In Situ Assembly of Nanoparticles into Hierarchical Beta Zeolite with Tailored Simple Organic Molecule

Abstract

A hierarchically structured beta zeolite with intercrystalline mesopores was successfully synthesized via in situ assembly of nanoparticles by employing a simple organic molecule N-p-N, tailored from polyquaternium surfactant, with no hydrophobic long chain. The generated samples were studied by using powder X-ray diffraction (XRD) and nitrogen adsorption/desorption isotherms. Computer simulation, scanning electron microscopy (SEM), and transmission electron microscopy (TEM) technologies were also used. The characterized results show that the tailored template molecule N-p-N without hydrophobic long-chain tail still can direct the zeolite crystallization, while the hydrophobic long-chain tail is not necessary during the mesoporous Beta zeolite formation. The catalytic performances of the sample were studied using alkylation of benzene with propene reaction to evaluate the relationship between the structure and property. The results apparently suggested an overall improved resistance against deactivation as compared to conventional beta zeolite in reactions. Furthermore, this tailored simple organic molecule strategy from dual-functional surfactant for making mesoporous zeolite would offer a new method of synthesizing other hierarchically structured zeolites.

Micro-meso structure NaP zeolite @TiO2 nanocomposite: eco-friendly photocatalyst for simultaneous removal COD and degradation of methylene blue under solar irradiation

“…In addition, it becomes clear that the micropore volume of the zeolite NaP is not affected by the presence of the TiO 2 that means that the TiO 2 particles exclusively reside outside the micropores of the zeolite [36]. The combination of two types of isotherms (I and IV), indicating the presence of both microand mesoporous materials, and the high p/p 0 part suggest that soicroporosityity is also present in the nanocomposite sample [22,37]. Accordingly, the pore size distribution (BJH) of the NaP zeolite@TiO 2 (0.36 g) composite is in the range 2-20 nm with a most frequent pore diameter around of 2.45 nm.…”

Dimethoxymethane Production via Catalytic Hydrogenation of Carbon Monoxide in Methanol Media

“…The micropores nitrogen filling was noticed between 0 < P/P 0 < 0.05 (1st step) while adsorption and desorption of nitrogen in mesopores occurred between 0.4 < P/P 0 < 0.9 (2nd step). 18,19 BJH desorption pores size distribution (inset of Figure 2a) showed no significant difference of mesopores after the impregnation of monometallic and bimetallic catalysts. Moreover, the range of mesopores falls in the region of 3−10 nm because a flat line is observed above 10 nm, and it peaks at 3.8 nm for all the materials.…”

State of the Art and Perspectives of Hierarchical Zeolites: Practical Overview of Synthesis Methods and Use in Catalysis

“…the synthesis proved to be successful since the catalyst showed an improved resistance against deactivation in the alkylation of benzene with propene. [375] In another work, Chaida-Chenni et al investigated two procedures. The first method included a direct hydrothermal method in which an assembly of nanocrystals of preformed beta seeds was formed.…”

“…Despite the fact that this surfactant had no hydrophobic tail, the synthesis proved to be successful since the catalyst showed an improved resistance against deactivation in the alkylation of benzene with propene. [ 375 ]…”