Residual Chlorella-Based Cellulose Nanofibers and Their Quaternization Modification and Efficient Anionic Dye...

Area of Science:

• Materials Science
• Environmental Science
• Biotechnology

Background:

• Anionic dyes are common industrial pollutants posing environmental and health risks.
• Nanocellulose, particularly from Chlorella algae, shows promise for wastewater treatment due to its cellulose content.
• Developing efficient adsorbents for dye removal is crucial for environmental protection.

Purpose of the Study:

• To prepare and evaluate cellulose nanofiber (CNF) and cationic cellulose nanofiber (CCNF) derived from Chlorella for dye adsorption.
• To investigate the adsorption kinetics, isotherms, and influencing factors (concentration, pH) for Congo red (CR) dye removal.
• To compare the adsorption capacities of CNF and CCNF for anionic dyes.

Main Methods:

• Homogenization was used to prepare CNF and quaternized CCNF from residual Chlorella.
• Congo red (CR) was used as a model anionic dye to test adsorption.
• Adsorption experiments were conducted to analyze kinetics, isotherms, and the effects of CR concentration and pH.

Main Results:

• Adsorption equilibrium was reached within 100 minutes, following pseudo-secondary kinetics.
• Adsorption capacity increased with CR initial concentration up to 40 mg/g.
• The Langmuir model best described the adsorption, indicating uniform surfaces and monolayer adsorption.
• Acidic conditions favored CR adsorption, especially for CCNF.
• CCNF exhibited a significantly higher maximum adsorption capacity (1657.89 mg/g) than CNF (190.0 mg/g).

Conclusions:

• Residual Chlorella-based CCNF is a highly promising adsorbent for removing anionic dyes from wastewater.
• CCNF's surface quaternization enhances its adsorption efficiency for anionic pollutants.
• This study highlights the potential of algal biomass-derived nanomaterials in sustainable wastewater treatment.