The societal significance of catalysis and the growing practical importance of single-site...
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The societal significance of catalysis and the growing practical importance of single-site heterogeneous catalysts by John Meurig Thomas Proceedings A Volume 468(2143):1884-1903 July 8, 2012 ©2012 by The Royal Society
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Transcript of The societal significance of catalysis and the growing practical importance of single-site...
The societal significance of catalysis and the growing practical importance of single-site heterogeneous
catalysts
by John Meurig Thomas
Proceedings AVolume 468(2143):1884-1903
July 8, 2012
©2012 by The Royal Society
An archetypal single-site heterogeneous catalyst (SSHC), (a) high-resolution electron micrograph of H-ZSM-5, and a Brønsted acid catalyst, empirical formula Hm+Sin−m Alm O2n
where the Si/Al ratio (n–m)/m is ca 25/1.
John Meurig Thomas Proc. R. Soc. A 2012;468:1884-1903
©2012 by The Royal Society
A single-site, multinuclear nanocluster, Ru10Pt2C2 (bound to a mesoporous silica surface, right) catalyses the hydrogenation of muconic acid (derived from biological sources) into adipic acid,
which is one of the building blocks of nylon 6,6.
John Meurig Thomas Proc. R. Soc. A 2012;468:1884-1903
©2012 by The Royal Society
Computed energy levels of outermost electrons in a nanocluster Pt3 compared with the corresponding computed levels in a much larger cluster Pt309.
John Meurig Thomas Proc. R. Soc. A 2012;468:1884-1903
©2012 by The Royal Society
High-resolution electron micrograph of silicalite SiO2, which has the same framework structure as that of ZSM-5.
John Meurig Thomas Proc. R. Soc. A 2012;468:1884-1903
©2012 by The Royal Society
The catalytic cycle, including density functional theory calculated energies, for the epoxidation of an alkene R CH=CH2 to its epoxide by a four-coordinated TiIV active site at a mesoporous
silica surface.
John Meurig Thomas Proc. R. Soc. A 2012;468:1884-1903
©2012 by The Royal Society
In situ X-ray absorption fine structure spectroscopy (XAFS), shown at the extreme left, coupled with in situ FTIR (not shown), can trace the conversion of the precursor organometallic
titanocene dichloride (whose entry into a single mesopore of the silica i...
John Meurig Thomas Proc. R. Soc. A 2012;468:1884-1903
©2012 by The Royal Society
All three of these microporous SSHC, composed of framework-substituted aluminium phosphates, exhibit high Brønsted acid catalytic activity in the dehydration of ethanol and
methanol to produce ethylene and other light olefins.
John Meurig Thomas Proc. R. Soc. A 2012;468:1884-1903
©2012 by The Royal Society
An outline of the mechanistic details involved in the use of a trifunctional SSHC for the production of propylene from ethylene.
John Meurig Thomas Proc. R. Soc. A 2012;468:1884-1903
©2012 by The Royal Society
A summary of sequence of conversions that produce ε-caprolactam (and its linear polymer, nylon 6) from cyclohexanone (1) via its oxime (2).
John Meurig Thomas Proc. R. Soc. A 2012;468:1884-1903
©2012 by The Royal Society
Illustration of the supremacy of the bifunctional nanoporous catalyst, composed of CoIII (redox) and MgII (Brønsted) active centres for the solvent-free production of caprolactam and nylon 6
without generating unwanted solid products.
John Meurig Thomas Proc. R. Soc. A 2012;468:1884-1903
©2012 by The Royal Society
