Abstract: An acidic treatment liquid processing apparatus includes: a tank having an interior space; a diaphragm permeable to a metal cation and separating the interior space of the tank into a first chamber and a second chamber; a first electrode disposed in the first chamber; a second electrode disposed in the second chamber; a power supply configured to apply a voltage while using the first electrode as an anode and the second electrode as a cathode; a first liquid passing part configured to pass an acidic treatment liquid containing a dichromate ion and a metal cation into the first chamber; and a second liquid passing part configured to pass an acid aqueous solution into the second chamber.

Abstract: In an acidic treatment liquid processing apparatus, a space between a first electrode and a second electrode spaced from each other is separated by a first diaphragm permeable and a second diaphragm into a first chamber, a second chamber, and a third chamber. While the first chamber is fed with an acidic treatment liquid containing a dichromate ion and a metal cation, the second chamber is fed with a first acid aqueous solution, and the third chamber is fed with a second acid aqueous solution, a voltage is applied using the first electrode as an anode and the second electrode as a cathode.

Abstract: A process for treating an electrolytic solution to recover a concentrated solution from a dilute one in an electrolytic cell or in each of such cells divided by a permeable diaphragm into a feed chamber and a recovery chamber provided, respectively, with positive and negative electrodes or vice versa. A dilute electrolytic solution is fed to the feed chamber, and, while electrolysis is in progress between the electrode of the feed chamber and the electrode held in the recovery chamber in close proximity to, or in intimate contact with, the diaphragm, the electrolyzed solution is allowed to exude through the diaphragm into the recovery chamber, whereby the concentrated solution is extracted into the latter chamber. In the apparatus for practicing the process, either the negative or positive electrode is held in the feed chamber and the other electrode is held in the recovery chamber in close proximity to, or in intimate contact with, the diaphragm.

Abstract: A process for treating an electrolytic solution to recover a concentrated solution from a dilute one in an electrolytic cell or in each of such cells divided by a permeable diaphragm into a feed chamber and a recovery chamber provided, respectively, with positive and negative electrodes or vice versa. A dilute electrolytic solution is fed to the feed chamber, and, while electrolysis is in progress between the electrode of the feed chamber and the electrode held in the recovery chamber in close proximity to, or in intimate contact with, the diaphragm, the electrolyzed solution is allowed to exude through the diaphragm into the recovery chamber, whereby the concentrated solution is extracted into the latter chamber. In the apparatus for practicing the process, either the negative or positive electrode is held in the feed chamber and the other electrode is held in the recovery chamber in close proximity to, or in intimate contact with, the diaphragm.