Cationic surface-modified regenerated nanocellulose hydrogel for efficient Cr(VI) remediation

Area of Science:

• Materials Science
• Environmental Science
• Chemical Engineering

Background:

• Nanocellulose is a promising eco-friendly water treatment material due to its large surface area and hydroxyl groups.
• Challenges include nanocellulose's dispersion state and poor performance in removing anionic pollutants.
• Developing practical, high-performance nanocellulose-based materials is crucial for water remediation.

Purpose of the Study:

• To fabricate a robust and efficient water treatment material from cellulose.
• To overcome the limitations of using nanocellulose in its native form for water purification.
• To enhance the pollutant removal capacity, particularly for anionic contaminants.

Main Methods:

• Fabrication of regenerated cellulose (RC) hydrogel via dissolution and regeneration using an eco-friendly solvent.
• Surface modification of RC with polyethyleneimine (PEI) coating through a crosslinking process to introduce cationic functional groups (P/RC).
• Evaluation of the P/RC material's mechanical properties and performance in removing hexavalent chromium (Cr(VI)).

Main Results:

• The PEI surface cationization significantly improved the mechanical rigidity of the RC hydrogel.
• The P/RC material exhibited an excellent Cr(VI) removal capacity of 578 mg/g.
• The P/RC maintained over 90% removal efficiency after seven reuse cycles, demonstrating its stability and reusability.

Conclusions:

• The developed P/RC hydrogel is a mechanically robust and highly effective material for removing toxic Cr(VI) from water.
• The cationization strategy successfully addresses the limitations of anionic nanocellulose materials.
• This regenerated cellulose-based material shows significant potential for practical applications in wastewater treatment.