what is this? waste treatment.

[nickton]

I didn't really want to start a whole new topic but just couldn't find any place to post these pictures of crystals I got from evaporating my final waste solution, after cementing with aluminum, then adjusting to a neutral ph with sodium bicarbonate and some sodium hydroxide (Briefly). I think it is simply salt:

Well it is obviously some kind of salt.

As far as I can guess, the material left after evaporation would be anything above aluminum in the reactivity series, as well as baking soda and lye powders (???).

The orange/brown color must be iron oxide I think too.

I washed some of the salt crystals in water and have a jar of cleaned material I don't have a picture of yet. But it doesn't dissolve (at least easily) in water.

I have the earlier filtered precipitations in separate jars. Unfortunately since this was my first stock pot I had done a few things out of order, like adding salt, copper, and iron at various stages. I now have a better understanding of what to do.

 

[nickton]

Here are some more pictures:

 

[nickton]

I also saved the dirtier crystals:

 

[FrugalRefiner]

Instead of "salt", I'd probably label that jar as "toxic waste". If it were mine, I'd hate to think that I might die someday, and someone would come along and think, "Oh look, old Dave had some special salt squirreled away. I'll have to try some of that on my next hamburger."

I know, that's a stretch, but it's the same reason not to use food containers like beverage bottles to store toxic liquids.

Dave

 

[nickton]

yes that's probably a good idea. I don't plan to keep it that way too long anyway. I don't think it's too toxic at this point however, since I have cemented out whatever is below aluminum on the reactivity chart.

Some people have said it is mostly iron oxide and salt. I don't think the added basic powders (baking soda, lye, some ammonia) caused any toxic reaction, but please by all means school me about this if I'm wrong.

I had reached to the point where after attaining a neutral ph, I filtered out all solids, but since the water didn't turn clear, I decided there must be more in there. The only way I could think of to remove soluble remains, was evaporation, which gave me the brownish/orange goop and those crystals.

It's a time consuming process, but I'd rather do it than flush down the drain.

I now have a (well covered) five gallon bucket of this gunk. I think it contains mostly base metals and any pm's are in what I filtered out at earlier stages.

You're right about that salt though. I've seen similar looking stuff from the Dead Sea or Tibet I think. I wouldn't want someone to think it's medicinal.

 

[FrugalRefiner]

I agree with everything you said. I just feel an obligation to be the voice of caution for anyone who may read this thread in the future.

Dave

 

[nickton]

I guess no on wants to take a stab at identification.

 

[UncleBenBen]

I guess no on wants to take a stab at identification.

Get the test tubes out and test it. What does it dissolve in. What won't it dissolve in. Sounds like some fun experimenting to me!

 

[nickton]

I guess that will have to be an entirely new field of research for me. I haven't a clue yet.

 

[Geo]

Wrong shape for sodium chloride.

 

[nickton]

aha. I was wondering about that. It did seem a little off to me but I wasn't sure why. I'd like to find a resource for crystal formation shapes perhaps. In fact I think I'll search it now. I notice these can become very long and straight. :mrgreen:

 

[nickton]

Looks a bit more like magnesium sulfate. I think I'll try to re - crystalize some or them to see if I can get them cleaner or larger.

 

[g_axelsson]

Crystal forms are like fingerprints for molecules. If you know the surfaces and the angles between them then you can identify the compound with a high confidence. For anyone interested the science is called crystallography ( https://en.wikipedia.org/wiki/Crystallography ), the science of packing atoms and molecules together into crystals. A stunning example is the nine volumes of Goldschmidt's Atlas of Crystal Forms. A bible for mineralogists.

There are a number of basic crystal forms, triclinic, cubic, hexagonal... if you study the form of the crystal you can put it into one of the major groups. Then list what metals could have ended up in solution in the end and what anions (sulfate, chloride, hydroxide...) is in the mix. The crystals are made from a mix of these.

Personally it looks like gypsum crystals, calcium sulfate, but I don't think it's so easy to make it into nice crystals on a lab scale. It probably needs geological time scale to work. At least years.

You could also test density and solubility easily enough.

Göran

 

[nickton]

thanks for the links. I'll have to check them out.

 

[nickton]

I tried the links and learned a lot, stumbling on "the gold museum", a great site for gold eye candy, containing an excellent section explaining gold crystal formations, and photos of many amazing nuggets. Can't figure out how to share the link but I do recommend it to those who haven't checked it out yet. :G

I'm think I will try to grow larger crystals from my stock pot material.

 

[FrugalRefiner]

See Including Links.

Dave

 

[Geo]

Calcium sulfate makes a really fluffy pearlescent white crystal that looks like powder. I accidentally made some trying calcium nitrate for poor mans AR. So I tested some in a non-metal processing test and it made the same fluffy white pearlescent powder.

Edit : It formed when I added SMB. I was scared and amazed.

 

[nickton]

Here's some more detailed pictures of the crystals, from a new batch of evaporation:

 

[nickton]

This one I thought looked best:

 

[nickton]

I can rinse them off but they are pretty delicate and do seem soluble, dissolving slightly as I rinse them. They remind me a bit of ice. Though it is not freezing where I live, I wondered if this could be a mix of materials with a higher freezing point than water.