Acid properties studies of Si and Alsingle bondSi oxide pillared Zrsingle bondTi phosphates Original Research Article

Acid properties of Tisingle bondZr phosphates pillared with silica and silica-alumina oligomers have been studied by following the adsorption-desorption of several probe molecules with different acid strengths (NH3, pyridine and isopropanol). Samples showed similar acid properties, but other than the well known acidic materials like amorphous silica-aluminas and zeolites as determined by NH3 adsorption. FT-IR studies of absorbed pyridine showed the existence of Lewis and Brönsted sites on silica-alumina pillared material whereas no Lewis sites were detected on the silica-pillared counterparts. By isopropanol decomposition it was shown that in the range of temperatures analyzed, acid centres reacted. The activity of the material in isopropanol decomposition reaction is high, with values ranging between 30 and 40 μmol g−1 s−1 for the catalyst derived from samples with higher silica-alumina loading.