Advanced Separation Process

A batch rectification column with a separation capability equivalent to 2 ideal stages is configured to operate with a constant reflux ratio of 6:1. This rectification column is used for solvent composition and solute concentration adjustment between two reaction steps in a binary solvent system with a relative volatility that can be taken to be 3.5. The solute can be assumed to be non-volatile, inert and not to impact upon the relative volatility of the binary solvent system for the purposes of this analysis. The charge to the rectification column can be taken to be 100kmol of total solvent, for the purpose of the analysis the presence of the solute and influence on concentration may also be ignored. For the reaction following the distillation to function correctly the concentration of the more volatile solvent component must be reduced from 40mol% to 20mol% within the rectification step, where impact of solute on mol% is ignored. i) How much distillate must be removed to achieve this adjustment in solvent composition? A constant reflux ratio of 2:1 is also available with this rectification column. ii) What is the percentage change in total distillate that must be removed from the column to make the same adjustment from 40mol% to 20mol% of the more volatile component? iii) What is the percentage time change in distillation time needed with the change in reflux ratio, in making the composition adjustment for the binary solvent system (40 mol% to 20mol% ) with the adjusted reflux ratio (2:1)? Assume a constant boil-up rate of 5kmol/min