A solution containing 7% acetaldehyde and 93% toluene is to be extracted with water in a 6-stage crosscurrent extraction unit to extract acetaldehyde. Toluene and water are essentially insoluble. If 30 kg of water each time are used per 120 kg of feed, calculate the amount of acetaldehyde extracted and the final concentration of the exit solution. The equilibrium relationship is given by: Y = 2.75 X

Y = kg acetaldehyde / kg water

X = kg acetaldehyde / kg toluene

All % are on weight basis