Make your own NAOH?

[rickbb]

With the possibility that local sources of NAOH may stop selling it I went searching online for source. Looks like Dudadeisel has the best deal.

But ran across some guy on YouTube that says you can make your own. He uses non iodized salt in distilled water and electrolyzes it with carbon anodes and a piece of zinc in the bottom of the container. He says the zinc is just to covert any sodium hypochlorite back to a chloride to be electrolyzed into hydroxides.

Of course being on YouTube he doesn't give any more details than that, so I'm asking here. Is it really that simple? Just run salt water in a cell with a hunk of zinc and you make NAOH.

 

[butcher]

I cannot see NaOH sodium hydroxide (caustic soda), or potassium hydroxide KOH, not being available as it has been used for thousand of years, and has always been a useful and needed in many applications.

Hardwood ash from your fireplace, leached with rainwater, is a good source of potassium hydroxide (Lye).

Just make it like your grandparents did.

I am surprised if you have not seen this made and used, I grew up in the area close to where you are, and remember making it as a kid, and have made it for various reasons ever since, it is great for removing hair off an animal hide before tanning the leather, soap is cheap nowadays.

 

[etack]

Ace Hardware will get it for you.

Eric

 

[solar_plasma]

http://goldrefiningforum.com/~goldr...p?f=53&t=1022&p=207979&hilit=lime+ash#p207979

 

[rickbb]

I don't know why I'm so incompetent with the search function, (and I do computers for a living), after going to your link I even remember reading that post. (Face in palm moment. )

For some unknown reason the police industry has convinced itself that if they bully retailers into removing it from the shelves it will somehow make a dent in local meth production. It won't, addicts will always find a way, they always have and always will.

We no longer have an Ace Hardware, the big box boys have run them all out of town in these parts. It's getting close to order online or make your own time.

I have seen and helped my grandmother make lye from wood ash and soap too when I was a kid. But my memory of it was that it's not pleasant or easy.

Is there an easy way to determine the strength of home made NAOH? For instance if I need a 20% solution.

 

[necromancer]

here is a link for walmart (usa) here in canada they will ship to your door for free or ship to your closest store
http://www.walmart.com/search/?query=lye

there are walmarts everywhere. they have also killed all the mom & pop shops here too.

 

[butcher]

You can do the test with an egg (to see if it floats).
https://www.google.com/?gws_rd=ssl#q=potassium+hydroxide+from+wood+ash+floating+egg

Or use an acid titration method.

 

[rickbb]

My grandmother used the feather method, (she wouldn't waste an egg on it), but that and the egg are yes/no tests that tell you it's good enough for soap.

I guess a hydrometer is next on my wish list to acquire if I'm going to embark on a make your own path. (Boy my wife is going to love that.)

Interesting home made hydrometer from one of those links.

"To test the strength of the lye you need a saturated solution of salt. Dissolve chemical-free salt in a pint of water until no more salt will dissolve. Take a stick and put a small weight on the end of it and float it in a pint of the salty water. The weight will sink to the bottom, while the top of the stick will float. Make a mark on the stick where it reaches the water line. Then float the stick and weight in a pint of lye. The mark on the stick will probably be above the water mark of the lye. If so, stir in some more rainwater until the mark on the stick is in exactly the same place it was in the salt water. You now have the correct distillation of lye for making soap."

 

[rickbb]

I don't know why I'm so interested in this, I can get it from Dudadiesel easy enough even with shipping it's virtually the same price as the local big boxes.

But I have found that salt water cells can and do make pure NAOH. Below is a description of a membrane cell from http://www.ausetute.com.au/chloralkali.html

Another site I looked at said you can make a membrane for this type of cell out of regular cement. You pour it into a form to make a sheet 1/8 to 1/4 inch thick for the separator membrane. I'll never build one, but still interesting.


"•Membrane Cell

Favored method for producing sodium hydroxide as there is no hazardous waste, very pure sodium hydroxide is produced and it has the lowest energy requirements.

Ion-exchange membrane selectively allows Na+ and water to flow to the cathode compartment but prevents products from moving between compartments.

Saturated brine enters the anode compartment where chlorine gas is formed.

Anode (positive electrode):
titanium

Anode reaction (oxidation):
2Cl-(aq) -----> Cl2(g) + 2e

Cathode (negative electrode):
nickel

Cathode reaction (reduction):
2H2O(l) + 2e -----> H2(g) + 2OH-(aq)

Na+ migrates across the membrane to cathode compartment combining with OH- to form NaOH.

Overall cell reaction (showing Na+ spectator ions):
2H2O(l) + 2Cl-(aq) + 2Na+(aq) -----> 2Na+(aq) + 2OH-(aq) + H2(g) + Cl2(g)

Product is concentrated sodium hydroxide. "

 

[solar_plasma]

Too much mess with electrolytic cell for my taste. I would just use about stoichiometric amounts of Na2CO3 and Ca(OH)2, stir for a day, settle for two other, filter, test a probe with acid for CO2 and if no CO2 evolves, filter and store.

Na2CO3(aq)+Ca(OH)2(s)=>NaOH(aq)+CaCO3(s)

Using one mol (106g) NaCO3 (washing soda) in one liter solution makes 1 liter 1M NaOH.

Equally with K2CO3, that can be extracted and crystalized from ash.

 

[Beirdo]

I seem to remember reading that if you want homemade NaOH (as opposed to KOH from wood ash), you can burn seaweed or driftwood from the ocean, and use the ashes from that the same way you would use the wood ash to leach out the caustic lye. I have not verified this though.

Either way, even if it's not commercially available, we will always have lye in some form available unless the burning of wood and the like is completely outlawed, and good luck affecting that law.

 

[goldsilverpro]

Making NaOH is a fool's errand unless you are a survivalist type. Making it costs more than buying it. Your labor counts.

 

[meatheadmerlin]

From the survivalist perspective, I was curious if one could make lye from cigarette ash.
It seemed quite possible, I happen to have a regular supply of it, and
for someone on a fixed income the actual cash expenditure vs the cost of my time
is probably different than for most.

So, I extracted a solution from the ash as one would from wood ash.
Evaporating the solution produced fine white crystals.
Now, I don't yet have pH testing equipment, so I improvised.

I took 2 glasses and put a 1/4 cup of white vinegar in each.
I mixed up a moderately concentrated solution of my crystals to test.
I put a tablespoon of this solution in one glass, and a tablespoon of plain water in the other.
It might be worth noting that adding the test solution to the vinegar produced a few large-ish bubbles.
Then, I added a 1/4 teaspoon of baking soda to each glass.
The vinegar with plain water fizzed as expected.
The vinegar with the test solution did not fizz at all.
From this I concluded that the test solution was in fact basic,
and guess that it is probably mostly potassium hydroxide.

 

[NoIdea]

Evening All - just a few quick comments, firstly I believe that wood ash comprises of mainly carbonates not the hydroxide, the carbonates, in high enough concentrations, will produce a high pH, around 14. Both sodium and potassium hydroxide react very quickly with atmospheric carbon dioxide.

Secondly there is a method of using sodium sulphate and calcium hydroxide (lime) resulting in sodium hydroxide and calcium sulphate.

Regards

Deano

 

[kurtak]

Hardwood ash from your fireplace, leached with rainwater, is a good source of potassium hydroxide (Lye).

it is great for removing hair off an animal hide before tanning the leather,

Interesting you bring that up butcher - Years ago (when I was in high school) I played around with making leather (from my deer hides) & that is exactly how I de-haired them

Also - after I moved back home to Wisconsin (which was about 6 months after I first started playing around with refining & about the time I first joined the forum) I had my brother save all his ash from his wood fired boiler (house heating) I would soak the ash in water & then use it for treating my chem waste from refining

worked great - but a couple years ago he replaced the wood fired boiler with a propane fired boiler - so I lost my "free" source of waste treatment chem

He burned nothing but oak & maple so it was a good hardwood ash & it (the boiler) was very efficient in it burning so very little (if any) carbon/charcoal in the ash

Kurt

 

[kurtak]

Evening All - just a few quick comments, firstly I believe that wood ash comprises of mainly carbonates not the hydroxide, the carbonates, in high enough concentrations, will produce a high pH, around 14. Both sodium and potassium hydroxide react very quickly with atmospheric carbon dioxide.

Regards

Deano

Yes (per the above underlined) from Wiki --- Much wood ash contains calcium carbonate as its major component, representing 25 or even 45 percent

And then also from Wiki --- Historically KOH was made by adding potassium carbonate (potash) to a strong solution of calcium hydroxide (slaked lime), leading to a metathesis reaction which caused calcium carbonate to precipitate, leaving potassium hydroxide in solution:

Ca(OH)2 + K2CO3 → CaCO3 + 2 KOH

Filtering off the precipitated calcium carbonate and boiling down the solution gives potassium hydroxide ("calcinated or caustic potash"). It was the most important method of producing potassium hydroxide until the late 19th century, when it was largely replaced by the current method of electrolysis of potassium chloride solutions

Kurt

 

[Rougemillenial]

if you can, I'd purchase some mercury from a prospecting shop put an inch of it into a container and top it off with salt water as this eliminates the hypochlorite side reaction and the need for a divided cell. Put a carbon electrode in the water as the cathode and a thick copper wire wrapped with standard electrical tape all the way to 1/2" on both sides to provide electrical contact from the power supply to the mercury while avoiding side reactions. then power it up. this makes sodium metal dissolved in mercury along with hydrogen, oxygen and chlorine. then when you're satisfied with the concentration, you can remove the electrodes and pour off the salt water quickly washing a couple of times with fresh water to remove salt. then let it sit with an equal volume of water so the sodium reacts releasing hydrogen and making very pure lye. this migrates to the water layer thus freeing up the mercury to be used in future runs. This was a Cody's lab prep I found on YouTube titled making lye from salt. 8)

 

[g_axelsson]

Cody's lab isn't the most safety conscious channel I have seen... rather at the other end of the scale. He has a total lack of how toxic mercury can be.

I would avoid mercury as long as I can, lye isn't that hard to get after all. If anything else fails just check ebay or amazon.
Mercury forms invisible fumes that can affect your body in the long term.

Göran

 

[goldsilverpro]

More worthless information from rougemillenial.

We don't discuss the use of mercury on this forum. It's not needed for anything we do.

I Know Cody is a member and he seems to be a good guy but I haven't seen one of Cody's videos that I thought was any good. Too sloppy and dangerous and much worthless information.

 

[Rougemillenial]

More worthless information from rougemillenial.

We don't discuss the use of mercury on this forum. It's not needed for anything we do.

I Know Cody is a member and he seems to be a good guy but I haven't seen one of Cody's videos that I thought was any good. Too sloppy and dangerous and much worthless information.

I apologize for the irrelevance, I thought it could be another way of doing it that wasn't mentioned. I admit that lye can just as easily be made by decomposing sodium carbonate at high temperatures to form sodium oxide or simply using a divided cell instead of putting zinc in the bottom of the cell as creativepyroscience did in a youtube video from a couple years ago, though if you need high amounts or high purity for your work, I suggest buying it online as It's much easier and safer than making it yourself.