Nanotubular titanate supported palladium catalysts: The influence of structure and morphology on phenol hydrogenation activity

Abstract Nanotubular titanates were synthesized by a simple methodology using a commercial TiO 2 (Degussa P25 containing anatase and rutile phases) and a base (KOH) solution. Prior to the removal of KOH, the samples of TiO 2 were aged for three different time intervals (0, 2, 61 days). The freshly prepared synthetic samples were characterized for their structural and morphological properties by BET, XRD, Raman, TEM, HRTEM, EDX and SEM. Both TEM and SEM analysis revealed that ageing time influenced the tubular structure and morphology of the new materials. Raman and surface analysis data also showed that ageing time affected both the structural and surface properties of TiO 2 . The XRD results indicated that the crystallinity of the TiO 2 decreased with increasing ageing time. Energy dispersive X-ray spectroscopy (EDX) showed that the tubes derived from TiO 2 are comprised of potassium, titanium and oxygen. Catalysts A, B and C were prepared by the addition of 1 wt% Pd (wet impregnation) to the titanate formed by ageing TiO 2 in KOH for 0, 2 and 61 days, respectively and revealed Pd particle sizes of