Effect of SH/SBA‐15 Molar Ratio on Pb(II) and Cd(II) Ions Adsorption from Aqueous Solution by Mercaptopropyl‐grafted SBA‐15 Mesoporous Material as Adsorbent

The purposes of the current study were to investigate the adsorption of Pb(II) and Cd(II) from aqueous solution by thiol‐functionalized SBA‐15 materials designed by SBA‐15‐SH (x) where x is the SH/SBA‐15 molar ratio, which corresponds to the introduced moles number of Mercapto moieties to that of siliceous of the SBA‐15 materials. Furthermore, these materials were synthesized using 3‐Mercaptopropyltrimethoxysilane (MPTMS) via post‐grafting approach. SBA‐15‐SH(x) materials were characterized by XRD, N 2 adsorption‐desorption and FT‐IR. The incorporation of SH fragments was proved by FT‐IR Spectroscopy, thermogravimetric analysis (TGA) and solid state 13 C and 29 Si NMR Spectroscopy. The removal of lead ions is more important than that of cadmium ions. Furthermore, the lead removal on SBA‐15‐SH(x) increased with the increase of SH/SBA‐15 molar ratio (removal rate of 28.5, 71.3, and 96.8 % for SH/SBA‐15 molar ratio=0.35, 0.7 and 1.4, respectively) while the removal of cadmium was not affected (around 57 % removal rate for all molar ratios).