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Fluid catalytic cracking: recent developments on the grand old lady of zeolite catalysis.

Vogt ET, Weckhuysen BM - Chem Soc Rev (2015)

Bottom Line: These trends include ways to make it possible to process either very heavy or very light crude oil fractions as well as to co-process biomass-based oxygenates with regular crude oil fractions, and convert these more complex feedstocks in an increasing amount of propylene and diesel-range fuels.In addition, we present an overview of the state-of-the-art micro-spectroscopy methods for characterizing FCC catalysts at the single particle level.These new characterization tools are able to explain the influence of the harsh FCC processing conditions (e.g. steam) and the presence of various metal poisons (e.g. V, Fe and Ni) in the crude oil feedstocks on the 3-D structure and accessibility of FCC catalyst materials.

View Article: PubMed Central - PubMed

Affiliation: Inorganic Chemistry and Catalysis Group, Debye Institute for Nanomaterials Science, Faculty of Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands. e.t.c.vogt@uu.nl b.m.weckhuysen@uu.nl.

ABSTRACT
Fluid catalytic cracking (FCC) is one of the major conversion technologies in the oil refinery industry. FCC currently produces the majority of the world's gasoline, as well as an important fraction of propylene for the polymer industry. In this critical review, we give an overview of the latest trends in this field of research. These trends include ways to make it possible to process either very heavy or very light crude oil fractions as well as to co-process biomass-based oxygenates with regular crude oil fractions, and convert these more complex feedstocks in an increasing amount of propylene and diesel-range fuels. After providing some general background of the FCC process, including a short history as well as details on the process, reactor design, chemical reactions involved and catalyst material, we will discuss several trends in FCC catalysis research by focusing on ways to improve the zeolite structure stability, propylene selectivity and the overall catalyst accessibility by (a) the addition of rare earth elements and phosphorus, (b) constructing hierarchical pores systems and (c) the introduction of new zeolite structures. In addition, we present an overview of the state-of-the-art micro-spectroscopy methods for characterizing FCC catalysts at the single particle level. These new characterization tools are able to explain the influence of the harsh FCC processing conditions (e.g. steam) and the presence of various metal poisons (e.g. V, Fe and Ni) in the crude oil feedstocks on the 3-D structure and accessibility of FCC catalyst materials.

No MeSH data available.


Confocal fluorescence microscopy images showing the visualization of zeolite Y aggregate domains within an FCC catalyst particle with (a and b) and without (c and d) zeolite material. The images were obtained after reaction with thiophene (green) at 373 K and subsequent staining with Nile Blue (red) at 298 K. Images b and d are magnified views of the highlighted areas in a and c, respectively. (Reproduced with permission from ref. 175, Copyright Macmillan Publishers, 2011).
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fig27: Confocal fluorescence microscopy images showing the visualization of zeolite Y aggregate domains within an FCC catalyst particle with (a and b) and without (c and d) zeolite material. The images were obtained after reaction with thiophene (green) at 373 K and subsequent staining with Nile Blue (red) at 298 K. Images b and d are magnified views of the highlighted areas in a and c, respectively. (Reproduced with permission from ref. 175, Copyright Macmillan Publishers, 2011).

Mentions: Buurmans, Ruiz-Martinez and coworkers175 have developed a set of selective staining reactions, which are catalyzed by Brønsted acid sites, making it possible to localize zeolite aggregate domains with a confocal fluorescence microscope. More specifically, various thiophene and styrene derivatives could be oligomerized selectively within the pores of zeolites Y and ZSM-5 embedded in an FCC catalyst matrix. As the resulting probe molecule oligomers have a distinct optical spectrum in the visible region of the spectrum, it was possible to excite the oligomers formed with an appropriate laser excitation in a confocal fluorescence microscope with a 2D spatial resolution of 500 nm. This selective staining approach is illustrated in Fig. 27 for two fresh FCC catalyst particles, one containing zeolite Y, whereas the other one was devoid in zeolite material. Clearly, green spots in the size of 2 μm or smaller could be discerned, which were clearly absent in the FCC catalyst particle containing no zeolite Y. Based on this selective staining approach three industrially relevant deactivation methods, namely steaming (ST), two-step cyclic deactivation (CD) and Mitchel impregnation-steam deactivation (MI), have been evaluated, and compared with both fresh FCC and E-cat samples.


Fluid catalytic cracking: recent developments on the grand old lady of zeolite catalysis.

Vogt ET, Weckhuysen BM - Chem Soc Rev (2015)

Confocal fluorescence microscopy images showing the visualization of zeolite Y aggregate domains within an FCC catalyst particle with (a and b) and without (c and d) zeolite material. The images were obtained after reaction with thiophene (green) at 373 K and subsequent staining with Nile Blue (red) at 298 K. Images b and d are magnified views of the highlighted areas in a and c, respectively. (Reproduced with permission from ref. 175, Copyright Macmillan Publishers, 2011).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4594121&req=5

fig27: Confocal fluorescence microscopy images showing the visualization of zeolite Y aggregate domains within an FCC catalyst particle with (a and b) and without (c and d) zeolite material. The images were obtained after reaction with thiophene (green) at 373 K and subsequent staining with Nile Blue (red) at 298 K. Images b and d are magnified views of the highlighted areas in a and c, respectively. (Reproduced with permission from ref. 175, Copyright Macmillan Publishers, 2011).
Mentions: Buurmans, Ruiz-Martinez and coworkers175 have developed a set of selective staining reactions, which are catalyzed by Brønsted acid sites, making it possible to localize zeolite aggregate domains with a confocal fluorescence microscope. More specifically, various thiophene and styrene derivatives could be oligomerized selectively within the pores of zeolites Y and ZSM-5 embedded in an FCC catalyst matrix. As the resulting probe molecule oligomers have a distinct optical spectrum in the visible region of the spectrum, it was possible to excite the oligomers formed with an appropriate laser excitation in a confocal fluorescence microscope with a 2D spatial resolution of 500 nm. This selective staining approach is illustrated in Fig. 27 for two fresh FCC catalyst particles, one containing zeolite Y, whereas the other one was devoid in zeolite material. Clearly, green spots in the size of 2 μm or smaller could be discerned, which were clearly absent in the FCC catalyst particle containing no zeolite Y. Based on this selective staining approach three industrially relevant deactivation methods, namely steaming (ST), two-step cyclic deactivation (CD) and Mitchel impregnation-steam deactivation (MI), have been evaluated, and compared with both fresh FCC and E-cat samples.

Bottom Line: These trends include ways to make it possible to process either very heavy or very light crude oil fractions as well as to co-process biomass-based oxygenates with regular crude oil fractions, and convert these more complex feedstocks in an increasing amount of propylene and diesel-range fuels.In addition, we present an overview of the state-of-the-art micro-spectroscopy methods for characterizing FCC catalysts at the single particle level.These new characterization tools are able to explain the influence of the harsh FCC processing conditions (e.g. steam) and the presence of various metal poisons (e.g. V, Fe and Ni) in the crude oil feedstocks on the 3-D structure and accessibility of FCC catalyst materials.

View Article: PubMed Central - PubMed

Affiliation: Inorganic Chemistry and Catalysis Group, Debye Institute for Nanomaterials Science, Faculty of Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands. e.t.c.vogt@uu.nl b.m.weckhuysen@uu.nl.

ABSTRACT
Fluid catalytic cracking (FCC) is one of the major conversion technologies in the oil refinery industry. FCC currently produces the majority of the world's gasoline, as well as an important fraction of propylene for the polymer industry. In this critical review, we give an overview of the latest trends in this field of research. These trends include ways to make it possible to process either very heavy or very light crude oil fractions as well as to co-process biomass-based oxygenates with regular crude oil fractions, and convert these more complex feedstocks in an increasing amount of propylene and diesel-range fuels. After providing some general background of the FCC process, including a short history as well as details on the process, reactor design, chemical reactions involved and catalyst material, we will discuss several trends in FCC catalysis research by focusing on ways to improve the zeolite structure stability, propylene selectivity and the overall catalyst accessibility by (a) the addition of rare earth elements and phosphorus, (b) constructing hierarchical pores systems and (c) the introduction of new zeolite structures. In addition, we present an overview of the state-of-the-art micro-spectroscopy methods for characterizing FCC catalysts at the single particle level. These new characterization tools are able to explain the influence of the harsh FCC processing conditions (e.g. steam) and the presence of various metal poisons (e.g. V, Fe and Ni) in the crude oil feedstocks on the 3-D structure and accessibility of FCC catalyst materials.

No MeSH data available.