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(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Effect of different seed sources on the hydrothermal crystallization of MCM-22 zeolite catalysts

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Rodrigues, Mariana V. [1] ; Vieira, Luiz H. [1] ; Campos, Guilherme P. [1] ; Martins, Leandro [1]
Total Authors: 4
[1] Univ Estadual Paulista, UNESP, Inst Quim, Campus Araraquara, Rua Prof Francisco Degni 55, BR-14800900 Araraquara, SP - Brazil
Total Affiliations: 1
Document type: Journal article
Source: CrystEngComm; v. 20, n. 25, p. 3467-3475, JUL 7 2018.
Web of Science Citations: 1

Zeolites are solid acids with several industrial applications, but usually their syntheses are difficult or costly and this negatively interferes in their use as catalysts or adsorbents. A seed-assisted approach is an alternative route to facilitating zeolite synthesis, shortening crystallization time, allowing template-free synthesis and decreasing costs and is environmentally friendly. In this study, the seed-assisted synthesis was applied to the MCM-22 zeolite. Three types of seeds were studied: the MCM-22, the ball milled MCM-22 and the micro-seeds in the mother liquor from an unseeded synthesis. XRD studies showed successful zeolite crystallization in shorter times, and SEM images pointed out a decrease in the crystal size, with the ball milled seed giving the best results. In the presence of seeds, the organic template was reduced up to 50%, but contamination with zeolite ZSM-5 was detected. The template-free synthesis did not lead to crystallization because in the synthesis of low Si/Al ratio zeolites, the interaction between aluminum and the template is needed for zeolite nucleation, as revealed by carbon and aluminum NMR. Due to the decrease in the crystal size, the seed-synthesized zeolites had an improved catalytic performance in liquid-phase glycerol condensation with acetone. (AU)

FAPESP's process: 14/20116-6 - Development and application of lamellar vanadosilicates as catalysts in the glycerol oxidative dehydration
Grantee:Luiz Henrique Vieira
Support type: Scholarships in Brazil - Doctorate
FAPESP's process: 13/01328-0 - Advanced synthesis methodologies of hierarchical zeolites and characterization by different techniques for improved use of microporous materials in heterogeneous catalysis
Grantee:Leandro Martins
Support type: Regular Research Grants
FAPESP's process: 14/12942-3 - Cooperation between supramolecular chemistry and emulsion in the synthesis of delaminated lamelar catalysts
Grantee:Mariana Veiga Rodrigues
Support type: Scholarships in Brazil - Doctorate