Glycerol and spent lye clarification - Illinois Institute of Technology

solution. Chloridea may be removed by the
addition of some soluble silver salt such as
the nitrate, or the oxide, silver chloride
being precipitated and filtered from the
solution.
Proteins and some other organic substances
can often be removed completely by precipitat-
ing the slightly alkaline solution with zinc
chloride. The precipitate is filtered off
and the filtrate rendered slightly acid when
further precipitation will often occur.
The last traces of zinc may be removed from
the solution by adding potassium ferrocyanide,
which is also a very good precipitant of
albumen.
At the present writing there seems to be
no accurate method for the determination of
glycerol of all percentages in complex
mixtures. In aqueous solutions glycerol can
be determined accurately by means of specific
gravity and refractive index, Lenz recommends
that the refractive index of glycerol solution
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