Due to population growth and global warming, water treatment is required. In this study, we investigated the characterization, examination, and adsorption capacity of sodium alginate (SA) covalently crosslinked with a diethylenetriamine-triazine-sulfonamide porous framework (DTTS-POP) using a benzene-1,3-disulfonylchloride linker. For this purpose, DTTS-POP was synthesized by reacting diethylene diamine, triazine monomers, benzene-1,3-disulfonylchloride, and SiO2 NPs as a sacrificial template. In the next step, SA was immobilized using a benzene-1,3-disulfonylchloride linker to synthesis sodium alginate/diethyleneamine-triazinesulfonamide (SA/DTTS-POP). Consequently, the adsorption capacity and reaction rate were increased by increasing the number of mesoporous structures, accessible active sites, and amphiphilicity upon polysulfonamide (PSA) engineering. The synthesized composite was characterized by FT-IR, XRD, FESEM, TEM, EDX, elemental mapping, TGA, and BET. In this respect, central composite design (CCD) was utilized to minimize the number of the reaction parameters (i.e., temperature, initial pH, and adsorbent concentration). According to the experimental results of this study, SA/DTTS-POP provides better efficiency and shorter reaction time than methyl violet in Pb(II) removal. The highest adsorption capacity was 229.2 mg/g and 168.1 mg/g for Pb(II) and methyl violet, respectively. Furthermore, the SA/DTTS-POP was recycled conveniently and reused several times in succession with no remarkable loss in its reactivity
