity of solvents is determinal for successful chromatographic separations. so yeah, distilling, distilling, distilling :)
our glassware cleaner is mostly acetone, easy to reuse (dont form azeotrope with water, and have low boiling point = short column and for one shot you have 95% stuff back for reuse). also acetone wash is often very much suitable substitute for dH2O wash. evaporates very quickly, washes all water away, so nearly any salts left from tap water. you certainly know all this, but for other folks maybe good tip :)

piranha for cleaning the fritted glass is very good idea. i always used nitric or DMSO/HCl... but i have some really dirty ones, sooo, big cleaning of lab before christmas is coming... now i know what i try to do :D
 
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