Electrospun lignin-based composite nanofiber membrane as high-performance absorbent for water purification

Area of Science:

• Materials Science
• Environmental Science
• Polymer Chemistry

Background:

• Wastewater contamination by dyes is a significant environmental concern.
• Developing efficient and cost-effective adsorbents for dye removal is crucial.

Purpose of the Study:

• To fabricate and characterize a novel alkali lignin/poly (vinyl alcohol) (lignin/PVA) composite nanofiber membrane.
• To evaluate its performance as an adsorbent for Safranine T (ST) dye removal.
• To investigate the influence of various parameters on adsorption and desorption behavior.

Main Methods:

• Fabrication of lignin/PVA composite nanofiber membranes via electrospinning.
• Characterization of membrane morphology and chemical properties.
• Adsorption experiments varying initial dye pH, time, and temperature.
• Langmuir isotherm and pseudo-second-order kinetic modeling.
• Desorption and recycling studies.

Main Results:

• Strong intermolecular hydrogen bonds formed between lignin and PVA.
• Bead-free membranes with decreased fiber diameter were achieved with up to 50 wt% lignin.
• Adsorption capacity increased with initial dye pH and temperature.
• Adsorption followed Langmuir isotherm and pseudo-second-order kinetics.
• Excellent desorption and recycling performance was observed.

Conclusions:

• The lignin/PVA composite nanofiber membrane is a highly effective adsorbent for Safranine T.
• The material demonstrates significant potential for cost-efficient dye removal from wastewater.
• The study highlights the synergistic interaction between lignin and PVA in enhancing adsorption properties.