Refinery
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How to handle powders without dusting?
How do you handle powders so that dust formation is minimized or at best eliminated?
A few methods come to mind, the obvious being to wetten the powder first, but obviously this is not an option in many instances.
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Belowzero
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Perhaps not directly answering the question but I use a glove box for especially toxic or very freefloating substances such as Al dust.
Simply made from a large plastic storage container with 2 holes in the side.
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Sulaiman
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Avoid creating static electricity, neutralise it if possible.
e.g. I believe that a member here had significant problems when working with a powder on a ptfe surface.
CAUTION : Hobby Chemist, not Professional or even Amateur
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Syn the Sizer
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Quote: Originally posted by Sulaiman  | Avoid creating static electricity, neutralise it if possible.
e.g. I believe that a member here had significant problems when working with a powder on a ptfe surface. |
I wonder if having and electronics ESD mat and Wrist Strap would help with this. They plug into the ground of your electrical system and discharge all
static electricity. When I worked for Vecima Networks here we built electronics for the telecommunications industry and we were not even allowed on
the assembly floor without our wrist and heel straps on and not into the production area until we tested the straps. I still to this day at my
electronics bench have an ESD mat and wrist strap.
Even if it is a small square 30cmx30cm, that's lots of room to deal with reagents of concern. You also want a wrist strap too, you want to be at the
same potential as the mat or you risk the reagent electrically clinging to you and your clothes
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Pumukli
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Static charge is a nuissance when it comes to fine powders which are non conductive! (Well, maybe even the conductive ones could be tricky, I never
handled them.)
In my experience a dry powder can badly dust if is stored in a non-conductive container (plastic or glass) and/or handled by a non-conductive
spatula/spoon/whatever!
For this reason, working on a grounded ESD mat alone is not a safe solution, conductive containers and conductive (not necessarily metal)
spoons/equipment would also be needed.
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Syn the Sizer
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That makes sense. There are conductive polymers which may resist corrosion more than metal which could help.
When building electronics we had 2 types of ESD bags, static shielding and static dissipating. We would store boards being worked on in dissipating
bags set in dissipating boxes on grounded shelves so the boards in the bag were at the same potential as us and the mat when pulled out of the bag.
The theory was that if the board had any potential in it when pulled out of a shielding bag it could discharge too quickly upon touching a grounded
surface and damage the sensitive ICs. They never considered the 1M ohm resistor on ESD equipment.
If static is an issue with dry powders, dissipating with with some form of grounded surface would help. Store dry powders in dissipating containers
and set them on an ESD surface for a little bit to dissipate the static charge before use, use conductive polymer scoops for such products.
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Fyndium
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I had a huge issue with packing some powders recently - static electricity. The stuff literally bounced around and my table was all mess after that.
What are efficient methods at neutralizing static electricity, if the formation of it has already happened or cannot be unavoided? Industry uses
grounded appliances, and they ground even the drums and vessels to the device to avoid staticity and sparking(Ex risk).
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j_sum1
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I have this bad habit of shaking containers to see how full they are before I open them.
Don't do that. 
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Twospoons
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| Quote: Originally posted by Fyndium |
What are efficient methods at neutralizing static electricity, if the formation of it has already happened or cannot be unavoided?
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Air ionisers are the usual method - usually balanced negative and positive ions. The ions are attracted to oppositely charged objects, neutralizing
the charge.
examples
Helicopter: "helico" -> spiral, "pter" -> with wings
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