Fatty acid methyl ester biofuels produced from canola oil with honeycomb monolithic catalysts

• Honeycomb monolithic catalysts were formulated with various metal oxides.
• Multi-layers of various metal oxides stabilize and increase catalytic activities.
• Order of loading metal oxides affects stabilities and activities of catalysts.
• Conversion of canola oil to FAMEs increases with decreased reaction temperatures.
• Repeated fluctuation in conversion of canola oil is observed with increased times.

Honeycomb monolithic catalysts were used to convert efficiently vegetable oils to fatty acid methyl esters (FAMEs) as biodiesel fuels. Honeycomb monolithic catalysts were formulated by impregnating honeycomb γ-alumina-wash-coated monolithic catalyst supports with various catalytically active metals such as ZnO, Na2O, MgO, and CaO. Canola oil in methanol was converted to FAME biofuels in a vertical honeycomb monolithic catalysts flow reactor to test catalytic activities and stabilities of formulated catalysts. Initial conversion of canola oil to FAMEs increased with decreased reaction temperatures, but catalytic activities of monolithic catalysts were deactivated severely at 250 °C. Catalysts deactivated at 250 °C can be regenrated by heating them in atmosphere for 4 h at 400 °C. Multi-layers of various active metals impregnated onto honeycomb monolithic catalyst supports stabilize and increase catalytic activities of monolithic catalysts. Order of loading catalytically active metals on honeycomb monolithic catalyst supports affects catalytic activities and stabilities of honeycomb monolithic catalysts. Calcium oxide stabilizes catalytic activities of formulated monolithic catalysts. Conversion of canola oil fluctuates repeatedly with increased reaction times in the honeycomb monolithic catalyst flow reactor.