Aussiedistiller, Home Distilling, Moonshine, Home Brew

d

MartinCash wrote:A note and a question:

I get blackening of my structured copper packing after refluxing rum feints washes, and it looks vaguely like your pictures. Citric acid wash helps.

Q: Why do you use structured copper in your pot still? Is it all stainless? If so you might find that copper scrubbers in your boiler (in the wash) help equally well and also act to smooth out the boil (at least in my gas-fired setup).

Hi Martin, sorry I realised I forgot to mention, yes I use some copper in the boiler, but only when I'm doing my spirit runs. It's good advice, every bit of sulphur you can get out is a good thing. Can't remember why I don't use it in my wash runs, I will have to look at my notes. It was probably just a cleaning thing.

BPR2011 wrote:Hey Sam, the copper shown in my photos is probably not so pure (but not in the way of coating, just in the way of other things being smelted in the same pot/contamination in manufacturing), as it was just some backup copper that I ordered from eBay to try out, but the chore boys are reported to be pretty pure pure (minus a tiny bit of a mineral oil coating from the manufacturing process), and pretty much it's the same reaction.

Hey Maxx, very nicely chromed copper. I'm curious, what is your normal cleaning procedure? The a multiple wash procedure, or do you do something different?

Hey BPR2011
I have a whole bucket of those little copper bits with holes, normally I just use fresh ones but when they all get dirty I dump the lot in a half full 50 litre tub of Luke warm water and a cup of 100% sodium percarbonate and rinse twice after about 3-4 hr soak. They come up like new.
Cheers
Maxxx

Ha that is genius. Of course. Sodium percarbonate is just a bit of extra O2, and 4Cr + 3O2 -> 2Cr2O3 (back to Cr2O3, the oxide coating normally on stainless).

So basically, the chromium just oxidises, forms back into its' oxide coating, and falls away or continues on reacting to form other compounds.

Do you do an acid bath afterwards to clean the copper up? Do you end up with a lot of oxides?
I have many questions, but I will do some tests over the weekend to save bombarding you with them.

I will do some copper cleanup experimenting and post some results. I realised I can't find any of my rare earth magnets (I have no idea how the heck I always lose these, my guess is there is a moving truck out there somewhere just filled with small rare earth magnets), so I'll need to wait for some new ones to arrive to have a go at that. (I have an idea).

I've got plenty of citric acid, so I will do a full pickle and passivation on my stainless reaction pipe, do a low wines run, and see how I go having fun with the cleanup a few different ways.

My gut is telling me: ultrasonic cleaner, citric acid bath, and a rare earth magnet teabag.

Also, re the extra O2, I mean H2O2, as in Sodium Percarbonate (Na2H3CO6) degrading in water to form Sodium Carbonate (Na2CO3, the alkaline) and Hydrogen Peroxide (H2O2, the oxygen).

Feel free to start a new thread with your cleanup experiments, watching with interest :-B

BPR2011 wrote:Also, re the extra O2, I mean H2O2, as in Sodium Percarbonate (Na2H3CO6) degrading in water to form Sodium Carbonate (Na2CO3, the alkaline) and Hydrogen Peroxide (H2O2, the oxygen).

Hey BPR 2011
Your chemistry is way better than mine,
It does clean the copper well (and stainless) it gives off plenty of oxygen in the process.
I normally just rinse well no acid required.
You have peaked my interest witH the neo magnets though- how were you thinking of using them
Cheers
Max

Maxxx wrote:Hey BPR 2011
Your chemistry is way better than mine,
It does clean the copper well (and stainless) it gives off plenty of oxygen in the process.
I normally just rinse well no acid required.
You have peaked my interest witH the neo magnets though- how were you thinking of using them
Cheers
Max

Hey Max,.

Chromium itself is antiferromagnetic below 38C (paramagnetic above that, no good), so it will actually somewhat become part of a strong magnetic field (weakly though), so a cooled chromium containing solution with a very strong magnet teabag should gather some chromium on its' own.

There is a process to make Chromium magnetic though:
First you need CrO3 (see below), then you need to run the reaction to 526.85C at 2000 bar pressure in water (so easy right?) 3CrO3 + Cr2O3 -> 5CrO2 + O2

CrO3 can be formed by 2Cr + 3O2 -> 2CrO3

Tongue is in cheek :D

I'm going to try and soak just it out in a weak acid (citric, low concentration acetic), and put a few teabags of really strong bag of rare earth magnets near the surface to see what I get whilst it cools to our winter over night temperatures.

There is also the "eat the metal method" though.

2Cr (Chromium Metal) + 6HCl (Hydrochloric Acid) -> 2CrCl3 (Chromium(III) chloride) + 3H2 (Hydrogen) [Redox reaction, Single displacement (substitution) reaction]

Chromium(III) chloride is water soluble, but Captain Planet will turn you into a tree if you flush it down the drain.

So Chromium teabag with super strong magnets first, then there's always HCl for the cleanup, but take out the copper or you will produce Cu + 2HCl = CuCl2 (Copper(II) chloride, water soluble) + H2.

Then, treating the CrCl3 with a few options. Bad ones and good ones (try and avoid equalibrium reactions). 2CrCl3 + H2O2 -> 2CrCl2 + 2HCl + O2

But again, I'm trying to teabag method as soon as my magnets arrive first.

Also everyone, tried new copper today from 5 Star, very minimal chrome. Different wash recipe though and stuck it in right at the last second so we'll see after the next time I run the same low wines recipe as before. Got to say of the 5 Star copper mesh, it is probably the most pure copper I have seen so far.