[BillM]

I came across some military silica dessicant bags recently,they're from some time
in the '70s,were packed with artillery shells as I understand.My question is...
can these things be "recharged",dried in a microwave to prolong use,life?

[lithos]

The ones I've used turn pink or blue or some other colour when the dessicant gets saturated.

I had some I bought from a camera store. The recommendation was to dry them out in a very slow oven (100 degrees C/212 F) until the colour faded and they went back to white/clear. So, think of it more as "decharging" rather than "recharging."

I'd go the oven route, rather than the microwave. For starters, there might be metal hidden somewhere in the bags.

Secondly, I've no idea what would happen if put silica in a microwave. Since microwaves directly excite the water atoms, rather than heating everything up (ie, they work backwards,) the crystal might explode or something.

Thirdly, the oven's a lot gentle, and it'll take longer, so you can monitor what's happening. Also, since there may be steam, given the tiny size of microwaves, there's a good chance of getting a lot of it reabsorbed.

[Russell-Evans]

I came across some military silica dessicant bags recently, they're from some time in the '70s,were packed with artillery shells

I'd go the oven route, rather than the microwave.

Four decade old military goods is a lot of unknown history. The 70's were the era of agent orange, DDT, black ops biologic and chemical weapons, ... and you want to throw them in the oven/microwave? I'm not sure I would even bring them in the house.

Thank you
Russell

[GerryL]

Silica gels are actually cheap to buy so, it would be better to acquire new ones than take your chance on those old ones.
If they were kinda expensive, then I would understand your interest in them.
Silica gels are easily available and very east to acquire.

[BillM]

I think your imagination getting the better of ya russ They were the best price
availible,free, the size and manner in which they're packaged piced my interest.
app. 4 inches square by 3/4 inch deep, in cotton. Wicks are sewn around edges
in same manner native americans fabicated garments,serves same purpose.
pretty fancy,real cheap, could'nt resist .I trust most these dealers less than
the military. thanks guys.