Environmentally dependent adsorption of 2,4-dichlorophenol on cellulose-chitosan self-assembled composites

Area of Science:

• Materials Science
• Environmental Chemistry
• Green Chemistry

Background:

• Growing demand for sustainable, bio-based materials produced via eco-friendly methods.
• Need for effective adsorbents to remove widespread environmental pollutants like 2,4-dichlorophenol.

Purpose of the Study:

• To develop a green method for fabricating shape-controlled cellulose-chitosan hydrogel structures.
• To evaluate the adsorption efficiency of these structures for 2,4-dichlorophenol under varying pH conditions.
• To assess the adsorbent's regeneration capabilities.

Main Methods:

• Fabrication of cellulose dissolving pulp coated by chitosan into shape-controlled hydrogel structures.
• Adsorption experiments conducted at pH 5.5 and 9 using 2,4-dichlorophenol as the target pollutant.
• Testing of both hydrogel and dried hydrogel structures for adsorption capacity.
• Evaluation of adsorbent regeneration for both dry and never-dried states.

Main Results:

• Adsorption of 2,4-dichlorophenol was effective only at acidic pH (5.5) due to electrostatic interactions.
• The hydrogel structure achieved a high adsorption capacity of 905 ± 71 mg/g.
• Dried hydrogel structures showed a maximum adsorption capacity of 646 ± 50 mg/g.
• Successful regeneration of the adsorbent was demonstrated, with improved performance in the never-dried state.

Conclusions:

• Cellulose-chitosan hydrogels offer a tunable and effective platform for removing 2,4-dichlorophenol.
• The material's adsorption is pH-dependent, highlighting the potential for targeted pollutant removal.
• The adsorbent exhibits good regeneration properties, making it a sustainable option for wastewater treatment.