Titanium-containing mesoporous molecular sieves for catalytic oxidation of aromatic compounds

• Published in: Nature (London) 1994-03, Vol.368 (6469), p.321-323
• Main Authors: Tanev, Peter T, Chibwe, Malama, Pinnavaia, Thomas J
• Format: Article
• Language: English
• Subjects: Alkenes; Amines - chemistry; Aromatic compounds; Benzene; Catalysis; Catalysts: preparations and properties; Chemistry; Crystallography, X-Ray; Exact sciences and technology; General and physical chemistry; Humanities and Social Sciences; Hydrocarbons - chemistry; Hydrogen peroxide; letter; Materials science; multidisciplinary; Organic compounds; Oxidation; Oxidation-Reduction; Phenols; Pore size; Science; Science (multidisciplinary); Silica; Silicon Dioxide - chemistry; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; Titanium; Titanium - chemistry
• ISSN: 0028-0836; 1476-4687
• DOI: 10.1038/368321a0

TITANIUM silicalite is an effective molecular-sieve catalyst for the selective oxidation of alkanes, the hydroxylation of phenol and the epoxidation of alkenes in the presence of H 2 O 2 (refs 1–3). The range of organic compounds that can be oxidized is greatly limited, however, by the relatively small pore size (about 0.6 nm) of the host framework 4 . Large-pore (mesoporous) silica-based molecular sieves have been prepared recently by Kresge et al l 5–7 and Kuroda et al 8 .; the former used a templating approach in which the formation of an inorganic mesoporous structure is assisted by self-organization of surfactants, and the latter involved topochemical rearrangement of a layered silica precursor. Here we describe the use of the templating approach to synthesize mesoporous silica-based molecular sieves partly substituted with titanium—large-pore analogues of titanium silicalite. We find that these materials show selective catalytic activity towards the oxidation of 2,6-ditert-butyl phenol to the corresponding quinone and the conversion of benzene to phenol.