ACS Catalysis
Letter
Figure S3 may explain the lower heptadecane yields observed
for the ZIF-8 composed samples.
ASSOCIATED CONTENT
* Supporting Information
The Supporting Information is available free of charge on the
■
S
In our studies, zeolite 5A beads acted as acid36,45 catalytic
support, providing a large surface area, and playing an
important role on the dispersion of Pt. Our group32,34 and
independent groups46,47 have observed that acidic supports
promote a better (higher) dispersion of the noble metal and
therefore result in improved catalytic activity for decarbox-
ylation and dehydroxygenation reactions. STEM revealed that a
better Pt dispersion was achieved when Pt was deposited on
zeolite 5A as compared to neutral carbon pellets. In the case of
neutral carbon pellets, a broader Pt nanoparticle size
distribution and clustering was observed (Figure S4).
Detailed catalyst synthesis, catalyst characterization,
reaction procedures, and product analysis methods;
digital pictures of representative catalysts, decarboxyla-
tion % results, N2 BET surface areas, product distribution
of Pt-ZIF-8 membrane-zeolite 5A catalyst (PDF)
AUTHOR INFORMATION
Corresponding Author
Notes
■
It is important to mention that the reduction of Pt content
(leaching) and the reduction in surface area of the Pt/zeolite
5A and Pt/ZIF-67/zeolite 5A catalysts after recycling correlated
to the decrease in heptadecane yield. More specifically, the
higher the reduction on Pt content and surface area, the lower
the heptadecane yield.
Another important observation was that the yield of
octadecane increased in the following order: second recycled
> first recycled > fresh. Interestingly, the C/Pt ratio correlated
with the octadecane yield. More specifically, the yield of
octadecane increased when the C/Pt ratio increased (Figure S5
species can have a positive effect for hydrotreating processes48
including oxygen removal (which is the case in the conversion
of oleic acid to octadecane). It has been hypothesized that a
geometrical effect by which carbonaceous species may isolate
the catalytic active species and stabilize them against sintering.47
Another possibility is that these carbonaceous species may
reduce the interaction of the catalytic active phase and the
support, resulting in an enhanced activity.49
The authors declare no competing financial interest.
ACKNOWLEDGMENTS
■
M.A.C. thanks the Coors foundation for financial support of
this work. J.B.J. acknowledges support from National Science
Foundation EPSCoR program (award no. 1355438). We thank
Xuhui Feng for helping with XRD.
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