Improving the Hydrothermal Stability of Mesoporous Silica SBA-15 by Pre-treatment with (NH4)2SiF6

Song, Mingjuan; Zou, Chenglong; Niu, Guoxing; Zhao, Dongyuan

doi:10.1016/s1872-2067(10)60283-5

Cited by 20 publications

(7 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The SEM images obtained were similar to that of reported by Zhao and co-workers [6], Shahbazi and co-workers [7], and Song and co-workers [22], which had a ropelike morphology that assembled by bundles of ropes. These bundles of ropes were unidirectional and aligned in one direction.…”

Section: Resultssupporting

confidence: 86%

“…This is because there is a broad peak at 3200 to 3500 cm -1 of OH bonds that may have covered these peaks. There is a small peak observed at 2940 cm -1 for sample N and at 2827 cm -1 for sample DN, due to the C-H2 stretching vibration because of methyl groups [22]. Green Technologies for Sustainable & Innovation in Materials 6 and 7 show the SEM images of sample B (silica before calcination) and sample S (silica after calcination) at 5000x magnification.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Preparation and Characterization of Amine-Functionalised SBA-15

Cheah

Thung

Othman

et al. 2013

AMR

View full text Add to dashboard Cite

Ever since the first report of ordered mesoporous silica by the Mobil group, various preparation techniques for mesoporous were extensively studied. In addition to the desirable large surface area, surface of mesoporous silica could be modified for specific catalytic and sensor applications. In this present study, SBA-15 mesoporous silica was prepared and further surface modification was done using organoalkoxysilane (aminopropyl and ethylendiaminopropyl). The resulting bare mesoporous silica, anime-functionalised and diamine-functionalised mesoporous silica were characterized using FTIR, XRD, SEM and EDS for the analysis of incorporation of amine functional groups, phase analysis, powder morphology and elemental analysis.

show abstract

Section: Resultssupporting

confidence: 86%

Section: Resultsmentioning

confidence: 99%

Preparation and Characterization of Amine-Functionalised SBA-15

Cheah

Thung

Othman

et al. 2013

AMR

View full text Add to dashboard Cite

show abstract

“…It is worth noting that the micropore size of modified ZSM‐5 was neither significantly reduced nor increased after the further introduction of K + , and this is probably because of an offsetting effect between re‐created pores and blocked pores. Except for K−Si(0.1 M)‐ZSM‐5, an increase in AHFS concentration followed by the introduction of K + resulted in a slight increase in the micropore and mesopore size of HZSM‐5, and this is probably because some SiO 2 is deposited on the wall and because the introduced K + blocks some channels of HZSM‐5 when the concentration of AHFS is low (0.1 M) …”

Section: Resultsmentioning

confidence: 99%

Selective Adsorption of p‐Cresol from a Mixture of m‐Cresol and p‐Cresol over ZSM‐5 with Controlled Micro‐ and Mesoporosity

Guo

et al. 2019

ChemistrySelect

View full text Add to dashboard Cite

Ammonium hexafluorosilicate (AHFS) 1 at different concentrations was utilized as a mesopore‐generating agent to synthesize hierarchical ZSM‐5 (Si‐ZSM‐5) adsorbents; K+‐exchanged hierarchical ZSM‐5 (K−Si‐ZSM‐5) was successfully prepared by an impregnation method. The properties of adsorbents were characterized using XRD, XRF, N2 adsorption‐desorption and NH3‐TPD. The selectivity separation of p‐cresol 2 and m‐cresol 3 on adsorbents were experimentally investigated using a liquid breakthrough method. The enhanced adsorption capacity of Si‐ZSM‐5 is attributed to the creation of mesopores, which probably led to higher adsorption diffusion. The introduction of K+ into hierarchical ZSM‐5 diminishes the acid sites, strengthens adsorption sites, and reduces the mesopore diameter. Thus, K−Si‐ZSM‐5 possessed higher separation efficiency compared with the parent HZSM‐5. The concentration of AHFS had significant impact on adsorption capacity and the separation efficiency of adsorbents, and AHFS at a concentration of 0.5 M exhibited the optimal adsorption performance. Furthermore, the adsorbent is easy to prepare under laboratory conditions, and through a large scaled‐up breakthrough experiment, it is suitable for practical industrial applications. Also, we propose separation mechanisms of m‐cresol 3 and p‐cresol 2, and these are mainly controlled by shape selection and adsorbent‐adsorbent interactions.

show abstract

“…Figure 5 shows the Py-IR spectra of HZSM-5, Zn/HZSM-5, and Zn-2P/HZSM-5 catalysts evacuated at Meanwhile, new L acid sites (L 1615 ), as confirmed by the Py-IR adsorption peak around 1615 cm −1 , [43,50] are produced. The redistribution of B and L acid sites could be ascribed to the strong interaction between the intrinsic acid sites and the zinc species, and thus partial B acid sites on the HZSM-5 catalyst are converted into Zn-L acid sites.…”

Section: Catalyst Characterizationmentioning

confidence: 92%

“…The increase in crystallinity could be ascribed to the silicon species produced by the hydrolysis of SiF 6 2− , which interacts with the framework of zeolite and repairs partial lattice defects. [42,43] The NH 3 -temperature-programmed desorption profiles of HZSM-5, 0.5P/HZSM-5, 2P/HZSM-5, and Zn-2P/HZSM-5 catalysts are shown in Figure 3. Two typical desorption peaks of the HZSM-5 zeolite, centered at about 270 C (low-temperature peak) and 480 C (hightemperature peak), were observed with all investigated ZSM-5 samples.…”

Section: Catalyst Characterizationmentioning

confidence: 99%

Highly shape‐selective Zn‐P/HZSM‐5 zeolite catalyst for methanol conversion to light aromatics

Jia

Wang

Zhang

et al. 2020

Applied Organom Chemis

View full text Add to dashboard Cite

A highly shape-selective and relatively long-lifetime HZSM-5-based catalyst (Zn-2P/HZSM-5) was prepared by chemical modification with both ZnSiF 6 Á6H 2 O and H 3 PO 4 solution. The phosphoric acid modification could effectively modulate the Brønsted acid strength of the HZSM-5 catalyst, which promotes the oligomerization, alkylation, cyclization, and hydrogen transfer reactions. The introduction of Zn-Lewis acid sites significantly improved the dehydroaromatization of higher olefins. All of these were very beneficial for the generation of BTX (i.e. benzene, toluene, and xylene) hydrocarbons in aromatization of methanol. The coke amount and the average rate of coke formation decreased over the Zn-2P/HZSM-5 catalysts, which may largely be ascribed to its lower strong acid sites and lower outer surface acidity. The catalytic performance of methanol aromatization showed that the Zn-2P/HZSM-5 catalyst exhibited the highest BTX selectivity of about 46.76% and the longest catalytic lifetime of about 498 h at T = 400 C, P = 0.1 MPa, and weight hourly space velocity = 0.7 h −1 .

show abstract

Improving the Hydrothermal Stability of Mesoporous Silica SBA-15 by Pre-treatment with (NH4)2SiF6

Cited by 20 publications

References 30 publications

Preparation and Characterization of Amine-Functionalised SBA-15

Preparation and Characterization of Amine-Functionalised SBA-15

Selective Adsorption of p‐Cresol from a Mixture of m‐Cresol and p‐Cresol over ZSM‐5 with Controlled Micro‐ and Mesoporosity

Highly shape‐selective Zn‐P/HZSM‐5 zeolite catalyst for methanol conversion to light aromatics

Contact Info

Product

Resources

About