Affiliation:
1. School of Materials Sciences, Indian Association for the Cultivation of Science, 2A & 2B Raja S. C. Mullick Road, Jadavpur, Kolkata 700032, India
2. Light Stock Processing Division, CSIR—Indian Institute of Petroleum, Dehradun 248005, India
Abstract
Selective oxidation of organics over an efficient heterogeneous catalyst under mild liquid phase conditions is a very demanding chemical reaction. Herein, we first report the modification of the surface of mesoporous silica MCM-41 material by phosphate for the efficient incorporation of Ti(IV) in the silica framework to obtain highly ordered 2D hexagonal mesoporous material STP-1. STP-1 has been synthesized by using tetraethyl orthosilicate, triethyl phosphate, and titanium isopropoxide as Si, P, and Ti precursors, respectively, in the presence of cationic surfactant cetyltrimethylammonium bromide (CTAB) under hydrothermal conditions. The observed specific surface area and pore volume of STP-1 were 878 m2g−1 and 0.75 ccg−1, respectively. Mesoporous STP-1 has been thoroughly characterized by XRD, FT-IR, Raman spectroscopy, SEM, and TEM analyses. Titanium incorporation (Ti/Si = 0.006) was confirmed from the EDX analysis. This mesoporous STP-1 was used as a heterogeneous catalyst for the selective oxidation of styrene into benzaldehye in the presence of dilute aqueous H2O2 as an oxidizing agent. Various reaction parameters such as the reaction time, the reaction temperature, and the styrene/H2O2 molar ratio were systematically studied in this article. Under optimized reaction conditions, the selectivity of benzaldehyde could reach up to 93.8% from styrene over STP-1. Further, the importance of both titanium and phosphate in the synthesis of STP-1 for selective styrene oxidation was examined by comparing the catalytic result with only a phosphate-modified mesoporous silica material, and it suggests that both titanium and phosphate synergistically play an important role in the high selectivity of benzaldehyde in the liquid phase oxidation of styrene.
Subject
Organic Chemistry,Inorganic Chemistry,Electrochemistry,Chemistry (miscellaneous)
Reference56 articles.
1. Trost, B.M. (1991). Comprehensive Organic Synthesis, Pergamon.
2. Optimisation of olefin epoxidation catalysts with the application of high-throughput and genetic algorithms assisted by artificial neural networks (softcomputing techniques);Corma;J. Catal.,2005
3. Mechanisms of Epoxide Reactions;Parker;Chem. Rev.,1959
4. Synthesis of an Ultralarge Pore Titanium Silicate Isomorphous to MCM-41 and Its Application as a Catalyst for Selective Oxidation of Hydrocarbons;Corma;J. Chem. Soc. Chem. Commun.,1994
5. Titanium silicate molecular sieve (TS-1)/H2O2 induced triphase catalysis in the oxidation of hydrophobic organic compounds with significant enhancement of activity and para selectivity;Bhaumik;J. Chem. Soc. Chem. Commun.,1995
Cited by
2 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献