In this work the hydrogenation of dibenzyl toluene as a liquid organic hydrogen carrier was studied. Dibenzyl toluene is used as a heat-transfer substance; it has similar properties to fossil fuels, it is not toxic, it is liquid in the appropriate temperature range, has low vapour pressure, and the hydrogenated form has high hydrogen content. It has already shown good results with the use of a noble metal catalyst, this work studied also the use of cheaper catalysts based on nickel. A micro-kinetic model for a commercial 5% Ni/Al$_2$O$_3$ catalyst was developed and kinetic parameters were obtained for the given reactions (given in the table below are the kinetic parameters for the reactions of aromatic ring hydrogenation for the compounds dibenzyl benzene, dibenzyl toluene and dibeznyl ethyl benzene). Recycle tests for the catalyst activity were also performed and lab-made catalysts were also synthesized and tested. Catalysts based on nickel show good potential for dibenzyl toluene hydrogenation, though for widespread use they would need to be modified and improved further.
|