Synthesis of silicalite tubular membranes by in situ crystallization

Zeolite Membranes in Catalysis—From Separate Units to Particle Coatings

“…On the one hand, one-step techniques referred to as direct in situ crystallization are applied. Thereby, the surface of the untreated either tubular or disc support is brought in a direct contact with an aluminosilicate precursor solution and the membrane crystallization is performed under hydrothermal conditions as shown exemplarily in the following references [49][50][51][52][53][54][55]. Alternatively, Caro et al proposed a seeding-free synthesis strategy for the preparation of dense and phase-pure zeolite LTA and FAU membranes using 3-aminopropyltriethoxysilane (APTES) as covalent linker between the zeolite layer and the alumina support [56,57].…”

Pervaporation of Ethanol/Water Mixtures Through a High-Silica MFI Membrane: Comparison of Different Semi-Empirical Mass Transfer Models

“…The advantage of silicalite-1 membranes in the separation of ethanol from aqueous solutions is attributed to the hydrophobic properties and well-defined pore size of silicalite crystals [16]. Ethanol-water separation factors of up to 106 [17] have been reported in pervaporation through MFI membranes, with the typical value being around 40 [2]. The typical value for total flux is around 1 kg m -2 h -1 .…”

“…Zeolite membranes are typically synthesized on porous inorganic supports, which are needed to supply the mechanical strength to the thin membranes. The MFI membranes prepared are typically tens of micrometers [16,17,[19][20][21] or several hundreds of micrometers thick [22][23][24]. However, as thin as ca.…”

Ethanol perm‐selective B‐ZSM‐5 zeolite membranes from dilute solutions

“…The results suggest that faster crystal growth rate could effectively close pores among the grain crystals at higher temperature and the obtained membranes would become thicker than that at lower temperature, which would reduce the permeation flux. 27,42 Therefore, M3 displayed the best PV performance and synthesis temperature of 448 K was chosen for preparation of high-quality B-ZSM-5 membranes in the following work.…”

“…The poor compactness and several holes were clearly observed on the M15 surface, probably due to the nonuniform sized zeolite grains. 27,42,43 When the H 2 O/SiO 2 ratios were in the range of 200-600, the support surface was completely covered with well-intergrown zeolite crystals with triangular pitched roofs. These crystals were typically oriented with their c axis normal to the support as depicted by the XRD results (Figures 3 and 8).…”