Application of nanocellulose in water treatment and adsorbent materials: green and efficient emerging adsorbents

Application of nanocellulose in water treatment and adsorbent materials: green and efficient emerging adsorbents

With the acceleration of industrialization, the problem of water resource pollution is becoming increasingly serious, and traditional water treatment materials face challenges such as poor sustainability, low selectivity and high treatment costs. In recent years, Nanocellulose has become an important candidate for the new generation of water treatment adsorbent materials due to its renewability, rich surface functional groups, high specific surface area and good mechanical properties .

1. The structure and adsorption potential of nanocellulose

Nanocellulose is a material obtained by mechanical, chemical or biological nanoification of natural cellulose, mainly including three forms:

Cellulose nanofibers ( CNF )

Cellulose nanocrystals ( CNC )

Bacterial cellulose ( BC )

Its surface contains a large number of hydroxyl groups, and functional groups such as carboxyl groups, sulfonic acid groups, amino groups, and quaternary ammonium groups can be further introduced to enhance the adsorption capacity of different pollutants (such as heavy metal ions, organic dyes, oils, and drug residues).

2. Functional modification enhances adsorption performance

Chemical modification can effectively improve the affinity of nanocellulose for specific pollutants. Common modification methods include:

Modification method	Introduce groups	Applicable pollutants
TEMPO oxidation	-COOH	Heavy metals such as Pb²⁺, Cu²⁺, Cd²⁺ and other
Sulfation treatment	-SO₃H	Cationic dyes, heavy metals
Aminolysis	-NH₂	Organic acid, anionic dyes
Graft polymerization	Contains functional monomers	Special drug residues, pesticides, etc.

The modified nanocellulose forms a three-dimensional porous structure, which not only improves the adsorption capacity, but also has faster adsorption kinetic characteristics.

3. Typical application scenarios

The modified nanocellulose removal of heavy metal ions
has a significant adsorption effect on 、Pb²⁺ 、Hg²⁺ Cr⁶⁺ etc., and is suitable for the treatment of mining and metallurgical wastewater.

Dye wastewater treatment
nanocellulose membrane or hydrogel can efficiently adsorb cationic / anionic dyes (such as methyl blue, Congo red), and are suitable for printing and dyeing, textile and other industries.

Oil-water separation and emulsion removal
of hydrophobic modified nanocellulose membranes can achieve efficient oil-water separation and are used for the purification of catering oil stains and industrial emulsions.

Antibacterial filtration and micropollution control
are combined with nanosilver, titanium dioxide, etc., giving nanocellulose sterilization, anti-fouling and other functions, and are suitable for domestic water and medical water source purification.

Drug and pesticide residue adsorption
has good adsorption properties for sulfonamide and tetracycline antibiotics, and can be used for the purification of agricultural discharge water.

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4. Performance comparison and advantage analysis

Performance metrics	Nanocellulose	Activated Carbon	Polymer adsorbents
source	Renewable resources	No regeneration	Petrochemical raw materials
Adsorption rate	快	中	中
Surface modification	强	generally	generally
Biodegradability	好	差	差
Application flexibility	High (membrane, gel, etc.)	Low (granules /powder)	中

5. Future development direction

Intelligent responsive adsorption materials
develop pH/ temperature responsive nanocellulose composite materials to achieve selective adsorption and regeneration.

Industrial large-scale preparation
optimizes green preparation technology, reduces costs, and promotes the industrial application of nanocellulose in water treatment.

The construction of multifunctional collaborative system is
combined with the technology of photocatalysis, electrosorption, etc. to develop a composite purification system to achieve efficient water purification and resource recycling.

6. Conclusion

Due to its green, diverse functions and superior adsorption performance, With the continuous optimization of material design, preparation costs and application technologies, nanocellulose will play an increasingly important role in industrial wastewater treatment, drinking water purification, and environmental restoration.nanocellulose is gradually replacing traditional adsorption materials and becoming an important member of high-performance water treatment materials.