Preparation, characterization and adsorption performance of a novel anionic starch microsphere

Area of Science:

• Materials Science
• Environmental Chemistry
• Polymer Science

Background:

• Developing efficient adsorbents for water pollutant removal is crucial.
• Starch-based materials offer a sustainable and biodegradable platform for adsorbent synthesis.
• Anionic starch microspheres (ASMs) were synthesized for potential environmental applications.

Purpose of the Study:

• To synthesize and characterize anionic starch microspheres (ASMs).
• To investigate the adsorption performance of ASMs for methylene blue (MB) removal.
• To determine the adsorption equilibrium and kinetics of MB onto ASMs.

Main Methods:

• Neutral starch microspheres (NSMs) synthesized via inverse microemulsion.
• ASMs prepared from NSMs using chloroacetic acid.
• Characterization using FT-IR, SEM, and particle size analysis.
• Adsorption studies conducted by varying time, MB concentration, and temperature.
• Adsorption data fitted to Langmuir, Freundlich, pseudo-first-order, and pseudo-second-order models.

Main Results:

• Synthesized ASMs exhibited compact structure, high hardness, and an average diameter of approximately 75 micrometers.
• ASMs demonstrated effective removal of methylene blue from aqueous solutions.
• Adsorption equilibrium data best fit the Langmuir isotherm model.
• Adsorption kinetics were accurately described by the pseudo-second-order model.
• Temperature had a negligible impact on MB adsorption by ASMs.

Conclusions:

• Anionic starch microspheres are effective adsorbents for methylene blue.
• The adsorption process is well-described by Langmuir isotherm and pseudo-second-order kinetics.
• ASMs show promise for the removal of organic dyes from wastewater.