Mass Transport of Dye Solutions through Porous Membrane Containing Tannic Acid/Fe³⁺ Selective Layer

Area of Science:

• Materials Science
• Chemical Engineering
• Membrane Science

Background:

• Tannic acid (TA)-Fe³⁺ membranes offer sustainable fabrication, high water flux, and effective organic solute rejection.
• Understanding solute transport mechanisms is crucial for optimizing membrane performance in water treatment.

Purpose of the Study:

• To describe the transport of aqueous dye solutions through TA-Fe³⁺ membranes using the Spiegler-Kedem-Katchalsky (SKK) model.
• To estimate the reflection coefficient (σ) and solute permeability (PS) to predict solute retention.
• To validate the SKK model's predictive capabilities for dye rejection.

Main Methods:

• Utilized the Spiegler-Kedem-Katchalsky (SKK) model to analyze dye transport.
• Estimated reflection coefficient (σ) and solute permeability (PS) from non-linear model equations.
• Validated model predictions against experimental data across various conditions.

Main Results:

• SKK model parameters (σ and PS) were found to depend on dye molecular size and charge.
• Simulated dye rejections closely matched experimental results.
• Model validation confirmed its effectiveness at various feed concentrations and low permeate fluxes.

Conclusions:

• The SKK model provides valuable insights into the mass transport of dye solutions through TA-Fe³⁺ membranes.
• The model enables accurate prediction of dye rejection by TA-Fe³⁺ selective layers in TFC membranes.
• This study enhances understanding of membrane-based dye removal processes.