Table 1.

Summary of various chitosan/alginate-based sorbent materials reported in the literature for the removal of SO₄²⁻ species from aqueous solution.

Adsorbent	Year	References
Chitin-based shrimp shells	2003	Moret and Rubio [53]
Biopolymeric alginate/clinoptilolite pellets	2009	Chmielewská et al. [54]
Protonation modified chitosan	2014	Guo et al. [55]
Chitosan-grafted-polyacrylamide	2015	Fosso-Kankeu et al. [56]
Chitosan-bentonite composite	2016	Mbakop et al. [6]
Chitosan flakes	2018	Schwarz et al. [57]
Magnetic chitosan microspheres	2019	Tian et al. [58]