An alternative route to the conventional one for fatty alcohol synthesis was investigated. It was possible to synthesize lauryl alcohol from methyl laurate via reduction by transfer of hydrogen and hydride in liquid phase, in noncatalytic reactions and without the supply of H2 gaseous. Pure NaBH4 or alumina‐supported NaBH4 and methanol were used as co‐reactants and 100% fatty alcohol selectivities were achieved. The aim of supporting the metal hydride was to increase its stability and achieve the full recovery of the solid at the end of reaction. When alumina‐supported NaBH4 was used, a final fatty alcohol yield of 93% was achieved. The use of methanol and NaBH4 in amounts higher than stoichiometric is important to generate alkoxyborohydride anions which act as better reducing species than NaBH4. The reaction conditions effect was investigated and the role of short carbon chain alcohol structure was elucidated. The effect of fatty acid methyl ester structure was also studied. Fatty acid methyl esters with shorter carbon chain length and without unsaturation (methyl laurate, methyl myristate) were easily reduced using NaBH4/Al2O3 and methanol reaching high conversions and fatty alcohol selectivities. Unsaturated fatty acid methyl ester with longer carbon chain (methyl oleate) introduced steric hindrance which disfavoured interaction between ester and reducing solid surface and fatty acid methyl ester conversion was noticeably lower. A reaction mechanism based on alkoxyborohydride anions as the actual reducing species was proposed. This mechanism fully interprets results obtained during fatty acid methyl ester reduction using short carbon chain alcohols and metal hydride.

The formation, stability, and reactivity of the species generated by the reduction reaction of solid NaBH4 with methanol in the liquid phase were investigated by experimental FTIR studies and Density...

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The upgrading of oleyl alcohol synthesis via methyl oleate reduction using NaBH 4 without H 2 supply was investigated. It was possible to synthesize selectively oleyl alcohol with high yields. Non-catalytic and catalytic experiments were developed trying to improve the low final oleyl alcohol yield previously obtained. The effect of reaction temperature, methyl oleate/NaBH 4 molar ratio and properties of different catalysts on final oleyl alcohol yield were analyzed. Thus, alumina-supported metal (M) catalysts (M = Fe, Ce, Mo) were synthesized by incipient wetness impregnation. The M/Al 2 O 3 catalysts were characterized in their chemical, textural, structural and acid-base properties using ICP, N 2 physisorption, XRD and temperature-programmed desorption (TPD) of NH 3 and CO 2 . During non-catalytic methyl oleate reduction, final methyl oleate conversion and oleyl alcohol yield of 94% were obtained using a methyl oleate/ NaBH 4 molar ratio of 0.11 at 333 K. Catalytic activity of M/Al 2 O 3 solids increases as acid site number and ionic potential of M cations increase. In addition, the reaction mechanism for fatty acid methyl ester reduction was investigated from a theoretical approach using Density Functional Theory method at B3LYP/6-31++G(d,p) computational level. Results obtained during theoretical calculations confirmed that the formation of reducing alcoxyborohydride species is energetically favored and allowed to understand the events at microscopic level involved in the reaction mechanism.

The upgrading of oleyl alcohol synthesis via methyl oleate reduction using NaBH4 without H2 supply was investigated. It was possible to synthesize selectively the valuable unsaturated fatty alcohol with high yields. Non-catalytic and catalytic experiments were developed trying to improve the low final oleyl alcohol yield previously obtained. The effect of reaction temperature, methyl oleate/NaBH4 molar ratio and properties of different catalysts on final oleyl alcohol yield was analyzed. Thus, alumina-supported metal (M) catalysts (M = Fe, Ce, Mo) were synthesized by impregnation at incipient wetness. The M/Al2O3 catalysts were characterized in their chemical, textural, structural and acid-base properties using ICP, N2 physisorption, XRD and NH3 and CO2 TPD. During non-catalytic methyl oleate reduction final methyl oleate conversion and oleyl alcohol yield of 94% were obtained using a methyl oleate/NaBH4 molar ratio of 0.11 at 333 K. Catalytic activity of M/Al2O3 solids did not correlate with basic site number but increased as acid site number and ionic potential of M cations increase. This suggests that cations with high acid site number and polarizing power are the ones that promote the polarization of the ester C=O and anion [BH4]- bonds favoring de methyl oleate conversion. In addition, the reaction mechanism for fatty acid methyl ester reduction was investigated from a theoretical approach using Density Functional Theory method at B3LYP/6-31++G(d,p) computational level. Results obtained during theoretical calculations confirmed that the formation of reducing alcoxyborohydride species is energetically favored and allowed to understand the events at microscopic level involved in the reaction mechanism.