Construction of a double-layered polyelectrolyte-coated mesoporous silica containing residues of biogenic aspartic acid and its utilization for cadmium (II) removal

Highly efficient porous adsorbent has been developed by simple and inexpensive surface modification of mesoporous SBA-15 via an alternate adsorption of cationic poly(diallyldimethylammonium ion) and anionic poly(diallylaspartate). The nature of the charge on the surface after modification was confirmed by Zeta potential measurement. The surface morphology, topography, and its textural properties were examined by atomic force microscopy (AFM) and Nitrogen adsorption/desorption, respectively. TGA has been performed to ascertain the amount of polymer layer on the silica material. Multi-parameter isotherm models were used for the analyses of experimental data. The new protocol is found to be very impressive in the removal of toxic Cd(II) pollutant with an experimental maximum uptake capacity of 160 mg g ^–1 . [Figure not available: see fulltext.]