Synthesis of Ionic Liquid-SBA-15 Composite Materials and Their Application for SO2 Capture from Flue Gas

A series of 1,3-bispropyltriethoxysilane-imidazolium chloride (FILs)-modified SBA-15 adsorbents have been prepared, characterized, and applied in SO2 capture for the first time. At low FILs loadings, significant levels of grafting were observed, while higher loading levels resulted in retention of a greater fraction of FILs precursors, as evidenced by FTIR spectroscopy. Textural properties gradually declined as FILs content increased, in conjunction with an apparent change in the regular nature of the SBA-15 pore structure and bulk particle morphology, as demonstrated by XRD, TEM, and SEM. SO2 adsorption breakthrough curves indicated that all materials possessed rapid and facile adsorption properties, with t0.9 values 1–2 orders of magnitude lower than those obtained over comparable materials under more favorable conditions. The largest total SO2 adsorption was achieved over 10%FILs@SBA-15, which exhibited a maximized FILs adsorption contribution that remained constant at higher loadings. Corrections agai...