I have propylene glycol and want to make liquid soap in the lab. How do I do it?

Question

If possible, I'd like detailed methods on how to do it and also hoe to synthesize propylene glycol from glycerin/glycerol.

Answer 1

Propylene glycol (CH3CHOHCH2OH) is used as an additive to liquid soap mixtures. It is not usually used in making the soap itself. It generally is added at anywhere from one (1) to five (5) percent of the product, but some contain as high as ten (10) percent.

It is manufactured commercially by the hydration of propylene oxide which comes from petroleum refining. It is not usually made from glycerin.

What you would need to do is prepare a soap (like sodium stearate) and disolve this in water and add the propylene glycol to this mixture to make "liquid soap."