Question

The McCabe-Thiele method used to find the number of theoretical stages required in a distillation operation is based on the assumption(s) that:

• A. liquid/vapour loading in each section of the tower remains constant
• B. Trouton's rule is applicable
• C. sensible heat differences are small because the temperature change from tray to tray is small
• D. liquid mixture forms an azeotrope

Hint:

The McCabe-Thiele method is based on simplifying assumptions like constant liquid/vapour load, small sensible heat differences, and applicability of Trouton's rule.

Answer 1

The Correct Option is A, B, C

Step 1: Comprehend the McCabe-Thiele methodology.
The McCabe-Thiele method facilitates the calculation of the theoretical stages needed in a distillation column. The underlying assumptions are:- (A) Constant liquid/vapour loading: This principle posits that liquid and vapour molar flow rates remain consistent throughout the tower sections.- (B) Applicability of Trouton's rule: Trouton's rule is pertinent for estimating the heat of vaporization, a common element in distillation computations.- (C) Negligible sensible heat differentials: This assumption, based on small tray-to-tray temperature variations, simplifies the temperature profile across the column.- (D) Azeotrope formation in liquid mixture: This is an extraneous assumption; the McCabe-Thiele method is applicable to systems that do not exhibit azeotrope formation.

Final Answer: \[\boxed{\text{A, B, C}}\]