A storage tank contains a heavy organic liquid. Chemical analysis shows the liquid to contain 600 ppm (molar basis) of water. It is proposed to reduce the water concentration to 50 ppm by boiling the contents of the tank at constant atmospheric pressure. Because the water is lighter than the organic, the vapor will be rich in water; continuous removal of the vapor serves to reduce the water content of the system. Estimate the percentage loss of organic (molar basis) in the boil-off process. Comment on the reasonableness of the proposal.

Suggestion: Designate the system water(1)/organic(2) and do unsteady-state molar balances for water and for water + organic. State all assumptions.

Data: ^Tn₂ = normal boiling point of organic = 130°C.

γ^∞₁ = 5.8 for water in the liquid phase at 130°C.