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Controlling selectivity and stability of zeolite catalysts for methanol to hydrocarbons and ethylene oligomerization


    Problem Statement

    Olefins are commodity chemicals with applications in the production of plastics (petrochemical industry), lubricants, plasticizers, and surfactants, among many others. However, there is an imbalance between their production and demand, which oligomerization-cracking reactions over zeolites could solve. At the same time, zeolites are excellent catalysts for methanol to hydrocarbons (MTH), olefins (MTO), or aromatics (MTA). The processes aim to produce light hydrocarbons like propylene or convert ethylene into higher-value a-olefins, aromatic hydrocarbons (BTX), and jet fuel.

    Our focus in this project is to modify, synthesize, and develop novel materials of different porosity (engineered at the multiscale): from hierarchical zeolites, nano zeolites, and hollow zeolites to catalytic particles, bodies, spray-dried, and extrudates with tuned properties. Additionally, we incorporate different metals (i.e., Ni, Cr, Zn) to adjust the selectivity of desired products.

    We use various reactors, such as operando or high-throughput packed-bed and batch reactors.

    OLG-O2H

    Goals

    • Control structure–selectivity: Tune zeolite porosity and acidity to maximize propylene and α-olefin yields.
    • Metal modulation: Use Ni, Cr, Zn to bias reaction pathways and improve selectivity to target hydrocarbons.
    • Deactivation control: Reduce coke formation and extend catalyst lifetime with regeneration strategies.
    • Reactor optimization: Shape catalysts into bodies/extrudates and validate 100 h continuous stable operation.

    Related People

    Hend Omar Mohamed
    Kiruthika Jayaseelan

    Related Publications

    Assessment of Thermogravimetric Methods for Calculating Coke Combustion-Regeneration Kinetics of Deactivated Catalyst

    by Ochoa, Ibarra, Bilbao, Arandes, Castaño
    Chem. Eng. Sci. Year: 2017

    Abstract

    This work compares different methodologies for calculating the kinetic parameters of coke combustion, employed for catalyst regeneration, using thermogravimetric methods. A reference fluid catalytic cracking (FCC) spent catalyst was used as a representative example of the deactivated catalyst for the combustion runs, pre-used in the cracking of a vacuum gas oil at 773 K and 3 s. Three different types of approaches have been performed in order to obtain kinetic combustion parameters: (i) kinetic model-based, (ii) isoconversional and (iii) modulated methods. Additionally, a series of empirical modifications have been proposed to predict the kinetic behavior at different heating rates for the model-based approach. Using the best conditions and methods, the combustion activation energy of coke, deposited after the reaction mentioned, is in the order of ∼114, ∼156, and ∼162 kJ mol−1 for the kinetic model-based, isoconversional and modulated methods, respectively. The recommendations for measuring kinetic parameters are reported together with the benefits/disadvantages using the three mentioned approaches.

    Keywords

    O2H OLG CHA FCC REF MKM