Amino-functionalized SBA-15 mesoporous silicas as sorbents of platinum (IV) ions

Amino-functionalized mesoporous silicas were synthesized by co-condensation of tetraethoxysilane (TEOS) and aminopropyltriethoxysilane (ATES) or N-[3-(trimethoxysilyl)propyl]ethylenediamine (TMPD) in the presence of Pluronic P123 block copolymer. The obtained materials have well-developed porous structures – the values of specific surface area are in the range of 740–840 m2/g, and the sizes of cylindrical mesopores are in the range of 6.5–6.8 nm. A few instrumental techniques were used to characterize structure, morphology and composition: XRD, nitrogen sorption measurements, elemental analysis, FTIR, 29Si NMR XPS, TEM. The obtained organosilicas were used as sorbents of Pt(IV) ions. Batch adsorption studies were carried out with various parameters, such as initial metal ion concentration, contact time and pH. Desorption experiments were also performed to examine possibility of quantitative recovery of bound platinum ions.