I have great difficulties moving very fine powders from a drying dish (glass) into small plastic containers using a metallic spatula due static charging. I have to scratch a lot inside the glass beaker to get all the powder together, I guess that the charge builds up that way. When I lift the powder out, the majority or even everything on the spatula flies off to stick to the glass. Due to lab safety I also wear nitrile gloves if that is important.

I want to order better equipment now so that I do not have to combat static charges. I will order plastic single-use spatulas - advertised as anti-static - and some new evaporation dishes. But there is no indication in the webshop, which material might be suitable for that. I can select from porcellain or the plastics PTFE and PFA. There are some anti-static weighing dishes, but they are made from PS and very lightweight, and can thus not hold acetone or ethanol, which is a requirement.

So I am stuck with the question, which material should I choose for the new evaporation dishes?

Edit to answer the comment: The powder, typically less than 100 mg, is washed into the evaporation dish with either acetone or ethanol. When the powder is completely dried it is transferred into a small plastic container. The Aluminium foil would be an option, but Platinum is a bit too expensive for this purpose.

  • 1
    $\begingroup$ Gloves are causing this static build up. Can you keep the beaker on a conductor like a aluminum foil? And frequently discharge the spatula by touching the Al sheet. Add more details to clarify your question. How much volumes are you talking about? What solvents are present? If the department can afford, there are platinum evaporating dishes. $\endgroup$
    – ACR
    Commented Dec 16, 2021 at 14:00
  • $\begingroup$ Depending on the chemistry (solvent to evaporate, sample per se, mass and volume to carry), metal dishes made out of aluminum may be suitable and less expensive than those out of Pt (example 1. example 2), too. For sand baths under the hood, the stainless steel variant (example) work well, too. $\endgroup$
    – Buttonwood
    Commented Dec 16, 2021 at 14:33
  • $\begingroup$ Depending on the hazard you can remove the gloves. I mean just for that transfer operation, especially if it is done in a very clean corner of the lab (scale room, preparation room, etc.) $\endgroup$
    – Alchimista
    Commented Dec 17, 2021 at 9:02
  • $\begingroup$ Thanks for this question as static electric charges are largely ignored, while unlike photo/sunlight, the latter effects are well known. A major exception being, of course, when a static induced charges creates an explosion (for example with N2O which is not especially photo sensitive). $\endgroup$
    – AJKOER
    Commented Dec 17, 2021 at 16:07
  • 2
    $\begingroup$ Definitely don't opt for fluorinated polymers (PTFE, PFA) as they are one of the best materials for collecting the charge. $\endgroup$
    – Pepsi-Joe
    Commented Dec 19, 2021 at 4:39


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