Sciencemadness Discussion Board

Washing and storing glassware.

evil_lurker - 15-3-2008 at 11:57

Ok so I'm doing some post whoring and wanting to start a discussion on washing glassware.

I hate washing glassware after a reaction... to me thats more of a PITA than pulling off most reactions.

Makes me nervous to hold something thats worth several hundred dollars, extemely easy to break, and slippy on top of everything.

Anyone ever have a permanent soak tub that they put their glassware in?

And why do condensers seem to always want to cloud up on the coolant path?

And why the heck can't you seem to never clean them up?

How do you store your glassware?

What do you do with bulky items such as condensers and what not?

Any tips would be appreciated.

[Edited on 15-3-2008 by evil_lurker]

12AX7 - 15-3-2008 at 12:02

Soak tubs are for cleaning things, like a soak in detergent and whatever else goes in there (the school lab has a soak container with some stuff in it).

After a reaction, you naturally swirl with a few squirts of distilled H2O, that should be rather easy to you by now.

Condensers get cloudy in the jacket due to minerals in the water (dependong on geology). Wash with mild acid every once in a while.

Quote:
And why the heck can't you seem to never clean them up?


So you can clean them? Then why ask?

I'll tell you how I store my condenser when I get one. :P

Tim

P.S. Would this be better suited to Apparatus or Misc.?

bfesser - 15-3-2008 at 12:41

For condensers, a standard workshop toolbox and some bubble wrap would probably be a good way to store them (could also throw pipettes in the top tray, stoppers, adapters, or thermometers maybe), if you don't just buy an organic kit in a case.

To make this quick, any advice I can think of right now:
<ol type="1">
<li><underline>always</underline> wash immediately after reactions, don't be lazy or you'll pay for it later</li>
<li>always rinse with distilled H<sub>2</sub>O (I habitually rinse inside cooling jackets, even.)</li>
<li>hold expensive glassware as low in the sink as possible, so if it drops, you might just get lucky and it'll bounce... you could also consider getting a rubber pad or something to put in the bottom of the sink</li>
<li>if you have a small sink with a low faucet like mine, get an adapter to connect a flimsy rubber hose to it, and use that to wash difficult items like burets and other large apparatus</li>
<li>cover flask openings with aluminum foil after they're completely dry to keep out dust during storage, it saves time and water, but try to recycle the foil whenever possible</li>
<li>don't throw away old toothbrushes, and use lots of bubble-wrap</li>
</ol>

Magpie - 15-3-2008 at 13:16

Here's how I do it:

1. If I have a sticky residue I get after it right away before it sets up. This might include a presoak in hot soapy (detergent) water or an appropriate solvent.

2. Other wise I just place everything in the sink with hot soapy water and let soak overnight. Rinse the next day with warm tap water and let air dry for a while, then wipe dry with a towel. I have fairly soft water so don't bother to rinse with distilled water. Nor do I get any residue in the coolant side of my condenser. :D

3. I place all of my beakers, flasks, and grad cylinders in the cabinets. The complex, delicate glassware I place carefully in a drawer. I've lined my drawers with the perforated flimsy rubber mats made for kitchen drawers. They are cheap and readily available.

evil_lurker - 15-3-2008 at 14:33

For general all around detergents I prefer Alconox and "Mean Green" degreaser.

For removing TCCA off of glass nothing beats hot lye solution.

For removing high vacuum grease off of glassware, I've found that starter fluid and toluene works pretty good, but will require some scrubbing. Haven't tried acetone or MEK yet but I bet they would be great. Lye also seems to help out too.

I use RO/DI water for my rinse. Nice, cheap, and an almost unlimited supply. Doesn't leave a spot anywhere.

For storage, I use metal/wood shelves instead of drawers due to lack of drawers and cabinets. I try to store my "widgets" and adapters in the necks of the flasks to keep them from going everywhere. Also have a baby bottle drying rack that I store widgets on.

grind - 15-3-2008 at 16:08

Quote:
For removing high vacuum grease off of glassware, I've found that starter fluid and toluene works pretty good, but will require some scrubbing.

You can use water soluble grease (glycerine + soluble starch). It has the advantage of not being dissolved by most solvents, so you never again will find that shit in your products. You can use it for high vacuum applications too. Cleaning is extremely easy - washing down with water.

BromicAcid - 15-3-2008 at 16:24

Bfesser has the best advice of the lot in my opinion. One related issue is that I have been told my glassware should not be stored so that it is touching, that each time two pieces of glassware bump together it causes damage, even if it is invisible. Don't know how true it is but I stopped stacking my glassware in drawers after that.

Best is to have rubber and cork rings to set out your flasks so they're all given their own space. Keep them in drawers if possible so they don't go rolling off shelves. And as Bfesser said, clean glassware immediately after use. And once clean use aluminum foil to cover necks to keep the inside clean.

Condensers in my area turn red on the inside from bacteria in the water, hydrochloric acid takes this out well enough, also works on calcium deposits. Basically set up a condenser and lead one inlet into some HCl solution and pull a vacuum on the other side, best bet is into a Erlenmeyer with a side arm so you don't pull the solution into your vacuum source. Takes a few runs but I have had excellent results with this.

Misc. glassware goes well in a drawer too, pieces of cardboard do well to separate it, some cardboard with some duct tape can make a whole customized drawer that looks great and stores everything for quick use.

And one last note, think about how you are going to clean your glassware before you even start a reaction. You think about where you are going to get your reagents, how you are going to run the reaction, how you are going to do your workup and waste disposal (hopefully) so just add in how you are going to clean your glassare. Otherwise you might do a reaction that ruins your glassware. I did this while trying to make CS<sub>2</sub> and got some horrific charcoal/sulfur mixture stuck in my flask, if I'd thought about the kind of cleaning that I would have had to do at the end I might have been more reluctant to give it a try.

vulture - 15-3-2008 at 16:47

Acetone, acetone, acetone. If that doesn't work, chloroform, then hot chloroform (or DCM), finally aqua regia or HF (god forbid).

azo - 15-3-2008 at 18:19

The best way to clean glasswear i find is to put a small amount of conc sulphuric acid in and swirl untill all the glass is covered this will destroy any unwanted organic contaminents then wash thourougly with water and rewash with a strong sodium hydroxide solution followed by washing with a neutral detergent like dishwash liquide ;)

evil_lurker - 15-3-2008 at 18:24

Concentrated sulfuric is not the best thing to be used on glassware... actually it doesn't hurt the glass, but if you spill it you could possibly be in for some very nasty burns and possibly a trip to the ER if it splashes on you.

Same thing goes for the hydroxide.

I'm not for sure if its a "rule" per se, but I always use the mildest cleaner that will get the job done and if it doesn't I work my way on up.

cleaning glasswear

azo - 15-3-2008 at 18:34

of course you need to be carefull when using strong acids and bases i always wear glasses.
and make shaw that there is a water source close incase it drops on me or do what i dont do and use impervious gloves
anyway if you dont have experience with handling strong bases and acids you shouldn't be doing it.:D

The_Davster - 15-3-2008 at 18:51

At home, I buy distilled water, so my washing is done with tap water. If I am doing something sensitive to contaminant ions from the hardness in the water, only then do I wash with distilled before use. Appropriate acids/bases to clean what does not come off, depending on what is present.
I store my ground glass apparatus in a drawer full of packing peanuts, beakers are just stored upside down, as are flasks.

I was unaware of the issue of glass just touching, so I am going to rearrange a few things after this post.

At the lab in university, we always wash with distilled first, then soaked in KOH/alcohol overnight, then a distilled wash again, followed by HCl solution overnight, followed by a final distilled water wash. The glass comes out looking good as new, but the graduation marks on beakers and graduated cylinders fade over time.
We have large tubs for the acid and base soaking solutions

[Edited on 15-3-2008 by The_Davster]

bfesser - 15-3-2008 at 18:57

I forgot to mention one very important thing in my earlier reply. It's usually a bad idea to store any ground glass joints assembled, unless, of course, you're storing a reagent in a stoppered bottle. A little bump and they tend to stick together. If you've never had to unfreeze a ground glass connection, you're in for a treat. There's lots of methods... the downloadable Chemglass catalog has a pretty comprehensive section detailing different tricks to do this.

Quote:
Originally posted by BromicAcidOne related issue is that I have been told my glassware should not be stored so that it is touching, that each time two pieces of glassware bump together it causes damage, even if it is invisible. Don't know how true it is but I stopped stacking my glassware in drawers after that.

I think you're being overly paranoid. ;) What do you do when crystals don't form after cooling during a recrystallization (besides adding a seed crystal)? You scratch the inside of the flask with a glass rod. Unless you're using vacuum and you see star cracks, you probably have nothing to worry about.


One last comment; acetone works wonders, but if kitchen dish detergent and tap water will work as well, use it, it's cheaper.

[Edited on 3/15/08 by bfesser]

cleaning glass

chemrox - 16-3-2008 at 00:43

I'm haveing a hard time getting my glass clean after some of the work with vegetable oils and low MW aliphatic acids. Chromic acid just isn't doing it and sometimes makes it worse. Pirhana needs to be freshly made as I undertand it so that's a big cost of I have to resort to it too often. Strong base is to be avoided as it removes glass. Sometimes I resort to long visits to the oven. BTW- the notion that glass touching glass causes damage is nonsense. CAUTION: always grease or tape those joints well-I have a stuck joint tying up my long Snyder column and so far everyting I've tried has failed. "Chemglass" catalog you say?

Davester: get us the specs on those soaking solutions will you please?

[Edited on 16-3-2008 by chemrox]

azo - 16-3-2008 at 02:58

chemrox you can heat the outside glass rapidly with a propane burner this will exspand the glass enough to come out

always use joint grease

bfesser - 16-3-2008 at 06:01

Sorry, my memory failed me. The catalog was Ace Glass, not Chemglass...

Unfreezing Joints:
http://www.aceglass.com/html/2008/pdf/index.php?page=16
(I guess it wasn't as good as I remembered it to be...)

Perhaps more useful; resin codes & compatabilities:
http://www.aceglass.com/html/2008/pdf/index.php?page=13

I sometimes succeed with hot water on the outside joint and cold water on the inside joint. Soaking in isopropanol has worked for me, as well. But stuck joints are the reason I prefer hollow penny head stoppers. If the stopper gets stuck in an expensive apparatus, you can just take a diamond file and score around the penny head, snap it off, and use a nail with a hammer to hit the inside bottom of the stopper and break it out piece by piece. They're usually a lot cheaper than whatever they're stuck in. Ultrasonic cleaning baths are supposed to work wonders (for stuck joints and residues). Has anyone tried one?

[edit]
Pages 14-15 of the Ace catalog have cleaning tips.

[Edited on 3/16/08 by bfesser]

MagicJigPipe - 16-3-2008 at 06:57

I always use distilled water just because it's cheap and easy. I used to have a dedicated distillation rig just for making distilled water. It consisted of a neon glass tube running from a large stainless steel pot. The jacket was a pvc tube covering the glass and seeled with caulk around it. From there it would drip into a 5 gallon bucket (thourougly cleaned). Then I had a water pump that would pump the water into a larger 25 gallon tank hanging from the ceiling so I essentially had unlimited distilled water that had almost as much pressure as the tap. Of course I never used it for and aspirator but it was used for just about everything else. It cost about $50 but I'm sure (if I still had it) that it would have paid for itself eventually (unless the energy use would make it more expensive; natural gas) by not having to buy distilled water.

Also, I usually boiled the water for a minute before distilling to expell any gases.

Anyway, my point is, I think it's a good idea to just get in the habit of using distilled water for everything. It can't hurt.

I would only use xOH to clean glass as a last resort. And about using concentrated acids, if you are scared to simply clean your glassware with H2SO4, then how do you use it in the lab in large quantities? Always wear protective equipment and buy one of those eyewash stations you can connect to a faucet and you'll be fine.

grind - 17-3-2008 at 16:59

A good method to unfreeze joints, for example a flask with a cooler:
Place the joints beneath the surface of diluted HCl and then make a vacuum inside the whole (empty) apparatus. The HCl is sucked between the joints. When the joints are completely wetted, remove the apparatus from the bath. Clean the outside with water. Now you can heat the joint connection in the usual way. That works in the most cases.

Klute - 18-3-2008 at 09:58

I personally use a base bath for all my glassware, it works perfect. NaOH in EtOH, in a 30L tank, half full. I leave the glassware in there overnight, and the next day transfert it to a another tube full of water, and rinse it genrously under the tap. Removes nearly evryhting. The harder stains are dealt with by using longer soaking periods (too long and it can etch the glass, so beware. Never leave glass frit for more than 12H), or pirahna (which can be kept for at least a few weeks BTW, but represent a hasard: you don't want to knock it over! Obviously, no capping!).
Since I've made this base bath, I can't got back to scrubbing :). The bath needs changing only evry 6-12months, as it get dirtier and dirtier, and the hydroxide tunrs to carbonate.

IIRC, you dissolve 100n g of NaOH/KOH in 120n mL dH2O, then slowly add with stirring 1n L of denaturated EtOH. After a few hours, it starts getting brown/black from condensation of denaturants, not a problem. It doesn't look very pretty after a couple months of use :D. Remove all silicon grease and company, and most organic materials. It is obviously preferable to prerinse the glassware with acetone and remove most of the grease with some paper first. Just keept he tube well covered, and in a safe place. Use full face protection (the plastic screens that fit over your face), and thick neoprene gloves. If you don't wash the glassware within the few hours of placing it in the rinsing tube, some deposit can form. This is easily removed by adding a little acid to the water.