External counter electrode

1. An external counter electrode comprising:

a container having a fluid inlet and a fluid outlet, the container being adapted to pass a substantially non-neutral pH electrolyte therethrough between the fluid inlet and the fluid outlet; and

counter electrode material housed within the container and in fluid communication with the fluid inlet and the fluid outlet such that said electrolyte may contact the counter electrode material as it passes through the container, the counter electrode material being selected to have an E° greater than a natural E° of a metal member which is to be in fluid communication with the electrolyte; and

a dc connection to the counter electrode material and adapted to be electrically coupled to said metal member.

2. The external counter electrode of claim 1 , the counter electrode material being selected from the group consisting of: graphite, nickel-base alloys, cobalt-base alloys, nickel-chromium-molybdenum alloys, platinum, platinized titanium, niobium expanded mesh coated with platinum, ruthenium, osmium, rhodium, and palladium.

3. The external counter electrode of claim 1 , the counter electrode material including graphite.

4. The external counter electrode of claim 1 , the counter electrode material including platinum.

5. The external counter electrode of claim 1 , the counter electrode material including platinized titanium.

6. The external counter electrode of claim 1 , the counter electrode material including niobium expanded mesh coated with platinum.

7. The external counter electrode of claim 1 , the container being plastic.

8. The external counter electrode of claim 1 further comprising a pump operatively associated with the container.

9. A system for cleaning a passageway of a metal member comprising:

a metal member having a passageway and a deposit on a surface of the passageway, the metal member having a first natural E°;

a separate container having a fluid inlet and a fluid outlet;

counter electrode material in the container, the counter electrode material having a second natural E° greater than the first natural E°;

a dc electrical connection between the counter electrode material and the metal member;

an electrolyte having a substantially non-neutral pH; and

a fluidic coupling from the fluid outlet to the passageway,

wherein the electrolyte is adapted to flow into the container through the fluid inlet, contact the counter electrode material, flow out the fluid outlet, and into the passageway to thereby clean the deposit from the surface of the passageway.

10. The system of claim 9 , the counter electrode material being selected from the group consisting of: graphite, nickel-base alloys, cobalt-base alloys, nickel-chromium-molybdenum alloys, platinum, platinized titanium, niobium expanded mesh coated with platinum, ruthenium, osmium, rhodium, and palladium.

11. The system of claim 9 , the counter electrode material including graphite.

12. The system of claim 9 , the counter electrode material including platinum.

13. The system of claim 9 , the counter electrode material including platinized titanium.

14. The system of claim 9 , the counter electrode material including niobium expanded mesh coated with platinum.

15. The system of claim 9 , the container being plastic.

16. The system of claim 9 further comprising a pump operatively associated with the container.

17. A method of cleaning a hollow interior of a metal member comprising:

dc coupling the metal member to counter electrode material, the counter electrode material being in a container separate from the metal member and having a natural E° greater than a natural E° of the metal member;

passing an electrolyte having a substantially non-neutral pH through the container so as to contact the counter electrode therein; and

passing the electrolyte from the container into the hollow interior of the metal member.

18. The method of claim 17 further comprising placing the counter electrode material in a plastic container.

19. The method of claim 17 further comprising selecting the counter electrode material from the group consisting of: graphite, nickel-base alloys, cobalt-base alloys, nickel-chromium-molybdenum alloys, platinum, platinized titanium, niobium expanded mesh coated with platinum, ruthenium, osmium, rhodium, and palladium.

20. The method of claim 17 further comprising selecting the counter electrode material to include graphite.

21. The method of claim 17 further comprising selecting the counter electrode material to include platinum.

22. The method of claim 17 further comprising selecting the counter electrode material to include platinized titanium.

23. The method of claim 17 further comprising selecting the counter electrode material to include niobium expanded mesh coated with platinum.

24. A method of cleaning a hollow interior of a metal member comprising:

providing a container housing counter electrode material having a natural E° greater than a natural E° of the metal member, the container having a fluid outlet;

dc coupling the metal member to the counter electrode material; and

fluidicly coupling an electrolyte having a substantially non-neutral pH from within the container to the hollow interior of the metal member via the fluid outlet of the container.

25. The method of claim 24 wherein the container also has a fluid inlet, the method comprising fluidicly coupling the electrolyte from the hollow interior of the metal member to the container.

26. The method of claim 25 further comprising pumping the electrolyte.

27. The method of claim 24 further comprising providing a plastic container for the counter electrode material.

28. The method of claim 24 further comprising selecting the counter electrode material from the group consisting of: graphite, nickel-base alloys, cobalt-base alloys, nickel-chromium-molybdenum alloys, platinum, platinized titanium, niobium expanded mesh coated with platinum, ruthenium, osmium, rhodium, and palladium.

29. The method of claim 24 further comprising selecting the counter electrode material to include graphite.

30. The method of claim 24 further comprising selecting the counter electrode material to include platinum.

31. The method of claim 24 further comprising selecting the counter electrode material to include platinized titanium.

32. The method of claim 24 further comprising selecting the counter electrode material to include niobium expanded mesh coated with platinum.

33. A method of cleaning a passageway of a metal member comprising:

dc coupling the metal member to counter electrode material, the counter electrode material being in a container separate from the metal member and having a natural E° greater than a natural E° of the metal member;

passing an electrolyte having a substantially non-neutral pH through the container so as to contact the counter electrode material therein; and

passing the electrolyte from the container into the passageway of the metal member.

34. The method of claim 33 further comprising placing the counter electrode material in a plastic container.

35. The method of claim 33 further comprising selecting the counter electrode material from the group consisting of: graphite, nickel-base alloys, cobalt-base alloys, nickel-chromium-molybdenum alloys, platinum, platinized titanium, niobium expanded mesh coated with platinum, ruthenium, osmium, rhodium, and palladium.

36. The method of claim 33 further comprising selecting the counter electrode material to include graphite.

37. The method of claim 33 further comprising selecting the counter electrode material to include platinum.

38. The method of claim 33 further comprising selecting the counter electrode material to include platinized titanium.

39. The method of claim 33 further comprising selecting the counter electrode material to include niobium expanded mesh coated with platinum.

40. A method of cleaning a passageway of a metal member comprising:

providing a container housing counter electrode material having a natural E° greater than a natural E° of the metal member, the container having a fluid outlet;

dc coupling the metal member to the counter electrode material in the container; and

fluidicly coupling an electrolyte having a substantially non-neutral pH from within the container to the passageway of the metal member via the fluid outlet of the container.

41. The method of claim 40 wherein the container also has a fluid inlet, the method comprising fluidicly coupling the electrolyte from the hollow interior of the metal member to the container.

42. The method of claim 41 further comprising pumping the electrolyte.

43. The method of claim 40 further comprising providing a plastic container for the counter electrode material.

44. The method of claim 40 further comprising selecting the counter electrode material from the group consisting of: graphite, nickel-base alloys, cobalt-base alloys, nickel-chromium-molybdenum alloys, platinum, platinized titanium, niobium expanded mesh coated with platinum, ruthenium, osmium, rhodium, and palladium.

45. The method of claim 40 further comprising selecting the counter electrode material to include graphite.

46. The method of claim 40 further comprising selecting the counter electrode material to include platinum.

47. The method of claim 40 further comprising selecting the counter electrode material to include platinized titanium.

48. The method of claim 40 further comprising selecting the counter electrode material to include niobium expanded mesh coated with platinum.