1. What is Raffinate Phase Solute Concentration?

Definition: This calculator determines the mass fraction of solute remaining in the raffinate phase after N stages of liquid-liquid extraction.

Purpose: It helps chemical engineers design and optimize multi-stage extraction processes for separation applications.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( X_N \) — Mass fraction of solute in raffinate after N stages
• \( F' \) — Solute-free feed flowrate (kg/s)
• \( E' \) — Solute-free extract phase flowrate (kg/s)
• \( K_{Solute} \) — Distribution coefficient of solute
• \( N \) — Number of equilibrium extraction stages
• \( z_C \) — Mass fraction of solute in the feed

Explanation: The formula calculates the progressive reduction in solute concentration through multiple extraction stages.

3. Importance of This Calculation

Details: Accurate prediction of raffinate concentration is crucial for designing efficient separation processes and meeting product purity requirements.

4. Using the Calculator

Tips: Enter all required parameters with appropriate units. The feed mass fraction (z_C) must be between 0 and 1.

5. Frequently Asked Questions (FAQ)

Q1: What is the distribution coefficient?
A: It's the ratio of solute concentration in extract phase to raffinate phase at equilibrium.

Q2: How does number of stages affect the result?
A: More stages typically lead to lower solute concentration in raffinate (better separation).

Q3: What are typical values for K_Solute?
A: This varies widely (0.1-10+) depending on solute and solvent system.

Q4: Why use solute-free flowrates?
A: This simplifies calculations by focusing on the carrier and solvent flows.

Q5: When is multi-stage extraction needed?
A: When single-stage can't achieve desired separation efficiency or purity.