Electrochemical reactor and process

A method for producing a chemical product including hydrogen peroxide, the method comprising:

• introducing a liquid anolyte into a first half-cell of an electrochemical reactor, wherein at least one chemical species of said liquid anolyte is oxidized at an anode electrode of the first half-cell;
• introducing a liquid catholyte into a cathode chamber of a second half-cell of the electrochemical reactor, wherein a porous cathode electrode permeable to gas and liquid is disposed in the cathode chamber;
• introducing a feed of a gas into the cathode chamber through an electrically-nonconductive, hydrophobic, gas-permeable gas distributor to mix with said liquid catholyte and create in the cathode chamber a multiphase catholyte solution including a liquid phase and a gas phase with the multiphase catholyte solution in contact with the cathode electrode;
• generating hydrogen peroxide in the cathode chamber, comprising reducing at least one chemical species of said multiphase catholyte solution at said cathode electrode;
• removing a reduced multiphase catholyte product comprising the hydrogen peroxide from said second half-cell and removing an oxidized liquid anolyte product from said first half-cell;
• and
• after performing the generating hydrogen peroxide for a period of time, discontinuing operation of the electrochemical reactor to stop the generating hydrogen peroxide, after the discontinuing performing a catholyte electrode reactivation process and after performing the catholyte electrode reactivation process re-commencing operation of the electrochemical reactor to re-restart the generating hydrogen peroxide, wherein the catholyte electrode reactivation process comprises:
• subjecting the cathode electrode in the cathode chamber to electrochemical reduction;
• and
• flushing the cathode electrode in the cathode chamber with an activation solution comprising peroxyacetic acid;
• and wherein:
• the electrochemical reactor further comprises:
• an ion permeable separator separating the first half-cell and the second half-cell, wherein the ion permeable separator is disposed to one side of the cathode electrode and the gas distributor is disposed to an opposing side of the cathode electrode;
• a housing enclosing the first half-cell, the second half-cell and the ion permeable separator;
• and
• a gas chamber disposed within the housing and located on a side of the gas distributor opposite the cathode chamber and the cathode electrode;
• and
• the generating hydrogen peroxide comprises applying electrical power to the electrochemical reactor to provide electrical current through an electrical current conduction path through the electrochemical reactor, the electrical current conduction path including the anode electrode and the cathode electrode and not including the gas distributor.