Sheet $2$: Liquid $-$ Liquid Extraction

Acetaldehyde $(5\%$ by wt$.)$ is in solution in toluene and is to be extracted with water in a five$-$stage co$-$current unit. If $25kg$ of water is added to each stage, determine:

a$)$ The final raffinate concentration and amount.

b$)$ The total amount of acetaldehyde extracted.

c$)$ The amount and concentration of raffinate and extract from the third stage.

If $Y=kg$ acetaldehyde $\frac{?}{kg}$ water, $x=kg$ acetaldehyde $\frac{?}{kg}$ toluene, then $Y_e=2\mathrm{.}2x$ represents the equilibrium relation. Assume the feed is $100kg.$