Local environment and catalytic property of External Lewis acid sites in hierarchical lamellar titanium Silicalite-1 zeolites

Hierarchical two-dimensional (2D) lamellar zeolites represent a young emerging field and novel expression of the zeolite frameworks. Accompanied with synthesis catalytic performance investigation, assessment on local environment behavior acid sites in 2D are needed. Here, we described Lewis evaluated activities external (i.e. surface mesopores) titanium silicalite-1 (TS-1) zeolites. For comparison purpose, four TS-1 zeolites, including 3D TS-1, multilamellar without pillarization by silica silica/titania, respectively, were prepared. The Ti-sites, coordination status Ti-atom, speciation hydroxyl (-OH) group that hints degree confinement, site strength accessibility, was collectively assessed spectroscopic organic base titration measurements. Kinetic studies cyclooctene (C8H14) epoxidation hydrogen peroxide (H2O2) discerned activity Ti-sites decreased increasing mesoporosity due to decrease confinement.