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Hi all,

I need to make up some potassium permanganate, I have my printout for solutions that I got off this site and it says to "filter through glass wool".
Any other way of filtering it???????????????

Guidance will be much appreciated

Recipe in our book ( standard DOE recipe book ) doesn't mention filtering through glass wool or anything .........so I googled a bit as none of our other books mentioned it either .

Apparently you can't use filter paper because it is organic based and will be reacted by the KMnO4
Appears that the Glass wool filtering is done after boiling the solution for an hour or so and cooling to remove Manganese Dioxide impurities .
I saw mention of also using a Glass Crucible ...I guess they mean Sintered glass Crucible with vacuum pump in side arm flask setup/

Maybe it depends what its going to be used for whether you need to filter it or not .

LOL....at least I just worked out what the jar of Glass wool in the Chem store is used for

....and just how long has it been sitting in your Chem store with you wondering what the devil it's used for?

I used to use it to filter fish tank water years ago when I had smelly fish tanks and yabby tanks in the labs. Thank goodness we don't have them any more!!

Ha Ha bigmack! I'm glad I was able to solve a query for you!!
I did a bit of googling too and filtering wasn't mentioned anywhere else. So we'll see what happens!!
Thanks for the replies, people

Lyn wrote:....and just how long has it been sitting in your Chem store with you wondering what the devil it's used for?

I've worked in two different schools prior to this one and never opened the HUGE container of glass wool in either of them. Never knew what it was used for until now!

I know when started 13 years ago, the Chemistry teacher asked for wool glass. I didn't have any, so I ordered it, for next time. I've never been asked for it since.

There is none here..........that I have come across anyway, there are still corners of the storeroom I haven't delved into yet haha! It does seem though that glass wool is not a regularly used item.

I have a small quantity which rarely gets used. Although the Laboratory Manual by B. Dungey does mention using it for filtering potassium permanganate when you prepare a solution.
I get a little paranoid that one day some teacher is going to see the word wool ignore the fact that it has glass written in front of it and grab it to use for growing seeds. So I try to keep it in an out of the way place, usually top shelf at the back. Only problem is I forget it is there and only find it when I am trying to find some other elusive piece of equipment needed for something else.
Just as an afterthought - if you have access to fibreglass material you may be able to use that instead as a filter. Or do some trading with a lab tech who has jars of glass wool sitting around in their store room.

Lyn wrote:....and just how long has it been sitting in your Chem store with you wondering what the devil it's used for?

Sure did Lyn , but filtering never crossed my mind .

I,ve been here 3 years and only found it last year . By the dust and grime on the bottle , I'd say it gets used as often as the stuff the other :Labbies have .

I just had another look at it and there's a larger jar next to it with Low Lead glass wool on the label. Two types

Does anyone know how you filter with it ? How much , how compressed , can you wash it and reuse it ?

I used to put it in one of those tubes that you filter fish tank water through and pump the water through it. It would go green and slimy and I would throw it out. No question of reusing it.

Thanks J

We've just used glass wool in the heating solid potassium permanganate prac. It's placed at the end of the test tube to stop the solid particles flying out but lets the O2 out so you can reignite a glowing splint.

My question is, can it just go in the bin? Would it need to be wet first (according to google it's fibreglass) or is just wrapped up in some paper towel ok? Or should I just put it in with the manganese waste for disposal?

There are no instructions for disposal of fibreglass on RiskAssess (but it is listed under equipment), so I guess putting it in the bin is fine. It does say stuff about handling with gloves and masks. (Edit) Chemwatch says "Store in cool, dry, protected area. Dispose of this material and its container at hazardous or special waste collection point. Keep out of reach of children."