Saponification Reactions
Saponification, one of the great organic reactions known to ancient man. In this, long chain acids are neutralised with an akali hydroxide to form
that salt and glycerol. The acid salt is precipated using NaCl, and you have crude soap. Clean your clothes and be happy.
These acids (henceforth known as fats, for simplicity) are widely avalible in a number of forms; oils, butters, greases, whatever. Hydroxides are
avalible as lye, or can be prepared by the conventional cave-man method, or the electrolysis of an akali-chloride in water.
Chances are, all of the above information was known to you, as that was backround stuff. Onward to the slightly more interesting.
Widely avalible is a table of saponification values, this is essentially the ratio of fat/hydroxide needed to complete the saponification reaction.
For example, soybean oil is .1350 when using NaOH.
I saponificated some salted butter, as no non-salted butter was avalible, non-salted would be ideal. This would keep the soap from precipating when
you dont want it to, and just make things cleaner. I measured 57g of salted butter, and 10g of NaOH. I melted the butter in a beaker and added the
NaOH. I stirred, not much happened. I placed it in a hot water bath for about 10 minutes, while stirring occasionally, and there was a visible change
in the reaction, some crude orangish stuff had precipated. This was now placed in a cold water bath with ice, and after it had all solidified, there
were 2 distinct layers of nearly equal proportions. On top, a lightly yellow colored solid layer, resembling soap. On the bottom was the orange stuff.
I have yet to do anything more.
To make the acids themselves, you could add HCl and then distill them apart, or use the mix. Ethyl butyrate is what makes pinapples smell the way they
do, but butyric acid smells terrible.
That was a relitively short, and not very organised start to the thread. I don't know what anyone else thinks, but it was rather spurious, I felt like
doing some chemistry.
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