One way to decrease the global warming is to use bio fuels, preferably second generation, which does not compete with food supply. Therefore is tall oil, an excellent choice of raw material. The tall oil is transesterified to produce fatty methyl esters (FAME), denoted raw tall diesel. However, the use of FAME in the diesel results in e.g. filter clogging. This problem can be solved by hydrogenation of the raw tall diesel to produce n-alkanes that can be used as bio diesel. The objective with this work is to examine the catalyst deactivation in the hydrogenation reaction of methyl laurate, which is used as a model compound for raw tall diesel. Sulphated NiMo will be used as catalyst and it will be characterized thoroughly using XPS, BET, XRD and UV-vis before and after different aging steps. In addition, the activity and selectivity will be detected. Further, isotopic experiments and micro calorimetry are planned. The results will be used to develop kinetic model for the deactivation of the catalyst in the hydrogenation reaction. The goal with the model is to increase the understanding of the deactivation mechanism, determine the rate limiting step and the model could also be used for reactor design. Examples of specific questions: On which sites do different reactions occur and how do they change with aging? How is the binding strength of different components changing after aging? Finally, what is the detailed physical mechanism for the deactivation of the hydrogenation?
Full Professor at Chalmers, Chemistry and Chemical Engineering, Chemical Technology, Chemical Reaction Engineering
Funding Chalmers participation during 2013–2015