Synthesis, characterization and catalytic testing of a 3-D mesoporous titanosilica, Ti±TUD-1 Z. Shan a, * , J.C. Jansen a , L. Marchese b , Th. Maschmeyer a a Applied Organic Chemistry and Catalysis, DelftChemTech, Delft University of Technology, Julianalaan 136, NL-2628 BL Delft, Netherlands b Dipartimento di Scienze e Tecnologie Avanzate, Universit  a del Piemonte Orientale, ``A. Avogadro'' C.so Borsalino, 54 I-15100 Alessandria, Italy Received 6 August 2000; received in revised form 20 December 2000; accepted 5 January 2001 Abstract An active and stable mesoporous titanosilica, denoted as Ti±TUD-1, has been synthesized using a cheap, small and multifunctional chemical, triethanolamine TEA), instead of surfactants. TEA not only is applied as a mesopore template and as a director of positioning Ti-sites onto the internal mesopore surface via the formation of titanium±TEA complexes, but also stabilizes titanium sources, which ensures the possibility of forming isolated tetrahedrally co- ordinated Ti-sites. Ti±TUD-1 features three-dimensionally randomly connected mesopores with walls of about 2:5±4 nm in thickness. Its surface area can reach about 700±1000 m 2 /g and its pore sizes are tunable. After calcination at 1000°C and boiling in water, it kept a high integrity, a high surface area and only a slight change in pore sizes occurred. UV±VIS spectra revealed that tetrahedrally co-ordinated Ti-sites are quite stable under thermal and hydrothermal treatments. It also showed about 5.6 times higher activity for cyclohexene epoxidation than the framework-substituted Ti±MCM-41 and similar activity compared to Ti-grafted MCM-41. Ó 2001 Elsevier Science B.V. All rights reserved. Keywords: Epoxidation; Mesoporosity; Non-surfactant; Template synthesis; Titanosilica 1. Introduction Following the success of microporous titanosi- licate catalysts such as TS-1 [1,2] and TS-2 [3]) in the selective oxidation of small alkanes, alkenes and alcohols, research interest is increasingly turning towards the selective oxidation of large and bulky chemicals, which cannot penetrate into the micropores of zeolites. The discovery of meso- porous materials M41S) [4] with a tunable pore size from 20 to 100  A opened a way to prepare mesoporous titanosilicas, in which tetrahedral Ti can be introduced into the mesopore wall during synthesis, such as in Ti±MCM-41 [5], Ti±HMS [6] and others [7,8], or grafted onto the wall surface of the mesoporous host after synthesis [9]. These mesoporous titanosilicas exhibit high initial cata- lytic activities in the selective oxidations of large alkenes using alkyl hydroperoxide and hydrogen peroxide [6,9]. Recently, an organo-silica contain- ing Ti±MCM-41 has been prepared by Corma et al. [10] introducing methyl groups during synthesis, Microporous and Mesoporous Materials 48 2001) 181±187 www.elsevier.com/locate/micromeso * Corresponding author. E-mail address: z.shan@tnw.tudelft.nl Z. Shan). 1387-1811/01/$ - see front matter Ó 2001 Elsevier Science B.V. All rights reserved. PII:S1387-181101)00342-0