How is glycerol separated from spent-lye in the soap industry?

Which method is used to separate glycerol from spent lye in the soap industry?

Benzoic acid is an organic compound. Its crude sample can be purified by crystallisation from hot water. What characteristic differences in the properties of benzoic acid and the impurity make this process of purification suitable?

From the figure of column chromatography given below,identify the incorrect statements.
$A.$ Compound '$c$' is more polar than '$a$' and '$b$'
$B.$ Compound '$a$' is least polar
$C.$ Compound '$b$' comes out of the column before '$c$' and after '$a$'
$D.$ Compound '$a$' spends more time in the column
Choose the correct answer from the options given below :-

Glycerol is separated in soap industries by

Aniline is separated from a mixture by