Titanium silicalites size limitations

A newer technology based on metal-peroxo chemistry, without most of the drawbacks just outlined, and usable in the above cases, employs the titanium silicalite (TS-1) heterogeneous catalyst. This works with aqueous hydrogen peroxide, with methanol as a co-solvent if required by the substrate, under relatively mild conditions. The epoxidation of a range of olefins has been demonstrated [72] some are oxidised to other products, such as styrene to phenylacetaldehyde. The system is powerful enough to oxidise terminal olefins and, e.g., allyl chloride. Its main limitation is upon the size of the substrate and products, which must pass down zeolite channels 5.5 A in diameter. 

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