Table 1 Physical properties of H-FAU3.5 and H-FAU2.8 zeolites

From: Machine learning-assisted crystal engineering of a zeolite

Zeolitea

Si/Al ratiob

Na/Al ratiob

(Si/Al)F, Na-FAU ratioc

(Si/Al)F, H-FAU ratioc

Chemical formula per zeolite unit celld

Proton density (μmol/g)e

HSOD/HSUP (infrared)f

HSOD (μmol/g)g

HSUP (μmol/g)g

H-FAU2.8

2.8

0.32

2.73

2.79

(Al2O3)0.6(Na16·65H2O)H34.4Al51Si141O384

2630

3.03

1977

653

H-FAU3.5

3.5

0.50

3.48

3.63

(Al2O3)0.9(Na21·83H2O)H20.7Al41Si151O384

1529

3.24

1168

361

  1. a2.8 and 3.5 were measure from ICP analysis for corresponding Na-FAU zeolites. Na-FAU3.5 was prepared from entry 91 of Supplementary Table 1, and Na-FAU2.8 was prepared from entry 24 of Supplementary Table 1.
  2. bFrom ICP analysis for H-FAU zeolites.
  3. cEstimated from 29Si-NMR spectra for Na-FAU and H-FAU zeolites respectively in accordance with “Loewenstein’s rule” (see Section S5 in SI, Supplementary Table 27)58.
  4. dCalculated via a combination of framework Si/Al ratio for Na-FAU (column 4), Na/Al ratio for H-FAU (column 3), and framework Si/Al ratio for H-FAU (column 5), considering that the total number of T atoms per unit cell is 192 and each Na+ cation is coordinated with four water molecules65,66. Extra-framework aluminum content is approximated as Al2O3 and is provided along with the zeolite unit cell formula. All numbers that appear in chemical formulae are rounded to the nearest integer, except H and Al2O3 components.
  5. eCalculated by dividing the specific H+ number per unit cell by the molecular weight using chemical formulae (column 6).
  6. fCalculated from the equation of HSOD/HSUP = (OH3550/ε3550)/(OH3640/ε3640) based on the Lambert-Beer law, and the infrared spectra of dehydrated H-FAU zeolites are shown in Fig. 5(g). Here, extinction coefficients ε(OH)3640 = 6.76 cm/μmol, and ε(OH)3550 = 5.39 cm/μmol59,67.
  7. gCalculated from the equations of HSOD = HSOD/(HSOD + HSUP) × proton density and HSUP = HSUP/(HSOD + HSUP) × proton density, where proton densities and HSOD/HSUP values are provided in columns 7 and 8, respectively.
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