because particles of MoO
3
appear to progressively turn dark blue
Materials and Methods
over the course of the reaction. In this regard, 1,2-CS catalysts
that do not readily reduce in the presence of carbohydrates have
the potential to result in higher ultimate lactate yields. Quantifi-
cation of reaction intermediates and by-products under these
relatively mild retro-aldol conditions and their dependence on
Reagents and Catalysts. A full list of chemicals used in this study and their
sources can be found in SI Appendix. The hydrothermal syntheses of Sn-MFI
lished procedures that are described in detail in SI Appendix.
Reaction Analysis. Carbohydrate analysis and fractionation were performed via
HPLC on an Agilent Hi-Plex Ca column with refractive index and evaporative
light scattering detectors. Alkyl lactates were quantified by GC with a flame
ionization detector (FID), and naphthalene as an internal standard. Additional
1,2-CS and 1,2-HS site distribution are some of our current focus.
The use of moderate temperatures (∼100 °C) enables nu-
merous desirable features for the production of lactic acid and
alkyl lactate from hexoses such as lower process pressure and
reduced catalyst deactivation due to product deposition on the
1
13
side products were identified by GC coupled with MS. H and C liquid NMR
spectrometry was used for product identification. Reactions were performed
in thick-walled crimp-sealed glass reactors (VWR) that were heated in a tem-
perature-controlled oil bath. Aliquots were extracted at desired times and
analyzed by HPLC, GC, and/or NMR. Reported yields are on a carbon basis.
Detailed descriptions of procedures followed during reaction testing and
catalysts. The minimal operating pressure for such reactions is
sat
autogenous, and is largely determined by the vapor pressure (P
)
sat
of the solvent. For instance, for methanol, P = 3.5 bar at 100 °C
sat
and P = 21.9 bar at 170 °C (31). We note that, in the case of
Fig. S18, ∼20 h, the MoO /Sn-MFI catalyst combination is still
3
ACKNOWLEDGMENTS. We thank Dr. Mona Shahgholi (Caltech) for use of
GC-MS. This work was financially supported as part of the Catalysis Center
for Energy Innovation, an Energy Frontier Research Center funded by the US
Department of Energy, Office of Science, Office of Basic Energy Sciences
under Award DE-SC0001004. M.O. acknowledges funding from the National
Science Foundation Graduate Research Fellowship Program under Grant
DGE-1144469.
active without regeneration by calcination or washing, as in-
dicated by further production of ethyl lactate upon introduction
of additional fructose to the reaction solution. In our hands, this
is contrary to the coked state of Sn-Beta catalysts that requires
catalyst calcination after high-temperature reactions (3).
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