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J Paya - One of the best experts on this subject based on the ideXlab platform.
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geopolymers based on spent catalyst residue from a Fluid Catalytic Cracking fcc process
2013Co-Authors: J Paya, J Monzo, Erich D Rodriguez, Susan A Bernal, John L Provis, John D Gehman, Victoria M BorracheroAbstract:Abstract This paper assesses the use of alkali activation technology in the valorization of a spent Fluid Catalytic Cracking (FCC) catalyst, which is a residue derived from the oil-Cracking process, to produce ‘geopolymer’ binders. In particular, the effects of activation conditions on the structural characteristics of the spent catalyst-based geopolymers are determined. The zeolitic phases present in the spent catalyst are the main phases participating in the geopolymerization reaction, which is driven by the conversion of the zeolitic material to a highly Al-substituted aluminosilicate binder gel. Higher alkali content and SiO2/Na2O ratio lead to a denser structure with a higher degree of geopolymer gel formation and increased degree of crosslinking, as identified through 29Si MAS NMR. These results highlight the feasibility of using spent FCC catalyst as a precursor for geopolymer production.
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pozzolanic reaction rate of Fluid Catalytic Cracking catalyst residue fc3r in cement pastes
2013Co-Authors: J Paya, J Monzo, M V Borrachero, S VelazquezAbstract:Fluid Catalytic Cracking catalyst residue (FC3R) is a waste material generated in the petroleum industry. Previous research has shown that FC3R exhibits excellent pozzolanic properties in Portland cement mixtures. The pozzolanic activity of FC3R was studied by means of thermogravimetric analysis (measurement of lime fixation) and cold hydrochloric acid treatment (quantification of FC3R reacted). A water/binder ratio of 0·40 was used in the study in the preparation of a control paste (without spent catalyst) and a 15% substituted FC3R paste. The selected curing temperatures were 20 and 40°C and several curing times were tested. The amount (grammes) of fixed lime by gramme of reacted catalyst indicated that approximately one part lime is chemically combined with 2·3 parts of spent catalyst. The combination of both study techniques allows determination of the optimal dosage in order to maximise use of this excellent pozzolan.
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new geopolymeric binder based on Fluid Catalytic Cracking catalyst residue fcc
2012Co-Authors: M M Tashima, J Paya, J Monzo, Jorge Luis Akasaki, Vinicius N Castaldelli, L Soriano, M V BorracheroAbstract:Abstract This paper provides information about the synthesis and mechanical properties of geopolymers based on Fluid Catalytic Cracking catalyst residue (FCC). FCC was alkali activated with solutions containing different SiO 2 /Na 2 O ratios. The microstructure and mechanical properties were analysed by using several instrumental techniques. FCC geopolymers are mechanically stable, yielding compressive strength about 68 MPa when mortars are cured at 65 °C during 3 days. The results confirm the viability of producing geopolymers based on FCC.
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accelerated carbonation of cement pastes partially substituted with Fluid Catalytic Cracking catalyst residue fc3r
2009Co-Authors: E Zornoza, M V Borrachero, J Monzo, P Garces, J PayaAbstract:Abstract Accelerated carbonation tests have been carried out on Portland cement pastes and pastes partially substituted with a spent Fluid Catalytic Cracking catalyst (FC3R) to investigate possible differences between the composition of FC3R/cement and plain cement matrices. Cement/FC3R pastes have been tested by thermogravimetry and X-ray diffraction analyses. This study has revealed that the incorporation of FC3R on pastes produces a significant reduction of the alkaline reserve and an increase in the quantity of cementing products such as hydrated calcium silicoaluminates. The carbonation of cement/FC3R pastes leads to the total consumption of the porlandite of the paste. Further carbonation will produce the capture of the calcium contained in the cementitious phases, yielding calcium carbonate and silica and alumina gel. The main product of the carbonation process is calcite, but vaterite has also been detected in the carbonated pastes. No major differences were observed between the composition of FC3R/cement and plain cement pastes after the carbonation that could add additional risk to carbonation processes of FC3R-containing binders.
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the chemical activation of pozzolanic reaction of Fluid Catalytic Cracking catalyst residue fc3r in lime pastes
2007Co-Authors: J Paya, J Monzo, M V Borrachero, S VelazquezAbstract:Previous work has shown the effectiveness of certain chemical activators, especially sodium sulphate, in improving the pozzolanic activity of Fluid Catalytic Cracking catalyst residue (FC3R)/lime pastes, monitored by means of calcium hydroxide (CH) consumption. The influence of several chemical activators on the development of mechanical strength is described, namely sodium sulphate, calcium chloride, sodium hydroxide and NaOH– gypsum mixture. Since the study was performed in pastes, prismatic test specimens of 1 cm × 1 cm × 6 cm were used, which were proposed by Koch–Steinegger for durability studies of cement pastes. In order to evaluate the results, these were compared with the mechanical strength of mortars, and excellent correlations were obtained. The sodium sulphate activator gave very high compressive strengths, especially at early curing ages, although at longer curing ages, the paste without activator yielded satisfactory strength.
M V Borrachero - One of the best experts on this subject based on the ideXlab platform.
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pozzolanic reaction rate of Fluid Catalytic Cracking catalyst residue fc3r in cement pastes
2013Co-Authors: J Paya, J Monzo, M V Borrachero, S VelazquezAbstract:Fluid Catalytic Cracking catalyst residue (FC3R) is a waste material generated in the petroleum industry. Previous research has shown that FC3R exhibits excellent pozzolanic properties in Portland cement mixtures. The pozzolanic activity of FC3R was studied by means of thermogravimetric analysis (measurement of lime fixation) and cold hydrochloric acid treatment (quantification of FC3R reacted). A water/binder ratio of 0·40 was used in the study in the preparation of a control paste (without spent catalyst) and a 15% substituted FC3R paste. The selected curing temperatures were 20 and 40°C and several curing times were tested. The amount (grammes) of fixed lime by gramme of reacted catalyst indicated that approximately one part lime is chemically combined with 2·3 parts of spent catalyst. The combination of both study techniques allows determination of the optimal dosage in order to maximise use of this excellent pozzolan.
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new geopolymeric binder based on Fluid Catalytic Cracking catalyst residue fcc
2012Co-Authors: M M Tashima, J Paya, J Monzo, Jorge Luis Akasaki, Vinicius N Castaldelli, L Soriano, M V BorracheroAbstract:Abstract This paper provides information about the synthesis and mechanical properties of geopolymers based on Fluid Catalytic Cracking catalyst residue (FCC). FCC was alkali activated with solutions containing different SiO 2 /Na 2 O ratios. The microstructure and mechanical properties were analysed by using several instrumental techniques. FCC geopolymers are mechanically stable, yielding compressive strength about 68 MPa when mortars are cured at 65 °C during 3 days. The results confirm the viability of producing geopolymers based on FCC.
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accelerated carbonation of cement pastes partially substituted with Fluid Catalytic Cracking catalyst residue fc3r
2009Co-Authors: E Zornoza, M V Borrachero, J Monzo, P Garces, J PayaAbstract:Abstract Accelerated carbonation tests have been carried out on Portland cement pastes and pastes partially substituted with a spent Fluid Catalytic Cracking catalyst (FC3R) to investigate possible differences between the composition of FC3R/cement and plain cement matrices. Cement/FC3R pastes have been tested by thermogravimetry and X-ray diffraction analyses. This study has revealed that the incorporation of FC3R on pastes produces a significant reduction of the alkaline reserve and an increase in the quantity of cementing products such as hydrated calcium silicoaluminates. The carbonation of cement/FC3R pastes leads to the total consumption of the porlandite of the paste. Further carbonation will produce the capture of the calcium contained in the cementitious phases, yielding calcium carbonate and silica and alumina gel. The main product of the carbonation process is calcite, but vaterite has also been detected in the carbonated pastes. No major differences were observed between the composition of FC3R/cement and plain cement pastes after the carbonation that could add additional risk to carbonation processes of FC3R-containing binders.
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the chemical activation of pozzolanic reaction of Fluid Catalytic Cracking catalyst residue fc3r in lime pastes
2007Co-Authors: J Paya, J Monzo, M V Borrachero, S VelazquezAbstract:Previous work has shown the effectiveness of certain chemical activators, especially sodium sulphate, in improving the pozzolanic activity of Fluid Catalytic Cracking catalyst residue (FC3R)/lime pastes, monitored by means of calcium hydroxide (CH) consumption. The influence of several chemical activators on the development of mechanical strength is described, namely sodium sulphate, calcium chloride, sodium hydroxide and NaOH– gypsum mixture. Since the study was performed in pastes, prismatic test specimens of 1 cm × 1 cm × 6 cm were used, which were proposed by Koch–Steinegger for durability studies of cement pastes. In order to evaluate the results, these were compared with the mechanical strength of mortars, and excellent correlations were obtained. The sodium sulphate activator gave very high compressive strengths, especially at early curing ages, although at longer curing ages, the paste without activator yielded satisfactory strength.
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chemical activation of pozzolanic reaction of Fluid Catalytic Cracking catalyst residue fc3r in lime pastes thermal analysis
2004Co-Authors: J Paya, J Monzo, M V Borrachero, S VelazquezAbstract:In this paper, the role and reactivity of Fluid Catalytic Cracking catalyst residue (FC3R) as a pozzolanic mineral admixture are studied. For that purpose, thermogravimetric (TG) studies of several FC3R/lime pastes, activated by using different chemical compounds (NaOH, gypsum, CaCl2 and Na2SO4), were performed. First, lime fixation and the nature of the hydration products were characterised from TG curves. Second, sodium sulphate was considered as the best chemical activator in the lime fixation process, yielding a 100% of fixed lime for short curing periods. In addition, hydrated gehlenite crystals incorporating sulphate ions were identified, mainly in cured pastes. From these experimental studies, it can be concluded that FC3R is a very good pozzolanic material for inclusion in lime pastes and mortars, and the addition of a small amount of Na2SO4 and CaCl2 enhanced the reactive ability of FC3R with hydrated lime.
Bert M Weckhuysen - One of the best experts on this subject based on the ideXlab platform.
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a dnp supported solid state nmr study of carbon species in Fluid Catalytic Cracking catalysts
2017Co-Authors: Deni Mance, Florian Meirer, Bert M Weckhuysen, Johan Van Der Zwan, Marjolein E Z Velthoen, Marc Baldus, Eelco T C VogtAbstract:A combination of solid-state NMR techniques supported by EPR and SEM-EDX experiments was used to localize different carbon species (coke) in commercial Fluid Catalytic Cracking catalysts. Aliphatic coke species formed during the Catalytic process and aromatic coke species deposited directly from the feedstock respond differently to dynamic nuclear polarization signal enhancement in integral and crushed FCC particles, indicating that aromatic species are mostly concentrated on the outside of the catalyst particles, whereas aliphatic species are also located on the inside of the FCC particles. The comparison of solid-state NMR data with and without the DNP radical at low and ambient temperature suggests the proximity between aromatic carbon deposits and metals (mostly iron) on the catalyst surface. These findings potentially indicate that coke and iron deposit together, or that iron has a role in the formation of aromatic coke.
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Fluid Catalytic Cracking recent developments on the grand old lady of zeolite catalysis
2015Co-Authors: Eelco T C Vogt, Bert M WeckhuysenAbstract: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.
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x ray fluorescence tomography of aged Fluid Catalytic Cracking catalyst particles reveals insight into metal deposition processes
2015Co-Authors: Samanbir Kalirai, Florian Meirer, Ulrike Boesenberg, Gerald Falkenberg, Bert M WeckhuysenAbstract:Microprobe X-ray fluorescence tomography was used to investigate metal poison deposition in individual, intact and industrially deactivated Fluid Catalytic Cracking (FCC) particles at two differing Catalytic life-stages. 3 D multi-element imaging, at submicron resolution was achieved by using a large-array Maia fluorescence detector. Our results show that Fe, Ni and Ca have significant concentration at the exterior of the FCC catalyst particle and are highly co-localized. As concentrations increase as a function of Catalytic life-stage, the deposition profiles of Fe, Ni, and Ca do not change significantly. V has been shown to penetrate deeper into the particle with increasing Catalytic age. Although it has been previously suggested that V is responsible for damaging the zeolite components of FCC particles, no spatial correlation was found for V and La, which was used as a marker for the embedded zeolite domains. This suggests that although V is known to be detrimental to zeolites in FCC particles, a preferential interaction does not exist between the two.
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agglutination of single catalyst particles during Fluid Catalytic Cracking as observed by x ray nanotomography
2015Co-Authors: Florian Meirer, Samanbir Kalirai, Nelson J Weker, Yang Liu, Joy C Andrews, Bert M WeckhuysenAbstract:Metal accumulation at the catalyst particle surface plays a role in particle agglutination during Fluid Catalytic Cracking.
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high resolution single molecule fluorescence imaging of zeolite aggregates within real life Fluid Catalytic Cracking particles
2015Co-Authors: Zoran Ristanovic, Marleen M Kerssens, Alexey V Kubarev, Frank C Hendriks, Peter Dedecker, Johan Hofkens, Maarten B J Roeffaers, Bert M WeckhuysenAbstract:Fluid Catalytic Cracking (FCC) is a major process in oil refineries to produce gasoline and base chemicals from crude oil fractions. The spatial distribution and acidity of zeolite aggregates embedded within the 50–150 μm-sized FCC spheres heavily influence their Catalytic performance. Single-molecule fluorescence-based imaging methods, namely nanometer accuracy by stochastic chemical reactions (NASCA) and super-resolution optical fluctuation imaging (SOFI) were used to study the Catalytic activity of sub-micrometer zeolite ZSM-5 domains within real-life FCC catalyst particles. The formation of fluorescent product molecules taking place at Bronsted acid sites was monitored with single turnover sensitivity and high spatiotemporal resolution, providing detailed insight in dispersion and Catalytic activity of zeolite ZSM-5 aggregates. The results point towards substantial differences in turnover frequencies between the zeolite aggregates, revealing significant intraparticle heterogeneities in Bronsted reactivity.
J Monzo - One of the best experts on this subject based on the ideXlab platform.
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geopolymers based on spent catalyst residue from a Fluid Catalytic Cracking fcc process
2013Co-Authors: J Paya, J Monzo, Erich D Rodriguez, Susan A Bernal, John L Provis, John D Gehman, Victoria M BorracheroAbstract:Abstract This paper assesses the use of alkali activation technology in the valorization of a spent Fluid Catalytic Cracking (FCC) catalyst, which is a residue derived from the oil-Cracking process, to produce ‘geopolymer’ binders. In particular, the effects of activation conditions on the structural characteristics of the spent catalyst-based geopolymers are determined. The zeolitic phases present in the spent catalyst are the main phases participating in the geopolymerization reaction, which is driven by the conversion of the zeolitic material to a highly Al-substituted aluminosilicate binder gel. Higher alkali content and SiO2/Na2O ratio lead to a denser structure with a higher degree of geopolymer gel formation and increased degree of crosslinking, as identified through 29Si MAS NMR. These results highlight the feasibility of using spent FCC catalyst as a precursor for geopolymer production.
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pozzolanic reaction rate of Fluid Catalytic Cracking catalyst residue fc3r in cement pastes
2013Co-Authors: J Paya, J Monzo, M V Borrachero, S VelazquezAbstract:Fluid Catalytic Cracking catalyst residue (FC3R) is a waste material generated in the petroleum industry. Previous research has shown that FC3R exhibits excellent pozzolanic properties in Portland cement mixtures. The pozzolanic activity of FC3R was studied by means of thermogravimetric analysis (measurement of lime fixation) and cold hydrochloric acid treatment (quantification of FC3R reacted). A water/binder ratio of 0·40 was used in the study in the preparation of a control paste (without spent catalyst) and a 15% substituted FC3R paste. The selected curing temperatures were 20 and 40°C and several curing times were tested. The amount (grammes) of fixed lime by gramme of reacted catalyst indicated that approximately one part lime is chemically combined with 2·3 parts of spent catalyst. The combination of both study techniques allows determination of the optimal dosage in order to maximise use of this excellent pozzolan.
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new geopolymeric binder based on Fluid Catalytic Cracking catalyst residue fcc
2012Co-Authors: M M Tashima, J Paya, J Monzo, Jorge Luis Akasaki, Vinicius N Castaldelli, L Soriano, M V BorracheroAbstract:Abstract This paper provides information about the synthesis and mechanical properties of geopolymers based on Fluid Catalytic Cracking catalyst residue (FCC). FCC was alkali activated with solutions containing different SiO 2 /Na 2 O ratios. The microstructure and mechanical properties were analysed by using several instrumental techniques. FCC geopolymers are mechanically stable, yielding compressive strength about 68 MPa when mortars are cured at 65 °C during 3 days. The results confirm the viability of producing geopolymers based on FCC.
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accelerated carbonation of cement pastes partially substituted with Fluid Catalytic Cracking catalyst residue fc3r
2009Co-Authors: E Zornoza, M V Borrachero, J Monzo, P Garces, J PayaAbstract:Abstract Accelerated carbonation tests have been carried out on Portland cement pastes and pastes partially substituted with a spent Fluid Catalytic Cracking catalyst (FC3R) to investigate possible differences between the composition of FC3R/cement and plain cement matrices. Cement/FC3R pastes have been tested by thermogravimetry and X-ray diffraction analyses. This study has revealed that the incorporation of FC3R on pastes produces a significant reduction of the alkaline reserve and an increase in the quantity of cementing products such as hydrated calcium silicoaluminates. The carbonation of cement/FC3R pastes leads to the total consumption of the porlandite of the paste. Further carbonation will produce the capture of the calcium contained in the cementitious phases, yielding calcium carbonate and silica and alumina gel. The main product of the carbonation process is calcite, but vaterite has also been detected in the carbonated pastes. No major differences were observed between the composition of FC3R/cement and plain cement pastes after the carbonation that could add additional risk to carbonation processes of FC3R-containing binders.
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the chemical activation of pozzolanic reaction of Fluid Catalytic Cracking catalyst residue fc3r in lime pastes
2007Co-Authors: J Paya, J Monzo, M V Borrachero, S VelazquezAbstract:Previous work has shown the effectiveness of certain chemical activators, especially sodium sulphate, in improving the pozzolanic activity of Fluid Catalytic Cracking catalyst residue (FC3R)/lime pastes, monitored by means of calcium hydroxide (CH) consumption. The influence of several chemical activators on the development of mechanical strength is described, namely sodium sulphate, calcium chloride, sodium hydroxide and NaOH– gypsum mixture. Since the study was performed in pastes, prismatic test specimens of 1 cm × 1 cm × 6 cm were used, which were proposed by Koch–Steinegger for durability studies of cement pastes. In order to evaluate the results, these were compared with the mechanical strength of mortars, and excellent correlations were obtained. The sodium sulphate activator gave very high compressive strengths, especially at early curing ages, although at longer curing ages, the paste without activator yielded satisfactory strength.
Wucheng Cheng - One of the best experts on this subject based on the ideXlab platform.
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characterization of iron contamination on equilibrium Fluid Catalytic Cracking catalyst particles
2018Co-Authors: Hui Jiang, Kenneth J T Livi, Shankhamala Kundu, Wucheng ChengAbstract:Abstract Iron poisoning is a well-known problem for Fluid Catalytic Cracking catalysts. To better understand this issue, several characterization techniques were used to examine a catalyst sample from a commercial unit. Under SEM-EDX, most cross sections of the catalyst particles exhibited iron nodule rims enriched with Fe, other contaminant metals, and Si. Scanning TEM X-ray mapping further confirmed that, compared to the inside of a catalyst particle, the surface layer was enriched in Si and contaminant metals, while depleted in Al. This catalyst had high frequency-dependent magnetic susceptibility, suggesting that some or all of the iron-bearing species should be in the nanometer size range. In TEM, the nodules were found to consist of Fe-bearing nanoparticles, imbedded in an amorphous matrix. The nanoparticles were also enriched in Mg, Ni or Ca, while the matrix was dominated by Si and minor Al. Selected area electron diffraction pattern indicated that these iron enriched nanoparticles had the spinel structure. These results should shed light on iron poisoning issues in FCC units.
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localization and speciation of iron impurities within a Fluid Catalytic Cracking catalyst
2017Co-Authors: Johannes Ihli, R R Jacob, Frank Krumeich, Wucheng Cheng, Dario Ferreira Sanchez, Vera Cuartero, O Mathon, Camelia N Borca, Thomas Huthwelker, Yuying ShuAbstract:Fluid Catalytic Cracking is a chemical conversion process of industrial scale. This process, utilizing porous catalysts composed of clay and zeolite, converts heavy crude-oil fractions into transportation fuel and petrochemical feedstocks. Among other factors iron-rich reactor and feedstream impurities cause these catalyst particles to permanently deactivate. Herein, we report tomographic X-ray absorption spectroscopy measurements that reveal the presence of dissimilar iron impurities of specific localization within a single deactivated particle. Whereas the iron natural to clay in the composite seems to be unaffected by operation, exterior-facing and feedstream-introduced iron was found in two forms. Those being minute quantities of ferrous oxide, located near regions of increased porosity, and impurities rich in Fe3+ , preferentially located in the outer dense part of the particle and suggested to contribute to the formation of an isolating amorphous silica alumina envelope.
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coke formation in the Fluid Catalytic Cracking process by combined analytical techniques
1997Co-Authors: Kuangnan Qian, Robert H Harding, Wucheng Cheng, Douglas C Tomczak, Edward F Rakiewicz, George Yaluris, And Xinjin Zhao, A W PetersAbstract:A combination of analytical techniques, including X-ray photoelectron spectroscopy (XPS), solid state 13C nuclear magnetic resonance (NMR) spectroscopy, and supercritical Fluid extraction/mass spectrometry (SFE/MS), were used to characterize the detailed composition and structure of coke formed on catalyst in the Fluid Catalytic Cracking (FCC) process. By characterizing coke samples from a series of designed FCC experiments, the effects of conversion on coke composition were systematically studied. SFE is shown to be an effective technique for removing low molecular weight coke molecules from the catalyst. When combined with mass spectrometry, the technique provided molecular level information of the extracted coke species. The coked catalysts were directly analyzed by XPS and NMR to obtain information relevant to surface and bulk coke structures, respectively. The study revealed the presence of two types of nitrogen-based coke and showed that N distributions were strongly affected by FCC conversion level...
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Fluid Catalytic Cracking selectivities of gas oil boiling point and hydrocarbon fractions
1996Co-Authors: Robert H Harding, X Zhao, Kuangnan Qian, And Kuppuswamy Rajagopalan, Wucheng ChengAbstract:The product selectivities of the Fluid Catalytic Cracking (FCC) process are strongly dependent on the properties of the petroleum gas oil reactant. In order to elucidate the complex relationship between gas oil chemical composition and product selectivity, a new technique has been developed which experimentally determines the product distribution of specific gas oil fractions in a realistic chemical environment. This incremental yield analysis approach is examined with a representative industrial gas oil. The gas oil is characterized and then divided into boiling point fractions by distillation and into hydrocarbon-type fractions with a chromatographic method. The FCC selectivity of each gas oil fraction is then determined by microactivity testing of blends of each fraction with the original gas oil. Results show that hydrocarbon type is a more significant determinant of the product spectrum than boiling point.
