Model-driven catalyst design for ethanol dehydration into ethylene

November 24, 2022

Olefins, mainly produced by steam cracking, are playing a bigger part in the chemical industry, year by year. However, with the rise in environmental awareness and the new environmental policies, the search for greener production processes is very important. Dehydration of ethanol into ethylene, the process of interest in this thesis appears as one of the main alternatives to this problem. However, the ideal catalyst for this is yet to be found. Hence, a methodology previously developed, named ”Model-driven catalyst design”, was applied in this work to identify the most suitable catalyst properties to maximize ethylene yield. This methodology integrates the kinetics of the process, by using identified catalyst descriptors, namely chemisorption enthalpies, sticking coefficients and active site density, with statistical tools. It has as main objective to establish relationships between catalyst properties and the observed performance. Experimental data reported in two different studies obtained over zeolite-based catalysts modified through dealumination and metal doping processes, with phosphorous and lanthanum, were used in this work to correlate catalyst physical properties with their catalytic activity. Obtained relationships show that lower chemisorption enthalpies of ethylene are associated with good performances while higher values are related to worst performance selectivity-wise. This appeared associated with catalysts doped with phosphorous, which leads to modifications in the catalyst’s porous structure and in the acidity of the catalyst. Yet, this constitutes preliminary conclusions and broader datasets should be studied in the future, so getting to an optimal catalyst composition can be an easier process.

Authors in the community:

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  D

  Diogo Rafael Teixeira de Ascensão

  ist190448

Supervisors of this institution:

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  C

  Carla Isabel Costa Pinheiro

  ist12547

chemical-engineering - Chemical engineering

por - Portuguese

Instituto Superior Técnico