Sciencemadness Discussion Board

Screwed soap cleaning soln, how to proceed?

DrScrabs - 11-5-2019 at 06:10

Hello everyone!

So I wanted to give my glassware a nice soap bath today to remove some sticky goo wich, luckily, really dissolves in soapy water and didn´t have any non parfumed soap on hand so I decided to "quickly" hydrolyse some rapeseed oil.
I made an excess of conc NaOH soln and dumped in the oil with vigorous stirring @70°C for about 8h (done over the night). I expected the conversion to be complete and dumped the soap suspension on the glassware in a plastic container and filled it with warm water.
Unfortunately there was way more unreacted oil than I have ever experienced. The total amount of oil would make solvent cleaning afterwards the most costly ever!

Now every piece of glass has a "nice" oil coating an there´s plenty of it floating on the top. I don´t want to add more Na/KOH to keep my perfectly fitting joints alive but want to get rid of the oil of course.

My next thought is to add aq. ammonia to hydrolyse the remaining oil over the next days but wanted to ask if anyone got a better idea how to deal with this situation.

Thank you very much and have a nice weekend,
DrScrabs

[Edited on 11-5-2019 by DrScrabs]

CobaltChloride - 11-5-2019 at 07:23

As far as I know, soap with perfume works perfectly well for glassware as well as long as it's for cleaning dishes and not hands or clothing since those soaps might contain hydrating oils or perfumes made to stick around respectively.

I don't think it was neccesarily required to make some soap yourself. You can try letting the glassware sit for a long time in a Na3PO4 solution since it is strong enough of a base to hydrolyze oils. Another option it just scrubbing with dish soap.

DrScrabs - 11-5-2019 at 08:27

Thanks, the last time I used perfumed soap I had problems removing it, maybe it was the reason you mentioned, I did not know about that!
I am looking for a one pot solution to save the work ;) sadly I dont hace any Na3PO4.
I will try ammonia, I think it will hydrolyse the most of the oil within the next days as I am a bit lazy. I´ll give an update though.

SWIM - 11-5-2019 at 09:33

To deal with stubborn oils or greases scrub them with dishwashing liquid without water.

Just wet the flask and pour the water out, then add a crapload of dishwashing liquid undiliuted.

Scrub it with that and the oils are broken up quickly and easily.
The resulting emulsion washes out well with water.
This can also be helpful with adhesive residue on flasks that had tape on them, and for getting stubborn marker stains off your glassware.

I picked this up working on cars.
Somebody showed me that straight dishwashing liquid breaks up the heavy black grease you get on your hands working on dirty old cars and I later started using the trick on glasssware.

A strong solution of the powdered detergent they use in automatic dishwashers works pretty well too.
I use Cascade (A US product for home use) for general glassware cleaning and soaking and other home chemists I know speak highly of it as well.

CobaltChloride - 11-5-2019 at 10:49

Melamine sponges are also great for removing seemingly impossible to remove stains on glassware. I had some polymerized sunflower oil hard chunks on the bottom of a flask after heating it in a sunflower oil bath for a long time and the only way I found to remove them was scrubbing with a moist melamine sponge.

unionised - 11-5-2019 at 11:19

You are seeking to remove fat from glassware.
How is that different from "washing the dishes"?

Stop moaning, roll up your sleeves and wash up

fusso - 11-5-2019 at 11:50

Piranha soln? My fav glass cleaning soln!

DrScrabs - 11-5-2019 at 12:01

I am not seeking to remove the oil, I am a bit lazy atm and combined with a lot of time I expect to handle it chemically!
Washing the glassware by hand takes A LOT OF TIME to get rid of every bit of oil. I am on the road for the next days so soaking it in NH3 sonl is way better for me IMHO than coming back and still having to clean every little shit part.
As I mentioned every mm² is covered in oil, hydrolysing is much more simple if you have time.

Piranha is top of course, but as I have only acess to 12% H2O2 it´s quite a bit weaker an also not really suitable for this amount of shit. Also it may produces some carbon stains or some other byproducts etc.

I´ll stay with ammonia, cheap and easy.

Update anyway!

ficolas - 11-5-2019 at 14:23

What about washing with an organic solvent?
Just gasoline maybe, its pretty cheap for chemistry.

RedDwarf - 11-5-2019 at 16:18

Don't you have a dishwasher? Either an electro-mechanical one or one of the older biological versions? :)

unionised - 12-5-2019 at 00:50

Quote: Originally posted by DrScrabs  
I am on the road for the next days so soaking it in NH3 sonl is way better for me IMHO than coming back and still having to clean every little shit part....

I´ll stay with ammonia, cheap and easy.

Update anyway!

Enjoy your trip.
Let us know how your voyage of discovery goes.
(The one where you discover that ammonia is a rather weak base).

Tsjerk - 12-5-2019 at 01:21

Ammonia is perfect for cleaning greases, put your stuff in a plastic bag, poor in some 5% ammonia, close it and wait for a day. Afterwards you can rinse with warm water and everything is clean as a whistle.
Ammonia had the benefit it fumes, so you don't even have to cover everything, as long as everything is a bit wet with water you only need a bottom of ammonia. I used to do this with my deep-fryer parts.

DrScrabs - 14-5-2019 at 05:15

@ficolas gasoline has so many different additives, also to get rid of it and the fire hazard are sth I want to avoid.

@RedDwarf a dishwasher is a good idea but I lately used my glassware in an experiment in wich pharmacuticals like beta carboline can be present in significant amounts, nothing I want in my dishwasher and I don´t have one for chemistry.
Also the synth had toxic substances as precursors. I prefer to use the tub I dedicated for that use :)

So far the ammonia does a good job.
I discarded the floating grease and added 500ml of 10% household ammonia to the about 35 or 40l of soapy water and let it sit for maybe two or three more days :). The glassware was still a bit covered in oil but not as much as before.

DrScrabs - 16-5-2019 at 08:41

So I discarded the cleaning sol and the result was awful. All my glassware is now covered in a thin layer of whatever, dirtier and worse than before.
I have to scrub it by hand now. Just don´t do what I did.
Maybe I´ll go with gasoline but I´d do that at the fuel station of my dad.

Ubya - 16-5-2019 at 09:06

Quote: Originally posted by unionised  
Quote: Originally posted by DrScrabs  
I am on the road for the next days so soaking it in NH3 sonl is way better for me IMHO than coming back and still having to clean every little shit part....

I´ll stay with ammonia, cheap and easy.

Update anyway!

Enjoy your trip.
Let us know how your voyage of discovery goes.
(The one where you discover that ammonia is a rather weak base).


Quote: Originally posted by DrScrabs  
So I discarded the cleaning sol and the result was awful. All my glassware is now covered in a thin layer of whatever, dirtier and worse than before.
I have to scrub it by hand now. Just don´t do what I did.
Maybe I´ll go with gasoline but I´d do that at the fuel station of my dad.


In the end scrabbing by hand is still needed

DrScrabs - 17-5-2019 at 13:08

Yes it is, used .5L of dish washing soap and a rinse with hot sulfuric acid followed by lots of dH2O and now it´s perfectly clean again!

I will never do sth like that again, for sure!

unionised - 17-5-2019 at 15:38

Quote: Originally posted by DrScrabs  
Yes it is, used .5L of dish washing soap and a rinse with hot sulfuric acid followed by lots of dH2O and now it´s perfectly clean again!

I will never do sth like that again, for sure!

So, in case anyone was wondering, yes, I'm enough of a git...
"
Enjoy your trip.
Let us know how your voyage of discovery goes.
(The one where you discover that ammonia is a rather weak base)."
"
You are seeking to remove fat from glassware.
How is that different from "washing the dishes"?

Stop moaning, roll up your sleeves and wash up"

SWIM - 18-5-2019 at 13:42

Quote: Originally posted by unionised  
Quote: Originally posted by DrScrabs  
Yes it is, used .5L of dish washing soap and a rinse with hot sulfuric acid followed by lots of dH2O and now it´s perfectly clean again!

I will never do sth like that again, for sure!

So, in case anyone was wondering, yes, I'm enough of a git...
"
Enjoy your trip.
Let us know how your voyage of discovery goes.
(The one where you discover that ammonia is a rather weak base)."
"
You are seeking to remove fat from glassware.
How is that different from "washing the dishes"?

Stop moaning, roll up your sleeves and wash up"



Perhaps at times; but you're a competent and extremely helpful git.
That makes all the difference.