Wow, just wow... That is thinking outside the box... err cartridge. Why? Is re-inventing the wheel a personal hobby? Do you have the monetary resources to experiment with what particulates will reliably pass through X printhead? Have you already figured out what type of carrier will keep the pigment particulates in suspension and not settle to the bottom of the printhead and totally clog it up?
Since you are into experimenting, how about using "powder coating" powder to run through print heads. I'll bet there would be a market for that! Liquid Powder Concepts
sells a carrier for powder to spray powder coating via a liquid carrier. Maybe you could start there.