Synthesis and Pore Structure of Mesozeolite FAU

doi:10.15541/jim20140135

Abstract

Abstract:

Mesoporous zeolites X and Y with FAU structure were hydrothermally synthesized using an organos-ilane surfactant (TPOAC) as mesopore-generating agent, which was added into the conventional synthesis system of the crystalline microporous aluminosilicates. X-ray diffraction, scanning electron microscope, high-resolution transmission electron microscope, N₂ adsorption-desorption isotherms and thermogravimetric analysis were used to characterize their structural and textural features. The results showed that the presence of TPOAC led to nanoscale zeolite crystals and abundant intracrystal mesopores at diameter of 5~6 nm, forming the meso-zeolites X and Y with micropores, intra- and inter-mesopores. Both mesoporous zeolite X and Y displayed not only inherent topological and microporous structure of zeolite FAU, but also different morphology from conventional zeolite FAU crystals.

Key words: zeolite FAU, hierarchical zeolite, mesoporous templates

CLC Number:

TQ174

FENG Chun-Feng, MA Li, MA Jing-Hong, LI Rui-Feng. Synthesis and Pore Structure of Mesozeolite FAU[J]. Journal of Inorganic Materials, 2014, 29(11): 1173-1178.

Figures/Tables 7

Fig. 1 XRD patterns of NaX, MNaX (a) and NaY, MNaY (b)

Fig. 2 SEM images of NaX (a) and MNaX (b)

Fig. 3 SEM images of NaY (a) and MNaY (b)

Fig. 4 HRTEM images of MNaX (a) and MNaY (b) zeolites

Fig. 5 N2 adsorption-desorption isotherms NaX and MNaX(a); NaY and MNaY (b) and relative DFT pore size distribution (c, MNaX; d, MNaY) of zeolites with FAU structure, respectively

Table 1 Pore structure parameters of zeolites with FAU structure

Sample	S_BET/(m²·g^-1)	S_ext/(m²·g^-1)	S_mic/(m²·g^-1)	V_mic/(cm³·g^-1)	V_meso/(cm³·g^-1)	d_p/nm
NaX	943	26	917	0.35	0.04	-
MNaX	872	141	731	0.27	0.21	5.9
NaY	945	28	917	0.35	0.06	-
MNaY	971	177	794	0.29	0.19	5.5

Fig. 6 TG curves of NaX, MNaX (a) and NaY, MNaY (b)

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