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Direct deoxygenation of long‐chain fatty acids can produce both saturated alkanes (CnH2n+2) and unsaturated olefins (CnH2n). However, the selectivity for the production of olefins via the decarbonylation route is relatively low because of the more favorable decarboxylation pathway. We present an atomically ordered intermetallic PtZn alloy on carbon catalyst (PtZn/C) with a record‐high total selectivity (97 %) for undecane (C11H24) and undecene (C11H22) in the deoxygenation of lauric acid (C12H24O2). Interestingly, the selectivity for C11H22 is as high as 67.0 % on PtZn/C, which is significantly higher than that of 27.5 % obtained on the Pt/C counterpart under the same reaction conditions. Characterization and theoretical calculation results reveal that the intermetallic PtZn alloy not only inhibits the decarboxylation route by increasing the energy barrier of −COO* cleavage, but also facilitates the decarbonylation route by decreasing CO desorption energy, and therefore the major product is switched from alkanes to olefins.

Ni/AC (nickel on active carbon) catalysts with different Ni loadings were synthesized and studied for the decarboxylation and aromatization of oleic acid in the absence of H 2 or hydrogen donors. Without the use of hydrogen source, the whole deoxygenation process became more economical. Moreover, oleic acid can be saturated using the H 2 derived from the production of aromatics, which were also considered as the critical component in aviation biofuels. The structure and properties of the catalysts were investigated using X-ray diffraction, transmission electron microscopy, and temperature-programmed desorption of CH 3 COOH and CO. The experimental and characterization results revealed that 30% Ni/AC had a higher adsorption capacity of CH 3 COOH among the other Ni/AC catalysts and highly dispersed and small Ni particles, providing a heptadecane yield of 40.7%. It also contained 13.8% aromatics, which fulfills the requirement of aviation fuels. This Ni/AC catalyst showed good stability even after being reused thrice.

Highly efficient production of hydrocarbons from the decarbonylation of stearic acid in the absence of H2 over Ni/AC.