Towards the development of advanced hierarchical chabazite materials: Novel micro-mesoporous silicoaluminophosphate SAPO-34 zeolites

Synthesis of Lamellar Structural Flower-like SAPO-11 Molecular Sieves with Hierarchical Pores for Enhanced Selectivity of Isomeric Alkanes in Hydroisomerization

“…This result showed that the addition of CTAB inhibited the nucleation and growth of the SAPO-11 molecular sieve. It has also been confirmed in the literature that the addition of CTAB as a growth inhibitor has a slightly detrimental effect on the crystal structure. The XRD peaks of SAPO-11-0.2B samples containing KF as a mineralizing agent were sharper and narrower compared to SAPO-11-0.2B-0KF samples without KF (Figure Af).…”

Low‐Temperature NOx Removal Using Cu‐Hierarchical SAPO‐34 Catalysts with High Hydrothermal Stability

“…Regarding the fresh catalysts, they exhibit almost identical profiles compared to those of their zeolite-based supports. [13] Among the Cu-based hierarchical catalysts, "Cu/0.15-fresh" exhibits the highest intensity of the peak at 1.6°, which could be related with a more important long-range order (i. e., higher periodicity) of mesopores. [29,30] As expected, the XRD patterns of the "Cu/microfresh" and "Cu/micro-HT" catalysts did not depict such peak, since these materials are mainly based on small micropores, as it will be underlined below (see Table 2).…”

“…All these fresh catalysts exhibit XRD characteristic peaks of conventional SAPO-34 CHA-based zeolite, with their main peak located at 2θ = 9.5°. [13,26] The crystal size (according to the Scherrer equation) and the relative crystallinity of such catalysts (compared to the crystallinity of the "Cu/micro-fresh" catalyst) are shown in Table 1, as well as the final Cu loading obtained by ICP-OES. Thus, a minor decrease of both, the crystal size and crystallinity, was observed for the Cu-based hierarchical catalysts compared to those of the Cu-based microporous catalyst.…”

“…[10][11][12] The development of hierarchical zeolites with structured and ordered micropores and mesopores could be a promising solution to overcome such issue. In this sense, in our previous study [13] novel hierarchical CHA-based (SAPO-34) materials were developed and optimized by the strategy of soft-templating method (never used before for small-pore zeolites). Both microporous and soft mesoporous templates where introduced at different stages of the synthesis procedure.…”

“…Indeed, two hierarchical zeolite materials were selected on account of their enhanced physico-chemical properties. [13] On the one hand, the material so-called "Aged-Meso-0.15" (with a CTAB/Al molar ratio = 0.15) exhibited a significant volume of mesopores (without a drastic sacrifice of micropores), and the highest long-range order of mesopores among the developed hierarchical materials, together with an important amount of acid sites. On the other hand, the material so-called "Aged-Meso-0.66" (with a CTAB/Al molar ratio = 0.66) also exhibited a similar hierarchical porosity, and even a higher amount of acid sites than the "Aged-Meso-0.15", although the long-range order of mesopores was lower.…”