Method and apparatus for making electrolyzed water
An insulating end cap for a cylindrical electrolysis cell the type comprising at least two tubular electrodes with a cylindrical membrane arranged co-axially between them, comprises a first annular section with first and second axial ends, having at its first axial end a circular seating or one end of an outer cylindrical electrode and at its second end a circular aperture, of smaller diameter than the circular seating and co-axial therewith, to accommodate one end of the membrane. A second annular section of the end cap is detachably secured to the first and has a central circular aperture of smaller diameter than the central aperture of the first section and co-axial therewith, to accommodate one end of the inner cylindrical electrode. The two part construction of the end cap facilitates the assembly of the cell, and reduces the likelihood of breakage of the fragile ceramic membrane.
1. A method of making an electrolyzed liquid comprising:
providing an electrolysis cell comprising an outer tubular electrode separated from an inner tubular electrode by a tubular ion permeable membrane arranged coaxially one within the other and a pair of end caps where the space between the inner tubular electrode and the membrane and the space between the membrane and the outer tubular electrode defines anode and cathode compartments where one of the electrodes functions as an anode and the other electrode functions as a cathode;
providing a liquid comprising water or brine to the electrolysis cell and while in the electrolysis cell is contained within the anode and cathode compartments and the end caps; and
applying a current across the electrodes,
wherein each end cap provides a sealing engagement between the end cap and each of the inner tubular electrode, the outer tubular electrode, and the membrane, wherein the end cap has a lateral inlet through an outer wall thereof, said inlet being provided with a fitting for tangential feeding of the liquid to the inside of the end cap, and
wherein the end cap comprises:
a first annular section of insulating material with first and second axial ends, having at its first axial end a circular seating for one end of the outer cylindrical electrode and at its second end a circular aperture, of smaller diameter than the circular seating and coaxial therewith, to accommodate one end of the cylindrical membrane, and
a second annular section of insulating material detachably secured to the first annular section and having a central circular aperture, of smaller diameter than the central aperture of the first annular section and coaxial therewith to accommodate one end of the inner cylindrical electrode.
2. The method of claim 1 , wherein the ion-permeable membrane is a ceramic membrane.
3. The method according to claim 1 , wherein the ion-permeable membrane comprises alumina, zirconia, or a mixture thereof.
4. The method according to claim 1 , wherein the ion-permeable membrane comprises a ceramic a transition metal oxide that is an oxide of a transition metal selected from the group comprising of titanium, niobium, tantalaum, iridium, ruthenium, rhodium, palladium and mixtures thereof.
5. The method according to claim 1 , wherein the anode and cathode, or both, comprise a titanium base activated with a coating structure comprising platinum and at least one other transition metal oxide.
6. The method according to claim 5 , wherein said at least one other transition metal oxide is an oxide of a transition metal selected from the group comprising of titanium, niobium, tantalaum, iridium, ruthenium, rhodium, palladium and mixtures thereof.
7. The method of claim 1 , wherein the liquid is brine and the method further comprises, isolating a biocidal liquid, a sporicidal, or both, having a pH ranging from 2 and 8.5 and a positive redox potential ranging from 600 to 1200 mV.
8. The method of claim 1 , wherein the liquid is brine and the method further comprises, isolating an alkaline biocidal liquid having a negative redox potential ranging from 600 to 1200 mV.
9. The method of claim 1 , wherein a portion of the liquid exiting the cathode chamber is fed into the anode chamber.
10. The method of claim 1 , wherein the liquid is fed successively through the cathode chamber and the anode chamber to produce an neutral anolyte (ANK) solution.
11. The method of claim 1 , wherein the current is at least 20 amps.
12. The method of claim 1 , wherein the current is at least 2.5 amps.
13. The method of claim 1 , wherein the liquid is supplied to both the anode and cathode compartments at a lower part of the electrolysis cell and an anolyte and a catholyte are obtained from an upper part of the cell.
14. The method of claim 1 , wherein a spiral feed of the liquid is fed to the anode and cathode compartments.
15. The method of claim 1 , wherein the current is a rectified square wave direct current is applied across the electrodes.
16. The method of claim 1 , wherein the first annular section comprises an inlet fitting connected to an inlet tube that passes tangentially through the first annular section of the end cap to communicate with the anode chamber through an aperture.
17. The method of claim 16 , wherein the second annular section comprises an inlet fitting connected to an inlet pipe that passes through the second annular section of the end cap to communicate with the cathode chamber through an aperture.
18. The method of claim 1 , wherein the second annular section comprises an inlet fitting connected to an inlet pipe that passes through the second annular section of the end cap to communicate with the cathode chamber through an aperture.