Enhanced dye sequestration with natural polysaccharides-based hydrogels: A review.

Area of Science:

• Environmental Science
• Materials Science
• Polymer Chemistry

Background:

• Industrial activities increase dye concentration in wastewater, necessitating effective removal methods.
• Adsorption is a practical decolorization technique due to low cost and high efficiency.
• Hydrogels, particularly natural polysaccharide-based ones, show promise for wastewater treatment owing to their unique properties.

Purpose of the Study:

• To investigate the use of natural polysaccharide hydrogels for sustainable dye removal from wastewater.
• To review the properties, preparation, and adsorption effectiveness of six specific biopolymers: chitosan, cellulose, pectin, sodium alginate, guar gum, and starch.
• To analyze the impact of hydrogel size and shape on dye adsorption rates.

Main Methods:

• Literature review of six natural polysaccharide hydrogels (chitosan, cellulose, pectin, sodium alginate, guar gum, starch).
• Analysis of their chemical structures, origins, characteristics, and applications.
• Evaluation of hydrogel preparation techniques, chemical modifications, and adsorption efficiencies.
• In-depth assessment of the influence of hydrogel size and shape on adsorption kinetics.

Main Results:

• Natural polysaccharide hydrogels are robust, biodegradable, non-toxic, and cost-effective alternatives to synthetic materials.
• The study details the manufacturing, modification, and adsorption performance of selected biopolymer hydrogels.
• Novel evaluation of how hydrogel size and shape influence dye adsorption rates was conducted.

Conclusions:

• Natural polysaccharide hydrogels present a sustainable and reproducible solution for industrial dye wastewater treatment.
• Further research is needed to address hydrogel limitations and explore future applications in dye removal.
• The findings provide insights for optimizing hydrogel-based adsorption systems and identifying research gaps.