Question

A liquid stream has a flow rate of 100 mol/min and contains 25 mol% Stanzium and 75 mol% water. Stanzium is foul and disgusting and nobody wants that stuff in their water, so an extraction process is used to purify the water. The liquid enters the extraction unit, as does 400 mol/min of a solvent stream, which contains 98 mol% hexane and 2 mol% Stanzium. The water and hexane are completely immiscible, though the Stanzium is soluble in both.

The product leaving the extraction unit is 99 mol% water and 1 mol% Stanzium. The spent solvent leaving the extraction unit contains no water- only Stanzium and hexane. It proceeds to a distillation column, in which the hexane and Stanzium are separated. The top product from the distillation column is pure Stanzium. The bottom product is 98mol% hexane and 2mol% Stanzium, and this is the solvent stream that is recycled to the extraction unit. Both units operate at steady state.

Determine the flow rate of the pure Stanzium that leaves the distillation column.

Determine the total molar flow rate, and the mole fraction of Stanzium, in the spent solvent that leaves the extractor.

Answer 1