Sciencemadness Discussion Board - Anyone needing MMO? - Powered by XMB 1.9.11 (Debug Mode)

Anyone needing MMO?

hyfalcon - 16-10-2014 at 06:34

Lasered is at it again if anyone needs MMO.

http://www.ebay.com/itm/MMO-coated-expanded-titanium-mesh-an...

j_sum1 - 16-10-2014 at 07:52

Got me one!
Thanks.

violet sin - 16-10-2014 at 18:13

if you contact him directly from the email provided in the auction listing, you ( and him) can get a better price. I got 2 @ 6.75" X 10" for 60$ + s&h, just fyi :) total paid, 66$ for both :D
-Violet Sin-
this auction: http://www.ebay.com/itm/MMO-coated-expanded-titanium-mesh-an...

here is the email: jmcdonald1967@Gmail.com

nice guy easy to deal with, didn't always get right back to me, but didn't take long at all. fast shipping too

[Edited on 17-10-2014 by violet sin]

BobD1001 - 16-10-2014 at 19:12

Wow he really upped his prices! About 6 months ago I bought two 6 3/4" X 10" sheets for $15 a piece. He must have realized how valuable an item he was practically giving away for $15. Still a very reasonable price for quality MMO anodes though.

violet sin - 16-10-2014 at 20:13

it is still considerably less than most sellers were last time I was in the mood to buy one. I had the habit of checking in on the ebay prices for Pt and MMO anodes periodically, to see how much longer I would have to wait before they were in my price range. think they were in the area of 50$ US for something in the few sq inches (ball park), then it was 20$ for a small strip (1" x4"), then to 30$ for a decent size electrode, now 10$ for something QUITE reasonable in size. I am pleased to still have an interest in the subject as the prices have come down( and my wages went up)

I think his are along the lines of a sweet find from an auction, and were sold simply as Ti mesh. Only to be realized as more valuable later. he had no way of providing any info on the details of the coating, the manufacturer or had any kind of spec sheet. We had talked via email about that, but it wasn't STATED this was the case, just a hunch from our conversation( and *complete lack of info).

I see that they are being used industrially to protect buildings from salt water, so this in my opinion, seems to be one reason they are more affordable. at least one more industry incentive to produce more at a better price.

if they were 15$ each I still would have spent 60$

j_sum1 - 24-10-2014 at 00:47

Arrived today. Thanks. That could well be the fastest delivery from the US ever.
Looks like I am cranking up the H2SO4 production soon.

IrC - 24-10-2014 at 16:25

Quote: Originally posted by j_sum1

Arrived today. Thanks. That could well be the fastest delivery from the US ever.
Looks like I am cranking up the H2SO4 production soon.

Can you explain the method you will use with your MMO anode? Is it electrolysis of CuSO4? I looked at the Instructables page of NurdRage and mention was made MMO would not last long, and I have no Pt coated Ti. While a reasonable sized piece of Platinum coated mesh is beyond my budget for this, I do have some MMO anodes. I have some Carbon electrodes but that has it's own problems. Making H2SO4 is far more useful to me than Chlorates but I do not want to ruin my MMO.

http://www.instructables.com/id/Make-Sulfuric-Acid-by-Copper...

j_sum1 - 24-10-2014 at 18:23

I had not heard of any problems with MMO to make H2SO4. I guess I will find out. It seems to be standing up to the task at the moment. But I have limited current to 2 amps.
Seems to be much better than the graphitie I was using. And my first attempt at a graphite substrate lead dioxide anode really didn't look good at all.

IrC - 25-10-2014 at 07:59

It was in one or two comments. I have a lot of Titanium and Tungsten Carbide. Would either work for H2SO4 from CuSO4? Thinking about building a cell but want to get the best ideas first, especially any concerning materials I have already. Better still if they are ideas that avoid filtering Carbon particles.

j_sum1 - 26-10-2014 at 01:32

First batch of H2SO4 done. Not the slightest dent in my anode.

Off topic but that last bit of Cu2+ is a dog to reduce. I kept cranking up the voltage to get anthing like a reasonable current. And I was producing a lot more H2 than Cu at the end. I thought I understood the process pretty well but there is obviously something I have missed. My acid has a faint blue cast indicating that I haven't quite got it all. But it will be pure enough for my purposes.

Back on topic. The MMO works great. I am not going back to dry cell electrodes.

j_sum1 - 30-10-2014 at 02:36

Quote: Originally posted by IrC

Quote: Originally posted by j_sum1

Arrived today. Thanks. That could well be the fastest delivery from the US ever.
Looks like I am cranking up the H2SO4 production soon.

Well IrC. Looks like you were right. The MMO anode is now no longer functioning properly. I guess MMO is not compatible with production of sulfuric acid via electrolysis. I did not know that. I have seen references to MMO being suitable for sulfuric acid environments but my experience is dfferent. (Case in point) I have viewed the annotations to the Nurdrage video again and did not note any reference to mixed metal oxide anodes.

My latest batch of sulfuric acid looks really interesting. By the end of electrolysis it needed 25V to sustain any current so I knew that something was up. A cursory look at the anode didn't reveal any obvious damage but I guess that most of the coating had disappeared into the solution.
I boiled the acid down to approximately 30% H2SO4. It has a distinct apple green appearance. It also has a white feathery kind of precipitate and small dark smudges of something that looks like it might be metallic. I discarded most of this material when I decanted the acid -- without really thinking. I wish I hadn't been in such a hurry to clean up. Still, some of it made its way into my storage bottle.

So, now I am wondering exactly what I have. I am guessing that there are some Ru and Ir salts. As well as whatever impurities were in my copper sulfate and other stuff picked up on the way. (This batch was me cleaning up some failed previous attempts -- including one attempt at a Ni anode so there is at least some nickel there.)
I doubt that it is worth investigating. I don't really have the analytical skills or equipment to do any testing -- unless someone suggests something obvious and simple. But I am curious. And as far as failings go, it wasn't an expensive one. $10 for the anode was worth the learning experience.

So it looks like I am back to dismantling lantern batteries, extracting the rods and filtering the product if I want sulfuric acid. At least until I perfect my technique for making lead dioxide electrodes. It just is not possible to get OTC H2SO4 around here. Or I could try bubbling some SO2 through H2O2. Only it is not possible to get high concentration peroxide either (or cheap low concentration.)

Back to the electrode and back on topic. Any suggestions on how I might clean the rest of the oxide coating off the MMO electrode? It still looks a dark brown/grey. I may as well have a nice piece of shiny titanium mesh for my element collection if I can get it.

hyfalcon - 30-10-2014 at 03:50

Mechanical buffing with a wire wheel should clean most of the coating off of it, or media blasting. That's how it was prepped for the coating in the first place more than likely. Either that or a chemical etch, but with noble metals you're better off with mechanical removal.

j_sum1 - 30-10-2014 at 04:27

Sand blasting??
I don't really relish the task of cleaning mesh with a wire brush.