Unique Mesoporous Silicoaluminophosphate Assembled from Faujasite-type SAPO-37 Precursor: A Potential Catalyst for Isomerization

Yadav, Rekha; Singh, Arvind; Sakthivel, Ayyamperumal

doi:10.1246/cl.130446

Cited by 24 publications

(14 citation statements)

References 60 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…To ascertain that the crystalline, faujasitic structure of SAPO‐37 was retained after dual‐templating, the calcined products were analyzed by powder X‐ray diffraction (XRD). To the best of our knowledge, only one group has reported the synthesis of a hierarchical SAPO‐37 material . Although the authors identified mesoporosity by N 2 gas adsorption and low‐angle XRD, the high‐angle XRD pattern of their MESO‐SAPO‐37 was markedly different from FAU, which suggested that the microporous framework was not crystallized.…”

Section: Resultsmentioning

confidence: 99%

Probing the Design Rationale of a High‐Performing Faujasitic Zeotype Engineered to have Hierarchical Porosity and Moderated Acidity

et al. 2020

View full text Add to dashboard Cite

Porosity and acidity are influential properties in the rational design of solid-acid catalysts.P robing the physicochemical characteristics of an acidic zeotype framework at the molecular level can provide valuable insights in understanding intrinsic reaction pathways,f or affording structure-activity relationships.H erein, we employ av ariety of probe-based techniques (including positron annihilation lifetime spectroscopy(PALS), FTIR and solid-state NMR spectroscopy) to demonstrate howahierarchical design strategy for afaujasitic (FAU)z eotype (synthesized for the first time,v ia as ofttemplating approach,w ith high phase-purity) can be used to simultaneously modify the porosity and modulate the acidity for an industrially significant catalytic process (Beckmann rearrangement). Detailed characterization of hierarchically porous (HP) SAPO-37 reveals enhanced mass-transport characteristics and moderated acidity,w hichl eads to superior catalytic performance and increased resistance to deactivation by coking,c ompared to its microporous counterpart, further vindicating the interplay between porosity and moderated acidity.

show abstract

Section: Resultsmentioning

confidence: 99%

Probing the Design Rationale of a High‐Performing Faujasitic Zeotype Engineered to have Hierarchical Porosity and Moderated Acidity

et al. 2020

View full text Add to dashboard Cite

show abstract

“…Figure S2 shows the powder X-ray diffraction patterns of as-prepared diaminosilane functionalized SAPO-37. The diffraction patterns of all the samples (SAPO-37-DAS-0.04 to SAPO-37-DAS-0.32) exhibited characteristic reflections corresponding to the SAPO-37 framework 33 34 35 . The XRD patterns remained intact with a highly crystalline phase even in the presence of large amount of diaminosilane functionality introduced, suggesting that the faujasite-type SAPO-37 framework structure was preserved during synthesis.…”

Section: Resultsmentioning

confidence: 99%

“…This study clearly shows that sodium nitrate extraction method efficiently removes the template from diaminosilane functionalized SAPO-37. The extraction method have been extended to MESO-SAPO-37 (as shown in Figure S6 ) prepared as per the procedure described earlier 34 35 , and other microporous systems viz. SAPO-40, SAPO-5 (as shown in Figure S6 ).…”

Section: Resultsmentioning

confidence: 99%

“…In a typical procedure, SAPO-37 gel was prepared using a molar gel composition of 1.0 (TPA) 2 O: 0.025 (TMA) 2 O: 1.0 Al 2 O 3 : 1.0 P 2 O 5 : 0.43 SiO 2 : 50 H 2 O 33 34 35 . About 5.25 g of pseudoboehmite and 9.17 g H 3 PO 4 were dissolved in distilled water (solution 1) and stirred for 12 h. Then, a solution obtained by adding 1.03 g fumed silica into a mixture containing 40.5 g TPAOH and 0.73 g TMAOH solution was added and stirred for 2 h. The obtained gel was then transferred to a Teflon-lined autoclave and allowed to crystallize for 8 h at 200 °C.…”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

In-situ preparation of functionalized molecular sieve material and a methodology to remove template

Yadav

Ahmed

Singh

et al. 2016

Sci Rep

Self Cite

View full text Add to dashboard Cite

A series of diaminosilane-functionalized silicoaluminophosphate molecular sieve (SAPO-37) was prepared by in-situ synthesis, and a novel method was developed for the selective removal of structure directing agent (SDA)/template from the functionalized SAPO-37.The complete removal of the SDA was evident according to FT-IR, TGA, 13 C MAS-NMR and elemental analysis. The developed method was found to be efficient for removal of template from microporous molecular sieve viz., SAPO-37 and can be applied for other microporous molecular sieves such as SAPO-5, SAPO-40, etc. The powder XRD pattern of the template-removed samples showed a highly crystalline SAPO-37 phase. Argentometric titration revealed that more than 90% of diamine functionality exposed on the surface was accessible for catalytic applications. The resultant materials showed promising activity for ring opening of epoxide with aniline to yield β-amino-alcohol.The synthesis of zeolite and zeolite like microporous molecular sieves with organic functional groups within the channels and framework can tailor their textural as well as catalytic properties depending on the nature of the functional groups incorporated [1][2][3][4][5][6][7][8][9][10][11] . In general, organic functional groups have been introduced on the surface of molecular sieve materials either through in-situ co-condensation using organosilane precursors or by post-synthetic functionalization. The in-situ introduction of organic functional group in inorganic framework, results in organic-inorganic hybrid materials possessing unique properties such as hydrophobic environment, adsorption capacity etc. The hybrid materials are synthesized in hydrothermal conditions and have organic group either as pendent hung within pore or partially substituted either inside the framework or on external surface [12][13][14][15] . The post-synthetic grafting method has been studied extensively for mesoporous materials which are applied in various applications, such as CO 2 capture [16][17][18] and base-catalyzed reactions [19][20][21][22][23][24] . Though mesoporous molecular sieves based materials shown promising applications, their commercial applications are limited owing to poor stability and amorphous wall properties 25 . Although, post-synthetic method covalently anchors functional groups on the surface of molecular sieve materials increasing in surface functionality, it is difficult to control the distribution of functional groups which results in non-homogeneous allocation of functional groups on surface and within the channels 26 . Faujasite (FAU) type microporous molecular sieve possessing 3-D pore structure with pore opening of 12-membered ring and large sodalite cages are commercially important in crude oil industries (about 40% conversions) 27 . Further introduction of organic functionality in microporous molecular sieves will result in new class of shape selective catalysts with organic active group. Three-dimensional framework materials with organic groups were first reported by Maeda et al.1 by in...

show abstract

“…Therefore, its application prospect and future development in modern petrochemical industry are restrained greatly [16], especially for the conversion of large molecules as those encountered in heavy crude oil catalytic cracking process [17,18]. In order to overcome limitations of single microporous or mesoporous molecular sieves and to make preponderance complementarity between the two type molecular sieves, some research groups had extended new synthesis strategy to prepare mesoporous SAPO [19][20][21][22][23][24].…”

Section: Introductionmentioning

confidence: 99%

Catalytic cracking of 1, 3, 5-triisopropylbenzene over silicoaluminophosphate with hierarchical pore structure

Jin

Zhao

et al. 2015

J Porous Mater

View full text Add to dashboard Cite

In order to prepare a highly active catalyst for the catalytic cracking of larger molecules, a novel micromesoporous silicoaluminophosphate composite (define as mesoporous SAPO-5) with hierarchical tri-modal pore size distributions has been firstly synthesized via post-synthetic method in acidic condition and subsequently characterized. Morphology control of the composite is attempted by adjusting pH value of the synthetic system. Three different morphologies of composite, including sphere-, rod-and net-like, are obtained in the different conditions. Possible mechanism for the formation of mesoporous SAPO-5 has been proposed. The mesoporous SAPO-5 exhibits higher cracking activity than conventional microporous SAPO-5 for cracking of 1, 3, 5-triisopropylbenzene (1, 3, 5-TIPB) under the same reaction conditions. The result indicates that the mesoporous SAPO-5 with hierarchical pore structure is favorable for catalytic cracking of large molecule. When the cumene as the reaction molecule, the microporous SAPO-5 catalyst exhibits higher conversion in catalytic cracking of cumene compared to the mesoporous SAPO-5, and the result may be attributed to that microporous SAPO-5 has much stronger acidity and specific selectivity than mesoporous SAPO-5 catalyst in catalytic cracking of cumene. Meanwhile, corresponding carbenium ion mechanism can account for the products formed during the whole reaction process.

show abstract

Unique Mesoporous Silicoaluminophosphate Assembled from Faujasite-type SAPO-37 Precursor: A Potential Catalyst for Isomerization

Cited by 24 publications

References 60 publications

Probing the Design Rationale of a High‐Performing Faujasitic Zeotype Engineered to have Hierarchical Porosity and Moderated Acidity

Probing the Design Rationale of a High‐Performing Faujasitic Zeotype Engineered to have Hierarchical Porosity and Moderated Acidity

In-situ preparation of functionalized molecular sieve material and a methodology to remove template

Catalytic cracking of 1, 3, 5-triisopropylbenzene over silicoaluminophosphate with hierarchical pore structure

Contact Info

Product

Resources

About