Sunflower oil to green diesel over Raney-type Ni-catalyst

There are intensive efforts for reforming triglycerides to fuels. A non-pyrophoric Raney nickel type catalyst was investigated in the hydroconversion of sunflower oil. The catalyst was also tested in the transformation of octanoic acid as a model compound at 21 bar in temperature range of 280–340 °C. It was found that alumina supported Ni catalysts (one of them is non-pyrophoric Raney type Ni) selectively catalyze the hydrodecarbonylation and decarboxylation of fatty acids being corrosive intermediates of trigliceride deoxygenation process. Beside the main hydrodecarbonylation reaction Ni-containing catalysts are active in disadvantageous side reactions such as CO methanization and hydrogenolysis of paraffins producing methane byproduct in high concentration with extensive hydrogen consumption. Non-pyrophoric Raney nickel catalyst is more active than Ni/Al 2 O 3 samples especially in the side reactions. To eliminate the active sites responsible for the side reactions the catalyst was modified with tin and lead. It turned out that poisoning either with Sn or Pb did not improve selectivity. Finally addition of In 2 O 3 proved to be effective by directing the transformation to a different deoxygenating reaction pathway resulting in high alcohol yields.