I agree with Susie that sodium hydroxide doesn't necessarily cause soap to be cloudy or opaque. It's more the fats used (stearic, palmitic) and the solvents (water, alcohol, sugar, glycols, etc.) that affect clarity. Couple of examples -- I recently dissolved a grated up bar of olive oil (castile) soap in distilled water. I wanted to make a gel soap to use when wet-felting wool. I had made the original soap using only 100% NaOH, olive, and distilled water. The resulting gel isn't liquid -- it's more like firm Jello dessert -- but it is as clear as if it was a KOH-olive-water soap. The original Pears soap was an NaOH soap that was then dissolved in ethanol. The ethanol was allowed to slowly evaporate off, leaving a transparent soap behind.
But there's another aspect to the issue Galaxy wrote. The sodium may not be causing the problem; the citrate may be. I wrote on September 14th in the "Sodium citrate from baking soda and citric acid" thread about the same issue Galaxy is referring to -- adding sodium citrate to diluted LS DOES cloud the soap and cause separation. I don't have an answer to this issue, and I'm glad to finally hear I'm not the only one with the problem.
Here's what I wrote in
Post 100 of that thread:
"I was wanting to use my homemade citrate to see how citrate controls soap scum created by mixing hard water from our well with my liquid soap. I wanted to add these results to the thread I started here:
http://www.soapmakingforum.com/showthread.php?t=52456. Problem is, when I added the citrate to the water and soap solution, the citrate "broke" the soap so I ended up with scummy water that had a layer of fatty acid on the surface.
"Thinking perhaps I had an excess of citric acid still left in the solution, I added a bit extra baking powder to ensure the acid was fully reacted to citrate. Tried the test again. Same results. Added a bit of citrate solution to just the liquid soap -- no added water -- and the mixture of citrate and the (originally transparent) LS turned an opaque white.
"I'm stumped. My understanding has been that citrate works pretty well to chelate metals and reduce soap scum, and I haven't been hearing people complain about citrate "breaking" their soap. You other soapy chemistry geeks out there -- what am I missing? Suggestions and thoughts are most appreciated."
Source:
http://www.soapmakingforum.com/showpost.php?p=544929&postcount=100
Edited 7 June 2016 to add -- I found the reason why my LS was turning white and separating when I added sodium citrate. I had made this citrate by reacting citric acid and baking soda to make a citrate solution. This solution also had excess baking soda in it, and it was the soda that was breaking down the soap. Sodium citrate without any excess baking soda (either bought commercially or made more carefully) works just fine -- no cloudiness and no separation.
