Effective removal of Cu(II) from water by three-dimensional composite microspheres based on chitosan/sodium alginate/silicon dioxide: Adsorption performance and mechanism

Chitosan (CS) is commonly used as an adsorbent for removing Cu(II) from water, but it has drawbacks such as solubility in dilute acid, difficulty in recycling in powder form, and short service life. This study utilized sodium alginate (SA) as a gel carrier to encapsulate CS, combined with silicon dioxide (SiO