Given 1.0's addition of Alchemy this could be IC2's enhancement of it.
A Centrifuge is a more powerful Alchemy device, running it on its own will produce potions much faster than the basic device. However the Centrifuge can also be used to make Stims (an advanced potion) by using the various ingredients with an empty needle instead. These Stims are more potent and longer lasting than their basic potion ingredients, by extension you can also create Grenades instead of Splash potions, which are more powerful versions of the Splash Potions made using a Grenade Case and the various ingredients.
Needles are created using metal, glass, and rubber and are placed into the container slot of the Centrifuge in combination with the ingredients, Grenades are created using a Grenade Case in the slot for the bottle and the splash potion ingredients at the top of the UI. Power is required to run the Centrifuge (of course).
Empty Needle
-G-
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G = Glass
Grenade Case
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