Boron Incorporation by Hydrothermal Synthesis Into SAPO-5 and SAPO-11 Molecular Sieves
نویسندگان
چکیده
Silicoaluminophosphates SAPO-5 and SAPO-11 were synthesized using the hydrothermal method, 170 ºC with triethylamine dipropylamine as structure directing agents, respectively. This work aimed incorporation of boron into structures obtained by modifying composition system, a reaction equation: Al2O3:P2O5:x SiO2: yB2O3:1,5TEA (or DPA):50H2O, x, y=0-0.2. The phase was identified XRD characterized FTIR, TGA/DTG, TPD-NH3 nitrogen adsorption at -196°C. parameters confirmed obtaining pure structures, showing slight contraction in unit cells, indicating presence crystal lattice. Brønsted sites, modified up to maximum (y = 0.1) for higher content, acidity not significant. modification weak related appearance isolated BO3 groups, that silicon atoms sufficiently distributed formation sites.
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ژورنال
عنوان ژورنال: Materials Research-ibero-american Journal of Materials
سال: 2023
ISSN: ['1980-5373', '1516-1439']
DOI: https://doi.org/10.1590/1980-5373-mr-2022-0294