Vacuum flask and Buchner funnel usage

[youngleo]

I was thinking of using a vacuum flask and Buchner funnel for two things. Seperating the gold foil out of the AP solution; and seperating the gold precipitate from the SMB reaction. I have read the threads on the latter (thanks for the great posts to all) and understand that smaller is better and use a high quality filter paper (thanks harold). Any additional thoughts on that one? as well as the former? I was thinking that this might give a really good oportunity to wash the gold foil before dissolving it.

Here are my concerns.

1. Is the foil too dense? Will it just clog the filter paper and stop the suction through it?
(Perhaps a 150ml funnel and 4L flask are better suited)

2. Will the filter paper absorb the gold powder and cause an unacceptable amount of shrink?

Thanks for you help in advance.

Leonard

 

[samuel-a]

i don't use Vacuum filter at all, but foils will not clog the filter, unless very large amount.
gold powder and super fine foils will be catched in the filter.

in general, i would suggest that you should try to avoid putting the bulk of material (powder or foils) in the filter.
dissolve the gold in the same flask the you ware washing it.

the filter is just there to catch the floaters, so y'll save time without waiting for every thing to settle.
this gold in the filter you will recover later with the rest of the used filters.

i'm using settling tanks for my AP batches, that way, when filtering (either by Vacuum or gravity) your filter will last longer and will catch as less gold as possible.

good luck