Hierarchical Porous Honeycomb Nico/C Catalyst for Decarboxylation of Fatty Acids and Upgradation of Sewage Sludge Crude Oil

Abstract

Honeycomb NiCo/C-Na catalyst featured with a micro-meso-macropore structure is fabricated and shows a significantly higher catalytic activity for decarboxylation of fatty acid compared to a series of other carbon-based catalysts. A 100% conversion of stearic acid and a C15-18 alkane total yield of 70% is achieved at 280oC for 3h under 1 MPa H2 with heptadecane as the main product. NiCo/C-Na also achieves a complete conversion of monoglyceride into heptadecane when using edible oil as the reactant. Moreover, the catalyst is further evaluated for upgradation of sewage sludge crude oil and proves to be highly efficient. The obtained upgraded oil exhibits a decrease in viscosity and an increase in density. Specifically, the Higher Heating Value (HHV) increases to 47.32 MJ/kg. This result is attributed to the easier desorption of CO2, better H2 activation capacity and the unique hierarchical pore structure of the catalyst, which allows faster mass transfer and reaction rate.

Keywords: fatty acids, decarboxylation, C-C bond cleavage, Biodiesel, Nickel