Multilamellar and pillared titanium Silicalite-1 with long-range order of zeolite nanosheet layers: Synthesis and catalysis

Abstract Titanium silicalite-1 (TS-1) nanosheets can be synthesized from the precursor gels containing a diquaternary ammonium template in hydroxide form. The TS-1 nanosheets tend to form unilamellae interconnected in disordered aggregates. Pillaring of TS-1 nanosheets preserves the mesoporosity, but lacks long-range order of nanosheet layers. Here, we report synthesis of multilamellar TS-1 (M-TS-1) with long-range order of nanosheet layers from the precursor gels containing hexanediamine (C 6 DN) and diquaternary ammonium template in bromide form (C 22-6-6 Br 2 ). Pillaring of M-TS-1 produced pillared TS-1 (P-TS-1) with well-preserved mesoporosity and long-range order of layers. The influences of concentrations of C 22-6-6 Br 2 , C 6 DN, and Ti precursor as well as crystallization time, on the resultant M-TS-1 were investigated. The physicochemical properties of the M-TS-1 and P-TS-1 were studied and compared to the conventional TS-1 zeolite. The presence of mesopores in P-TS-1 enhanced the catalytic performance in reactions involving bulky molecules.