Anodizing titanium with trisodium phosphate (TSP)

A. Hi Scott. Although I don't know exactly how to account for the time difference in your two scenarios, I remain confident that Faraday's Law holds in this case and all cases.

Luck & Regards,

A. If I were you, I'd still be most concerned about your home-built 180 VDC power supply, as that is way more than adequate to kill you if you didn't design and construct it properly.

1. trisodium phosphate ⇦this on eBay or Amazon [affil links] is a pretty mild chemical; I can't foresee any violent reaction with copper, silver, aluminum, or titanium.

2. What is the gas? Probably hydrogen. Depending on pH and other conditions, water separates into 2 parts hydrogen and 1 part oxygen, or 1 part hydrogen and one part OH-

3. Again, trisodium phosphate is a pretty mild chemical, not much different than cola. But there is probably metal dissolved in the solution, so it's somewhat poisonous. Is it safe to leave an open container out? Well, is it safe to leave an open bottle of aspirin out in the open? Yes if you're the only one around; no if there's a toddler about.

4. Ionized copper is normally blue rather than green, still the color is probably coming from the copper. No, you certainly weren't plating copper onto an anode! You were probably oxidizing the brass, and perhaps surface enriching it by leaching out some of the zinc.

As you probably know, you ask for reassurance that what you are doing is safe, and pose questions where we can't foresee a direct danger. Which leaves us sort of implying: "yeah, that's safe . . . yep, that's safe too . . . uh-huh, no problem with #3 either . . . you're okay with #4, too.

So now you've heard this 4-part mantra of how we see nothing dangerous in what you are doing, and you are probably reassured that you can experiment to your heart's content, although you've acquired no appreciation of the chemistry. So you are right on track to tossing a cup of table salt into your bucket and killing yourself with chlorine gas, or knocking a beaker of solution onto your power supply and lunging for it just as the highly conductive solution runs down into the AC side, or who knows what :-(
Chemistry and electrochemistry can be dangerous.

A. If you used an isolation transformer in the unit , you are fairly safe. Not everyone can stand the same amount of electricity. 180 V is obviously a lot more dangerous than 6 volts and deserves due caution. Amperage is the other part of electricity killing people. Fuse it or circuit breaker the output side with "quick blow" units and fuse to the minimum amount that you can get by with. TSP is still sold for cleaning before wall papering and was the main ingredient of some detergents until it was found to grow great amounts of algae. I would keep the other metals out of the tank. They are dissolving and you are really into some nasty waste disposal problems. Titanium is non regulated and very very little dissolves when used as a cathode. (or anode) Normally a very well organized and neat line with normal lab practices is safe. Rubber rubber gloves ⇦this on eBay or Amazon [affil links] and safety glasses. Nothing can save you from stupid mistakes, so follow good practices and enjoy the product.

Yeah, I only anodize titanium using the 'normal' process I learned under supervision years ago. I've seen it repeated over & over again from different sources also, so figured it was safe enough. But I wouldn't recommend that anyone build any power supply unless they have enough experience with them. It's like a hair dryer in the bathtub the whole time when you anodize, and you must treat it as such. Dry, heavy rubber gloves are absolutely mandatory at all times! I also would never have the power supply on while manipulating items. Makes *nice* colors though, I've made chains from one type of titanium and simple rings from another. Beautiful metal with lots of possibilities! Makes it worth the trouble.