Trying to make greywater safe liquid soap

[user 18839]

Hi All,
While I've made soap before, I've not ventured into liquid soap. I've read up and am willing to try the process but need a little help with the formula.

We have our laundry hooked up to a greywater system (drought here in CA). I've been using small amounts of grated diluted coconut oil hard soap, but seems the sodium in the sodium hydroxide is not so good for plants. Potassium hydroxide, when saponified, won't be a problem. Plants can actually use the potassium, at least in the small amounts that will come through the laundry.

Then I hit a snafu - borax/boron are also no good for the plants.

So I'm trying to figure out proportions to make a coconut oil liquid soap that I either don't have to "neutralize" or use a small amount of citric acid.
The basic Summer Bee Meadow calculator says for 16 oz of coconut oil to use 4.3 oz of KOH and 12.89 oz of water in the first part. On the advanced calculator, it says to add 5 tbsp of Borax diluted in the neutralization phase.

Thoughts on converting this to citric acid or otherwise lowering the KOH to avoid an excessively alkaline soap? I'm not concerned if the soap isn't clear. I just want it to not leave a film (hence the coconut - other oil suggestions welcome) and not add excess salt or borax to my fruit trees.

Thanks in advance.

 

[DeeAnna]

Have you read any of the tutorials in the LS forum here? If not, you need to remedy that lack! There is absolutely no need to neutralize liquid soap with borax or citric acid or whatever. Look for Susie's CP liquid soap tutorial (a stand-alone tutorial) and Irish Lass' LS tutorial (in the Soapmaking 101 video thread).

As far as "excessively alkaline soap" ... you need to formulate your soap recipe properly (see tutorials) so it is slightly superfatted and that's as good as it gets. Do not expect to lower the pH below what is natural for liquid soap other that to ensure your recipe is properly formulated and the soap is properly made.

If you have hard water, any lye soap made with any type of fat, coconut or otherwise, will leave a film on skin or clothes. It's called hard water scum and it comes with the territory. If you want to reduce that, you need to consider adding a chelator such as sodium citrate or tetrasodium EDTA to your recipe.

 

[kchaystack]

there is a recent thread that talked about soapy water being good for plants also.

 

[LBussy]

Have a look here:

http://www.soapmakingforum.com/showthread.php?t=46114

Get yourself a drink and a snack, and read it all. For the thread that started it all, check out here:

http://www.thedishforum.com/forum/index.php?/topic/146547-glycerin-method-liquid-soap/

That one may take several trips to the kitchen but it's worth it.

I made my first liquid soap this past weekend, no borax, no issues other than the ones I created by being "smarter" than those that came before me.

 

[user 18839]

Thanks DeeAnna and LBussy - the specific recommendations on where to look are helpfu since there is so much on this site.
Slightly superfatted should be all I need since we haven't been getting a scum from the current laundry soap.

 

[liquidsoaplady]

Check out this link, it explains what borax is, boron a naturally occurring element. This may make you rethink it's effects on plants.



http://www.borax.com/about-borates/borates-by-nature



"People didn't know about mineral nutrients when they first started growing crops more than 10,000 years ago. In fact, it has only been in the last century that scientists and farmers discovered the seven essential micronutrients that plants need to grow, boron among them.



Boron performs at the cellular level, and is integral to a plant's reproductive cycle; controlling flowering, pollen production, germination, and seed and fruit development. The mineral also acts as a fuel pump, aiding the transmission of sugars from older leaves to new growth areas and root systems"



Just thought this was interesting, the borax, such as 20 Mule Team Borax, is just borax and oxygen, no additives.



https://www.omsi.edu/sites/all/FTP/files/kids/Borax-msds.pdf



The MSDS lists it as a non toxic substance.



I've never really ever understood the issue with Borax............

 

[LBussy]

Check out this link, it explains what borax is, boron a naturally occurring element. This may make you rethink it's effects on plants. [...] The MSDS lists it as a non toxic substance. [...] I've never really ever understood the issue with Borax............

I've never really ever understood the issue with Borax............

Steak is non-toxic too, yet I would not add it to soap just because it's not dangerous.

Borax is an anti-fungal. Therefore it could reasonably have an impact on micro fauna if dispersed without concern into a garden. As a matter of fact it can be used as a preventative against wood-rot (which is fungal in nature). It is less effective than say EDTA as a chelating agent. It is banned in the US for food use.

While it is used in agriculture, it is not a panacea. Over-use of any nutrient can have negative effects. A supplier of agricultural Boron indicates that testing should be done before use to determine if it is needed and at what rate. They also indicate over-application may reduce yields.

So given that there is no reason to add it to liquid soaps (as the above referenced body of knowledge seems to prove) and that haphazard release of chemicals may actually be a negative environmental impact, why use it? It does not neutralize liquid soap, it is more of a buffer, and we see that careful recipe calculation (as we do in in bar soap) results in a product that is not lye heavy.

 

[Seawolfe]

I agree with most of what you say Lee - but I DO add it to my laundry soap mix because it really does help with cleaning my clothes and other stuff.

I also use it for general outside cleaning and regularly dump the dregs on my plants with no issues. But if I noticed any issues I would simply dilute the grey water (if I didn't have really good settling tanks).

 

[LBussy]

I'm not judging ... I'm just pointing out that it's not a "no-brainer" and a person should not just assume that's it's fine just because it has an application in agriculture. The OP's question seemed to be surrounding neutralization in liquid soap which we now know is not necessary. The OP also did not want to add excess Borax, which seems to be a very reasonable desire.

 

[dosco]

Slightly superfatted should be all I need since we haven't been getting a scum from the current laundry soap.

What soap are you currently using? It's possible that it has a chelator which is why you aren't getting much scum.

Out of curiosity, how does one use greywater for laundry? Do you have a greywater plumbing system? Also, do you need to add bleach or other chemicals to the wash water to make sure it is (relatively) sanitary?

Just curious. I currently live on the east coast but have lived in N. California for a few years when I was younger.

-Dave

 

[user 18839]

I'm currently using a coconut oil soap made w/ sodium hydroxide (hard soap) that I melt down. I think our water is naturally fairly soft since I haven't had to clean our electric kettle once in the year & a half we've lived here. Other places I've lived, cleaning the scale from the kettle was a monthly task.

Our greywater has no holding tank - it's direct laundry to landscape. As such, we use it for our fruit trees, not veggies or food directly touching the soil. Apparently it's one of the few greywater systems you can put in w/o a permit here in CA provided you have an accessible three-way valve so you can go back on sewer should you need to (e.g. when I'm doing stained whites and using a ton of oxyclean - too much salt for the trees). My husband just googled to find plans - plenty of info available online about the system and the legality of it here in CA.

So I'm not using a ton of soap but figure the sodium will build up over time. I periodically add gypsum to the trees - both to dealkanize and to loosen our hardpan clay. But I would also just rather refigure the soap so that any build up is something the plants can use - hence moving to actual liquid soap w/ the potassium hydroxide. The threads above helped me figure out a formula - now I just need to find the time for the batch and to locate the potassium hydroxide (striking out at the hardware stores - probably need to order). . .