Polydopamine/montmorillonite-embedded pullulan hydrogels as efficient adsorbents for removing crystal violet

Area of Science:

• Materials Science
• Environmental Chemistry
• Polymer Science

Background:

• Dye wastewater treatment faces challenges with secondary pollution and weak adsorbent mechanical strength.
• Existing adsorbents often lack the durability and reusability required for industrial applications.

Purpose of the Study:

• To develop a robust and eco-friendly composite hydrogel adsorbent for efficient dye removal.
• To investigate the structure-property-performance relationship of the synthesized adsorbent.
• To address limitations of current adsorbents in dye wastewater treatment.

Main Methods:

• Synthesized a pullulan-based hydrogel incorporating polydopamine (PDA) and montmorillonite (MMT).
• Characterized adsorbent properties using Fourier-transform infrared spectroscopy and scanning electron microscopy.
• Evaluated dye adsorption capacity, kinetics (Langmuir isotherm, pseudo-second-order), and mechanical strength.

Main Results:

• The composite hydrogel (PM3) exhibited a maximum adsorption capacity of 112.45 mg/g for dyes.
• Adsorbent properties, including mechanical strength and swelling, were tunable via the PDA/MMT ratio.
• The adsorbent demonstrated excellent mechanical strength and avoided secondary pollution.

Conclusions:

• The PDA-MMT/pullulan composite hydrogel is a promising adsorbent for dye wastewater treatment.
• Its tunable properties, high capacity, and mechanical robustness offer practical advantages.
• This adsorbent presents a sustainable approach to mitigating textile industry pollution.