Available online at www.sciencedirect.com Materials Chemistry and Physics 107 (2008) 499–504 Liquid phase partial oxidation of olefins over mesoporous titanium silicate molecular sieve synthesized by non-ionic templating route Mahasweta Nandi, Krishanu Sarkar, Asim Bhaumik ∗ Department of Materials Science and Center for Advanced Materials, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032, India Received 10 March 2007; received in revised form 21 August 2007; accepted 25 August 2007 Abstract A highly ordered 2D-hexagonal mesoporous titanium silicate synthesized under moderately basic condition by using a modified synthesis procedure in the presence of a non-ionic surfactant dodecylamine (DDA) as the structure-directing agent (SDA) has been reported. This mesoporous material was characterized by using powder XRD, N 2 adsorption/desorption, TEM, SEM-EDS and spectroscopic studies. UV–vis and 29 Si MAS NMR studies suggested the incorporation of isolated tetrahedral Ti(IV) sites in a highly cross-linked silica framework. N 2 sorption analysis revealed good surface area and narrow pore size distribution. This mesoporous titanium silicate efficiently catalyzed the epoxidation of acrylic acid in acetonitrile solvent in the presence of H 2 O 2 as oxidant with high-yield and excellent selectivity. Oxidation of styrene over this mesoporous titanium silicate has also been studied. © 2007 Elsevier B.V. All rights reserved. Keywords: Microporous materials; Chemical synthesis; Powder diffraction; Adsorption 1. Introduction Mesoporous materials due to their properties such as high specific surface area and uniform pore diameter [1,2] have poten- tial applications in various fields of science, from catalysis to biology [3–7]. Synthesis of mesoporous titanium silicates has attracted wide attention after first reports of selective, eco-friendly and industrially important organic transformations using titanium-containing medium pore zeolite TS-1 and TS- 2, which have shown outstanding catalytic activity in a wide range of oxidation reactions, e.g., oxidations of C–H, N–H, and S–H bonds; epoxidations, hydroxylations, ammoximations, etc. [8–14] in the presence of dilute aqueous H 2 O 2 as oxidant. These catalytic reactions have largely replaced the use of hazardous organic peracids, inorganic acids and other harmful oxidizing agents in various catalytic reactions [10,11] without compro- mising on the selectivity for the desired products. However, their catalytic activities were confined to smaller organic molecules only (C 2 –C 7 ) because of their pore size barrier. The discovery of highly ordered mesoporous silica [1,15] and its titanium silicate ∗ Corresponding author. Tel.: +91 332473 4971x207; fax: +91 332473 2805. E-mail address: msab@mahendra.iacs.res.in (A. Bhaumik). analogue [16], has opened a new window for the synthesis of mesoporous titanium silicates under various reaction conditions by involving supramolecular assembly of different surfactant molecules. The syntheses were carried out employing cationic surfactant, mixture of cationic and anionic surfactant [17] and neutral surfactant molecules [16,18] as templates. Among all the syntheses pathways, the one in which neutral surfactant molecules are used as templates, is very attractive, since hydro- gen bonding is responsible for the cohesiveness between the surfactant molecule and the inorganic precursor. Due to the rel- atively less strong interaction between the entities the extraction of surfactant molecule can easily be achieved by simple sol- vent extraction method, using ethanol for example, instead of calcinations or acid-solvent extraction, which can result in the shrinkage of the pore diameter and consequently collapse of the mesostructures synthesized by ionic surfactant templating routes. Synthesis of titanium silicates using non-ionic surfac- tant, e.g., dodecylamine [16] and 1,12-diaminododecane [18] have been reported. Here we report the synthesis of a meso- porous titanium silicate using dodecylamine (DDA) as template. We have modified the original synthesis procedure reported by Pinnavaia and his group [16]. This modification resulted in a new mesoporous titanium silicate material. The synthe- sis has been carried out under mildly alkaline pH condition 0254-0584/$ – see front matter © 2007 Elsevier B.V. All rights reserved. doi:10.1016/j.matchemphys.2007.08.028