Removal of Different Dye Solutions: A Comparison Study Using a Polyamide NF Membrane

Area of Science:

• Environmental Science
• Chemical Engineering
• Materials Science

Background:

• Organic dyes from industrial processes pose a significant threat to aquatic ecosystems by inhibiting photosynthesis.
• Effective removal of these dyes is crucial for environmental protection and water quality management.

Purpose of the Study:

• To investigate the feasibility of using nanofiltration for removing small organic dyes from aqueous streams.
• To evaluate the performance of the NF99 nanofiltration membrane with various dye molecules.

Main Methods:

• Selected six organic dyes (Acid Brown-83, Allura Red, Basic Fuchsin, Crystal Violet, Methyl Orange, Sunset Yellow) with similar molecular volumes.
• Employed the NF99 nanofiltration membrane to assess permeate flux and rejection coefficients.
• Conducted microscopy and membrane behavior analysis, and applied the Spiegler-Kedem-Katchalsky model.

Main Results:

• The NF99 membrane demonstrated varying rejection coefficients and permeate flux rates depending on dye characteristics.
• Microscopy revealed membrane behavior after exposure to the largest dye molecule.
• The Spiegler-Kedem-Katchalsky model successfully simulated the membrane's dye elimination performance.

Conclusions:

• Nanofiltration using the NF99 membrane is a viable method for removing small organic dyes from water.
• Membrane performance is influenced by dye size, shape, and charge.
• The Spiegler-Kedem-Katchalsky model provides a useful simulation tool for predicting nanofiltration efficiency.