What to do with lye gone bad

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dibbles

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Getting ready to soap this morning I found that my lye bottle had split lengthwise. There were a few drops of what I assume to be dissolved lye. I have no idea as to what caused this, but at any rate I want to dispose of the lye. There is probably 3/4 of a 2 lb bottle. In doing a search for lye disposal, I've read not to mix and pour down the drain if you have a septic system - which I do.

Is there a way to neutralize the lye for safe disposal? I don't mind if I have do it slowly over time, say a cup or two until it's gone. Or mixing a small amount of lye into a large amount of water, letting it sit for a couple of days and then pouring it down the drain?

Any suggestions are greatly appreciated.
 

dixiedragon

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I honestly think you'll be okay to use it. Maybe make a small batch and see if it goes to plan. My lye lasted 10 years in a damp basement in a big plastic jar - I think yours is okay.

But if you still want to dispose of it, I'd get a plastic container (number 2 or 5), and put it in there. Dissolve some in water and run it down your sink, bathtub and toilet to help clean the pipes. We have a septic system also and, honestly, I don't think lye is worse than Draino.
 

dibbles

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Thanks dixiedragon. I will have to look more closely at the lye in the container. It seems like there were some clumpy areas in there. Maybe all isn't lost.
 

DeeAnna

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I have a septic system and I occasionally put some lye down the drain. It's fine as long as you don't do it a lot and if you dilute it well with cold water.

I think Dixiedragon has a good suggestion. If there are any unusually hard or solid clumps or any liquid from the NaOH absorbing water from the air, I'd discard this. But if any of the NaOH is reasonably pourable -- what you would normally expect to see if the container hadn't split -- I'd use that in soap myself.
 

Lee242

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Draino is lye based with a few other things mixed with it.
 

lsg

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I too, pour my lye down the drain, followed by lots of cold water.
 

dibbles

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Thanks for the advice everyone. I don't know why some amount of lye can't go into a septic system. I hadn't heard that until I did a search before posting my question.
 

Steve85569

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Diluted lye followed by a bathtub or less of water - just several gallons. Use your household plumbing as usual for the next several days. Follow up by adding some septic tank bacteria after that.

We just add bugs every three or four weeks for general purposes. Keeps everything digesting properly in the tank and the field.
 

Soapmaker145

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You can use it to neutralize citric acid if you use it in your soaps. Just use a pH paper and take the solution to about 9 or 9.5. Alternatively, buy a big bottle of vinegar and use the NaOH to slowly neutralize it. Save it for your next batch of soap. If you make your own laundry soap, use it to make that.

If you can see evidence that it absorbed a significant amount of water, my suggestion is to run a simple experiment to estimate how much water was absorbed by the lye. Open a new bottle and weigh 20 to 50 g of the lye and let it sit in a safe place exposed to air. It should absorb water from the air. When you think it looks the same as the open bottle, weigh it again to see how much water it absorbed. Once you have that, you can adjust the weight accordingly and just make soap like usual without the doubt or uncertainty.
 

dixiedragon

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Some people think that septic tanks are super delicate. They're not. Our plumber told us that sour milk is like yogurt for septic tanks. So, whenever you have dairy products that go bad, run them down the sink.
 

dibbles

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Some people think that septic tanks are super delicate. They're not.
I think you hit the nail on the head here. Which would explain the warnings re pouring lye down the drain into a septic system. It is a terrible experience when they fail, though...I understand the caution.
 

Steve85569

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Bleach ( chlorine) and all the anti bacterials are much worse on septic systems than lye. Anything that kills bacteria will destroy the system's ability to process material. I'd go in to the different type of bacteria and what they do but suffice it to say there should be a happy family of bugs throughout the system.

Sour milk is full of the aerobic bacteria. There are also bugs that do not like oxygen - the anaerobic family that also do their job.
 

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