In a single stage extraction process, 10 kg of pure solvent S (containing no solute A) is mixed with 30 kg of feed F containing A at a mass fraction xf = 0.2. The mixture splits into an extract phase E and a raffinate phase R containing A at xB = 0.5 and xR = 0.05 respectively. The total mass of the extract phase is (in Kg) ?

Question

Accepted Answer

8.89. Use mass balance on solute A: $F 	imes x_f = E 	imes x_E + R 	imes x_R$. Also use total mass balance: $F+S = E+R$. Solving these equations yields the extract mass as 8.89 kg.