A new process developed by Georgia Tech faculty member Jeff Hsieh has successfully treated deinking filtrate without the use of chemical additives to reduce the amount of pigmented injet ink in the filtrate. Traditional flotation inkjet deinking has not been successful due to the hydrophilic nature as well as the submicron size of the pigmented ink that is generally used. Although many techniques have been researched to remedy this issue, they require large amounts of chemical additives, such as coagulants and flocculants, and are only able to remove small amounts of the inkjet ink while causing increased yield losses. The technique that was developed uses liquid-phase plasma along with a separating element (filter or settling or flotation tank) to effectively remove pigmented ink without the use of chemicals. This effect can be seen in the picture above which shows from left to right: a 0.6 g/L ink solution, the same ink solution after filtration, and the ink solution after treatment and filtering. This can also be seen in the figure on the right, which shows a pigmented ink solution forming visible ink particles floating to the surface of the solution. An additional advantage of this process is that the plasma acts as an initiator for polymerization of the ink particles, which allows the power requirements of the process to be greatly reduced. With the further development of this technology, the deinkability of pigmented inkjet inks can be greatly impacted. In addition, this emerging technology can be used to remove other micro-size particles, such as wax, slime, pitches, and micro-stickies.