Silica–titania sol–gel hybrid materials: synthesis, characterization and potential application in solid phase extraction

The biphenilaminepropylsilica and biphenilaminepropylsilicatitania were synthesized by sol–gel method, in two steps: (a) biphenylamine reacts with chloropropyltrimethoxysilane and (b) the product of reaction was polycondensed with tetraethylorthosilicate (TEOS) or TEOS and titanium isopropoxide. The sol–gel materials were characterized using infrared spectroscopy and N2 adsorption–desorption isotherms and they were employed as sorbents for carcinogenic N-containing compound retention, in aqueous solution, using the SPE technique. The N-containing compounds adsorption was influenced by the titania presence and the sorption process seems to happen in the pores with higher organic density.