ChemComm
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DOI: 10.1039/C7CC01126A
COMMUNICATION
ChemComm
HCHO condensed with substantial CH3OH to form DMM. Such
In conclusion, we developed a simple and efficient one-pot
a catalytic system can be used for the reduction of different process for the selective conversion of coconut oil and various
FAMEs, with carbon chains ranging from C12 to C16 and a C12 fatty esters (acids) to fatty alcohols with nearly 100%
fatty acid, producing 83-85% yields in fatty alcohols and 100% selectivity using a highly active and inexpensive Cu/SiO2
selectivity (Fig. 5c). The conversion of coconut oil containing a catalyst in methanol at 240 °C without extraneous H2. The
mixture of fatty acid derivatives, mainly lauric acid, with Cu2O∙SiO2 and Cu0 sites acted synergistically on the surface of
Cu/SiO2-HT, under the optimized reactions conditions using the Cu/SiO2 catalyst prepared by the hydrothermal method
MeOH as the solvent, 240 °C, 2.0 MPa N2, and 4 hours, yielded and catalysed the generation of H2 via methanol
C8-C18 fatty alcohols in a one-pot reaction, with an 83 wt% dehydrogenation. Homolysis of the generated H2 occurred on
yield, at an initial rate of 1.0 goil∙g−1∙h−1, without extraneous H2. the neighboring Cu0 sites, resulting in the formation of H∙
The most abundant product was C12 lauryl alcohol, with a species, which reduced the FAMEs to fatty alcohols. The
43.6% yield (Fig. 5d). In addition, incomplete hydrogenation of developed catalyst combining Cu2O∙SiO2/Cu0 centers had an
FAMEs (formed from transesterification between fatty esters optimal Cu+/Cu0 ratio of 1.76 for the tandem methanol
in coconut oil and methanol) led to these partially reduced dehydrogenation/reduction reaction of fatty esters.
products with a 17% yield. The product distribution (analyzed Additionally, single Cu+ or Cu0 catalysts had no activity for both
by GC-MS, Fig. S15) perfectly mirrored the fatty acid derivative the methanol dehydrogenation and the ester reduction.
composition in the raw coconut oil (Fig. S16).
Hence, this new method resulted in the efficient and selective
reduction of a series of inert fatty acids and esters via a simple
and hydrogen-free process under mild conditions.
We acknowledge the financial support from the National
Key Research and Development Program of China (Grant No.
2016YFB0701100), the Recruitment Program of Global Young
Experts in China, National Natural Science Foundation of China
(Grant No. 21573075).
Notes and references
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Fig. 6 The designed reaction pathway for Cu/SiO2-HT catalyzed selective conversion
of coconut oil to fatty alcohols in methanol. Reaction conditions: coconut oil (0.3 g),
Cu/SiO2-HT (0.2 g), methanol (40 mL), 240 ˚C, 4 h, stirring at 400 rpm.
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