Delayed Start

Electrodeionization (EDI) is the process of ion removal with the driving force being an electric current. When current is applied, ions migrate towards the oppositely charged electrodes. Membranes are placed strategically throughout the EDI to facilitate the passage of cations and anions, resulting in a concentration depletion of the feed solution. Conventionally, electrodes are placed at the extremities of an EDI device, then the power source is connected to those to create an electric current through the entirety of the EDI.

In active wafer electrodionization, mesh electrodes are used in inner compartments of the device. This operational feature allows for different possibilities of where the current can be applied, providing versatility to ion removal processes in the sense that wafers with different functions can be easily activated or deactivated. A wafer will be activated when its chamber is within the line where the electrical current is applied. Additionally, using mesh electrodes allied with strategical membrane and wafers positioning are promising factors for manipulating the ion transport and thus controlling the process. Our experiments suggest that this strategy can be applied to enhance monovalent cations removal. An AWEDI with 1 active wafer removed 3x more sodium and potassium than a 1 wafer EDI.