Synthesis and catalytic activity of aluminium-free zeolite Ti-β oxidation catalysts

Oxidation of 1,4‐Dioxane over Ti‐MWW in the Presence of H2O2

“…This is in agreement with reported results. [7][8][9] The incorporation of Ti in the framework was further corroborated by IR spectroscopy, with an intense peak around 960 cm À1 observed for all the samples. Note that an additional peak centered at 930 cm À1 was also present in the Ti-MWW sample because this material has several crystallographically inequivalent lattice sites available for Ti 4 + cations.…”

“…[8,9] The liquid-phase oxidation of the various organic substrates with H 2 O 2 (31 % aqueous solution) was conducted with agitation in a 20-mL round-bottomed flask equipped with a condenser. The temperature was controlled by means of a water bath.…”

State of the art of Lewis acid-containing zeolites: lessons from fine chemistry to new biomass transformation processes

“…The efficient fluoride synthetic route followed for the preparation of the hydrophobic Ti-and Sn-Beta zeolites 10,17 has allowed the design of new metallosilicate Beta polymorphs, including isolated zirconium, niobium and tantalum metals as novel Lewis acid sites. 35 Fluoride medium shows a clear advantage against alkaline medium, since the former permits the availability of the metal precursors while in an alkaline medium the metal precursor can be precipitated as the metal oxide, precluding the metal incorporation into the zeolitic framework.…”

Advances in the synthesis of titanosilicates: From the medium pore TS-1 zeolite to highly-accessible ordered materials

“…24 To afford the synthesis of Al-free Ti-Beta zeolite, Corma et al developed a new and reproducible direct synthesis method based on seeding procedures. 25 The authors found that the addition of seeds of Beta in where the Al was eliminated by acid leaching, allowed to grow Al-free Ti-Beta. 25 As could be expected, the selectivity to the epoxide was strongly increased (see Figure 3), being possible to obtain Ti-Beta catalysts with activities much higher than TS-1 for the oxidation of bulkier hydrocarbons.…”

“…25 The authors found that the addition of seeds of Beta in where the Al was eliminated by acid leaching, allowed to grow Al-free Ti-Beta. 25 As could be expected, the selectivity to the epoxide was strongly increased (see Figure 3), being possible to obtain Ti-Beta catalysts with activities much higher than TS-1 for the oxidation of bulkier hydrocarbons. However, the selectivity to desired products, such as epoxides, using Al-free Ti-Beta synthesized in OH media [Ti-Beta(OH)]…”