Template synthesis, structure, sorption properties and acidity of micro-mesoporous materials obtained from sol-precursor of zeolite BEA

摘要

Partially zeolitized micro-mesoporous materials (the total specific surface area S_(BET)= 460-645 m~2/g, mesopore volume V_(meso) = 0.30-0.57 cm~3/g, mesopore diameter D_(meso) ≈ 5.6 nm, micropore volume V_(micro) = 0.11-0.16 cm~3/g, micropore diameter D_(micro) ≈ 0.72 nm) and X-ray amorphous micro-mesoporous materials with uniform mesoporous structure (mesopore specific surface area S_(meso) = 820-890 m~2/g, total pore volume V_t = 0.71-0.86 cm~3/g, V_(meso) = 0.53-0.67 cm~3/g, D_(meso) = 1.8-2.4 nm) were obtained by micellar templating of sol-precursor containing primary products of crystallization of zeolite BEA under conditions typical for forming of mesoporous molecular sieve MCM-41 (hydrothermal treatment at 100-130 ℃ for 3-5 days). It was found that the obtained X-ray amorphous micro-mesoporous materials contain secondary building units of zeolite BEA (five-membered rings of Si-O tetrahedra of BEA) and show acidic properties comparable to zeolite BEA.