Cant get solution to filter. MCT oil / Vac pump

superbane

Member
I’m posting this because a few of you may have perspective on the issue and I would like to solve the problem as quickly as possible lol

The following is from a conversation I’ve been having with daylight driller.

I guess I should state this before I go further. I have a Buchner setup. Anyways here goes:


I feel dumb as hell sending this message but I’m in a jam and really do need help.

I got 200ml of tren/test/mast I need to filter.
It’s 5% overdosed. 75mg each compound per ml. MCT oil. (This has held steady and is fine)

I have a 2.5 can vac pump
I used ptfe support screen gaskets to shim up the stainless steel support screen.

I have tried both 0.22 and 0.1 millipore pvdf filters. (I got the .22 after the suggestion of DD because filtering through the 0.1 was hours for 10ml)

I just tried to filter with the 0.22 and it literally would not filter warm oil. The oil just sat on top of the filter. It saturated but it would not filter through.

I thought perhaps I had ruined the filter in the autoclave so I tried a fresh one that wasn’t autoclaved and yielded the same results.

The vac pump was maxed out and started collapsing the hose. (Hose 5/16” ID x 7/16” OD - 50psi)

If I lifted the filter off of the stainless steel support ever so slightly I would get vacuum. So the filter was acting like a stopper.
Not even drops.

Pvdf filters.
Millipore gvwp 04700 - .22
Durapore vvlp04700 - .1

I’m at a dead end and do not know what to do? Clearly I am overlooking something.
 
Also before anyone suggests too much compound per ml or anything along those lines.

It does the same thing with just plain “Now Mct Oil”
 
can you take pictures of the setup?and link to the filter? Shouldn't need to max out either I only use a hand pump and with only 2 or 3 squeezes it will start coming throw slowly but still comes throw. Only 2 things it can be the filter or its not getting the suction to pull it throw.With pictures could maybe tell you witch one it is. But am pretty sure its going to be something with the suction. Without seeing it I would bet money on the fact its not getting suction throw the filter because it would burst the filter before your hose collapses like you said . I can say this with experience of being impatient =D
 
can you take pictures of the setup?and link to the filter? Shouldn't need to max out either I only use a hand pump and with only 2 or 3 squeezes it will start coming throw slowly but still comes throw. Only 2 things it can be the filter or its not getting the suction to pull it throw.With pictures could maybe tell you witch one it is. But am pretty sure its going to be something with the suction. Without seeing it I would bet money on the fact its not getting suction throw the filter because it would burst the filter before your hose collapses like you said . I can say this with experience of being impatient =D

I can’t take a picture of the setup at the moment but it’s the standard two piece Buchner with clamp set up.

upload_2018-8-10_10-57-16.jpeg
Similar setup

Fisherbrand Glass Microanalysis Vacuum Filter Holders - Filtration, Filter Holders and Hardware

Filters are
http://www.emdmillipore.com/US/en/product/Durapore-Membrane-Filter-0.22m,MM_NF-GVWP04700

I get plenty of suction if I pull the filter off the stainless steel support.
Or if the stainless steel support isn’t shim properly to create a perfect seal there is plenty vacuum to pull the solution around the filter through the leak.

Sealed and set up properly the filter acts as a damn plug :facepalm:

I’m going to get a hose with a thicker OD

Also going to clave a few more filters and check and see orientation.

Outside of these two things I’m at a dead stop.

I realize not really anyone used these setups.
I just liked the idea because of less consumables.

If I can’t figure it out I suppose I will just go to a bottletop!

Thanks for the response though.
 
I can’t take a picture of the setup at the moment but it’s the standard two piece Buchner with clamp set up.

View attachment 95665
Similar setup

Fisherbrand Glass Microanalysis Vacuum Filter Holders - Filtration, Filter Holders and Hardware

Filters are
http://www.emdmillipore.com/US/en/product/Durapore-Membrane-Filter-0.22m,MM_NF-GVWP04700

I get plenty of suction if I pull the filter off the stainless steel support.
Or if the stainless steel support isn’t shim properly to create a perfect seal there is plenty vacuum to pull the solution around the filter through the leak.

Sealed and set up properly the filter acts as a damn plug :facepalm:

I’m going to get a hose with a thicker OD

Also going to clave a few more filters and check and see orientation.

Outside of these two things I’m at a dead stop.

I realize not really anyone used these setups.
I just liked the idea because of less consumables.

If I can’t figure it out I suppose I will just go to a bottletop!

Thanks for the response though.
I get what your saying but the vacuum would burst the filter before it damaged the hoses is what am trying to get at I cant see it being anything to do with the hoses. Why the 2 piece setup though have you tried just 1? do you need the 2?Something might be acting as a plug but it wont be the filter. have you tried taking the filter of and placing your finger ontop of the blue bit to make sure its got good vacuum there?if it does I can only imagine its losing its vacuum at the clamp that's holding the beaker thing onto it.Read the home brew sticky forum about unsterile filters I just run some ba throw them and it works perfect but suppose if you got a clave wont do any harm. Just don't exceed the max temp.
 
If it's collasping the hose, there's plenty of vacuum. Have you tried pulling straight water? You've used the set up before right?

I use a hand pump and everything has to be set up just so...or it won't draw. If the hose is collaspsing there's vac at the base of the filter for sure.
 
Do the filters have to be pre lubed? Primed almost? I think I've heard people talk about that being an issue but I've always used bottle top units, so no first hand experience
 
No i have a single flask setup.
There is definitely vacuum in the base.
If I pull the filter paper off of the support screen. The vacuum will rush water right through put the filter over the support screen it acts like a plug.

I pulled the stainless steel support screen out and just tried the filter paper. The vacuum pops or splits the filter paper.
So I have a few ideas.

Going to keep at this shit until I get a working unit.

Icky I believe you are thinking of hydrophobic filters the ones I have are hydrophilic.
 
Whatever the problem is has to do with the stainless steel support I don’t get it because it is a screen really and the holes in the mesh are clearly bigger than the filter but :Shrugs:
Whatever that particular part was a replacement part and did not come with the unit when purchased. Going to have to track down another one and try it again at a different point in time.

Switched over to a polysylfone filter holder and base and boom everything works as it should.

Pretty damn strange.
The difference aside from the plastic vs glass is the poly has a ptfe support not a stainless steel.

I don’t know but it works and I’m thrilled.
Thanks for you guys throwing out ideas trying to help, lol I didn’t feel so alone in the dark!

Ordered some bottle top filters too just Incase if emergency lol
 
Good luck man. If I ever start brewing in volume again I'm going to get a set up like you have. Would rather have little disposable filters.
 
Glad you got it sorted man. What was the price of the setup? I looked at getting it before but couldn't find the filters so I just ordered a box of bottle tops =D but I was still just going to use the hand pump I don't mind the hand pump tbh =D
 
Glad you got it sorted man. What was the price of the setup? I looked at getting it before but couldn't find the filters so I just ordered a box of bottle tops =D but I was still just going to use the hand pump I don't mind the hand pump tbh =D

I can’t give you an exact price I pieced it together over time. Snagged part of the setup off of eBay hence where the problem arouse from finding that replacement piece.

Daylight driller told me about the filters.
They came out to about a $1 a piece.
You could always use nylon if you aren’t using super solvents. They are cheaper.
Going to need an autoclave to sterilize the filters. Unless you were to buy the individually sealed pre sterilized ones.

Glass funnel / base / clamp
Filters
A filter flask
No.8 stopper
Hose
Psi/mg gauge (for pulling).
Vac pump.
Autoclave or sterilized filters.

These setups come in 25mm 47mm and 90mm

I’ve seen Chinese kits on eBay and Amazon for around 100

@picholas just posted a similar setup in the brewporn thread.
I know daylight driller and burymebig both used Buchner as well.
 
I did mine much the same way. Grabbed items when I saw a good deal on ebay or craigslist. I actually still use the hand pump with my set-up. Eventually I'll get an electric set-up. No rush, just slowly building a nicer set up.
 
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