Equilibrium Fluid Catalytic Cracking Catalyst Research Articles

Influence of oxidative conditions on the deactivation of an equilibrium FCC catalyst in the fast pyrolysis of HDPE in a conical spouted bed reactor

This study approaches the continuous catalytic fast pyrolysis of plastics in a flexible and original technology, i.e., a conical spouted bed reactor equipped with fountain confiner and draft tube. The catalyst is an inexpensive equilibrium fluid catalytic cracking (FCC) one. Moreover, operation under oxidative conditions is proposed to solve heat supply to the pyrolysis reactor, as a previous study revealed a remarkable difference in the performance of the cracking catalyst when pyrolysis was carried out under inert (conventional) and oxidative conditions. Therefore, the aim of this paper is to assess the role played in the catalyst stability and deactivation mechanism by the presence of air in the reaction environment. A comparative study has been conducted by operating in long continuous runs under the same conditions (550 °C and a space time of 15 gcatalyst min gHDPE−1) in inert and oxidative atmospheres, i.e., equivalence ratios (ER) of 0 and 0.2, respectively. The evolution of product distribution with time on stream was evaluated. Moreover, samples of catalysts were taken from the reactor at different reaction times to correlate catalyst performance with the deactivated catalyst properties, and therefore progress in the understanding of the deactivation mechanism. The amount and nature of the coke deposited on the catalyst and its influence on catalyst properties was ascertained using thermogravimetry (TG-TPO), Raman spectroscopy, and NH3 and N2 adsorption–desorption techniques. The operation under oxidative conditions improved product distribution, with higher yields of light olefins. Moreover, catalysts activity and stability were also enhanced under oxidative conditions. Therefore, the results obtained involve a step forward towards the scaling up of plastics continuous catalytic pyrolysis.

Characterization of Ni-Phases and Their Transformations in Fluid Catalytic Cracking (FCC) Catalysts: Comparison of Conventional Versus Boron-Based Ni-Passivation

Fluid Catalytic Cracking (FCC) has traditionally been a key refining process in generating transportation fuels. Recently, the focus on FCC has been further intensified as it plays an increasingly important role in the generation of key building blocks for the petrochemical industry. Nickel is considered as one of the most challenging contaminants in FCC and originates from Ni-containing compounds in petroleum fractions, not only during unit operation but also in handling of the equilibrium and spent catalysts. Despite this critical role it plays throughout the complete lifecycle of an FCC catalyst, the nature of Ni is not yet well understood at various stages of its journey after depositing on the catalyst surface. The main objective of this contribution is the qualitative and quantitative identification of the various possible phases of Ni that are usually present in an equilibrium FCC catalyst (Ecat). A series of conventional and advanced analytical techniques have been employed, including XRF, ICP-AES, PXRD, FT-IR, UV-Vis-NIR, SEM-EDS, TEM/HRTEM and STEM/EXDS, XPS, RAMAN and TPR-H2, on prototype Ni-impregnated SiO2, Al2O3 and USY zeolite samples, Ni-impregnated and lab-deactivated FCC samples, and equilibrium FCC catalysts obtained from different refineries. Detailed analysis of the obtained results on the basis of background information, showed the strengths and weaknesses of the various methods. It was shown that powder x-ray diffraction (pxrd) can be effectively used for the quantitative determination of the NiO (bunsenite) phase at levels representative of equilibrium FCC catalysts. A comparison of conventional versus boron-based Ni-passivation is presented. It was shown that catalysts from boron-based technology (BBT) can keep Ni at a less-reducible state, effectively hindering its deleterious role in FCC operations.

The role of catalyst acidity and shape selectivity on products from the catalytic fast pyrolysis of beech wood

The catalytic fast pyrolysis (CFP) of biomass represents an efficient integrated process to produce deoxygenated stable liquid fuels and valuable chemical products from lignocellulosic biomass. The zeolite ZSM-5 is a widely studied catalyst for the CFP process. However, its microporous structure may limit the diffusion of high molecular weight pyrolysis intermediates to its active sites. Mesoporous aluminosilicates such as Al-SBA-15 are promising materials with larger pore sizes that can overcome these diffusional limitations. Previous comparisons between mesoporous aluminosilicates and ZSM-5 for the CFP process have neglected the disproportionately high acidity of ZSM-5. In this study, an Al-SBA-15 catalyst has been synthesised with high acidity, comparable to that of a ZSM-5 catalyst with a Si:Al ratio of 15:1. The synthesised Al-SBA-15 catalyst was characterised by N2 physisorption, XRD and propylamine-TPD, and was compared to a ZSM-5 catalyst and a typical industrial equilibrium fluid catalytic cracking catalyst (e-FCC). All three catalysts were used at three different catalyst to biomass (C/B) ratios, to investigate the effect of varying concentrations of acid sites on the product distribution from the catalytic fast pyrolysis of beech wood. Interestingly, despite their dissimilar structural architectures, all three solid acid catalysts displayed similar reaction pathways towards the cracking of high molecular weight products such as levoglucosan and formation of intermediates including phenolics and furans. However, the selectivity towards the final catalytic products was dictated mainly by the structure of the catalysts. Despite their very similar surface area and acidity, the ZSM-5 exhibited high selectivity for the formation of desirable aromatic hydrocarbon products due to its shape-selective micropore structure, while Al-SBA-15 instead shifted the selectivity towards the formation of undesirable coke. The results highlighted the importance of catalyst shape-selectivity in the catalytic fast pyrolysis of biomass for the conversion of pyrolysis vapours into desirable products and the suppression of undesirable solid byproduct formation.

Towards understanding of phenolic compounds impact on Ni- and V-USY zeolites during bio-oils co-processing in FCC units

In this work, the n-heptane transformation was carried out in absence and presence of 1.2 wt% of guaiacol over Ni- and V-impregnated zeolites at 450 °C, to evaluate the influence of these metals on the poisoning effect of phenolic molecules during bio-oils and traditional Fluid Catalytic Cracking (FCC) feedstocks co-processing. Impregnation of the metals slightly decreased the Brønsted acid sites, but importantly increased the Lewis acidity. Notably, guaiacol was found to be less poisonous at shorter time-on-streams when Ni or V were present on the zeolite, as the metal-induced Lewis acidity seems to promote guaiacol transformation, which slows down coke formation from n-heptane. Simultaneously, unconverted guaiacol molecules adsorb mainly on the Lewis acid sites, resulting in a higher number of Brønsted acid sites available for the cracking reactions. Influence of Ni on the attenuation of the guaiacol deactivating effect was more important owing to the generation of a higher amount of metal-induced Lewis acid sites. Hence, taking into account the short contact times in the FCC riser, the presence of metal contaminants, such as Ni and V, on the FCC catalysts appears to be beneficial for the co-processing, being possibly one of the explanations for the lower impact of the phenolic compounds on the FCC equilibrium catalyst when compared to pure ultra-stable Y zeolites.

Hydrogen Transfer between Hydrocarbons and Oxygenated Compounds in Coprocessing Bio-Oils in Fluid Catalytic Cracking

Oxygenated model compounds representing typical components of bio-oils and a hydrocarbon hydrogen donor agent were used to study hydrogen transfer reactions between hydrocarbons and oxygenated compounds when coprocessed over acidic commercial fluid catalytic cracking (FCC) catalysts. Phenol, syringol, and trimethoxybenzene were each mixed with tetralin at 5 wt % individually in benzene as an inert solvent. The mixtures were reacted in a fluidized bed, batch CREC Riser Simulator laboratory reactor during 10 s contact time with a catalyst to oil relationship of 3 at 500 °C over a commercial equilibrium FCC catalyst, conditions being selected in order to simulate FCC bio-oil–vacuum gas oil coprocessing. Tetralin was also reacted alone at 5 wt % in benzene to gather background information. When tetralin was the only reactant, its conversion was 87%, the most important reactions being hydrogen transfer, as shown by the yield of naphthalene, and cracking. Alkylation and disproportionation were also observed to a lower extent. In the experiments with the mixtures, the oxygenated compounds converted completely and tetralin converted to less than half the conversion when pure. In these experiments, as compared to pure tetralin, the yield of gases and C11+ hydrocarbons increased and the yield of coke decreased, showing the interaction between the hydrocarbon and the model oxygenated compound reactants. The index SHT, which shows the selectivity to hydrogen transfer reactions from tetralin, increased significantly, to about 2 times, in the experiments with the mixtures. Moreover, coke from pure tetralin was shown to be qualitatively different from that in the experiments with the mixtures, where it was more condensed, thus confirming that the reaction pathways are dissimilar.

Effect of Fines Content on Fluidity of FCC Catalysts for Stable Operation of Fluid Catalytic Cracking Unit

Effect of fines content (weight % of particles with diameter less than 45 μm) on bed fluidity was determined to get a base for good fluidization quality in the fluid catalytic cracking (FCC) unit. The fines content in equilibrium FCC catalysts (Ecat) from commercial units were controlled by adding or removing the fines to simulate commercial situation. To get the fluidity values (Umb/Umf) of seven different FCC catalysts (2 Ecats and 5 fresh catalysts) and their mixture, minimum fluidization velocity (Umf) and minimum bubbling velocity (Umb) were measured in a fluidized bed reactor (0.05 m ID). The fluidity decreased with loss of fines content and increased with increments of makeup of fresh catalysts or additive with the controlled fines content. The fluidities of catalysts increase with increases of normalized particle diameter variation by the fines addition. The obtained fluidities have been correlated with the fines contents and the catalyst and gas properties. The proposed correlation could guide to keep good catalyst fluidity in the FCC unit.

Nine-lumped kinetic model for VGO catalytic cracking; using catalyst deactivation

A new nine-lumped kinetic model is proposed to describe the VGO catalytic cracking using equilibrium fluid catalytic cracking catalyst (E-CAT) modified with ZSM-5 and MCM-41 additives. The kinetic model contained 18 kinetic parameters and 2 parameters for the catalyst deactivation. The catalyst deactivation model was described by an exponential function of time on stream and temperature. Kinetic parameters were estimated based on experimental data at 500, 530, 550, 580, 600, and 620 °C by fourth order Runge–Kutta algorithm and genetic algorithm method. Frequency factors and apparent activation energies were calculated according to Arrhenius equation. The apparent activation energies were mainly in the range of 20–75 kJ mol−1. The apparent activation energies for VGO to LCO + slurry oil, gasoline and alkanes were much lower than the other cracking paths. The optimum operation temperature which led to the maximum gasoline yield and maximum propylene yield were 550 °C and 600 °C respectively. The deactivation constant which was described by Arrhenius model, resulted in frequency factor of 23,695 and activation energy of 65.198 kJ/mol.

Characterization of iron contamination on equilibrium fluid catalytic cracking catalyst particles

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.

Catalytic cracking of wax esters extracted from Euglena gracilis for hydrocarbon fuel production

Wax esters (WEs) synthesized by Euglena gracilis are potential sources for alternative fuels because of their high productivity, recent success in mass cultivation, and low energy consumption in extraction. In this study, deoxygenation of Euglena WE and conversion to hydrocarbons in a catalytic cracking process under a hydrogen-free atmosphere was investigated using a residue fluid catalytic cracking equilibrium catalyst with enhanced hydrogen-transfer activity. The deoxygenation of Euglena WE proceeded more rapidly with higher H2O selectivity than that of saturated triglycerides. This is because initial β-elimination of WEs produces saturated fatty acids and higher olefins; the higher olefins rapidly release hydrogen species during cracking, cyclization and aromatization, and the hydrogen species accelerate hydrodeoxygenation of the saturated fatty acids. Furthermore, the cracking of Euglena WE produced large amounts of paraffins and olefins instead of aromatics. Therefore, Euglena WE was confirmed to be a preferable feedstock for the catalytic cracking process for hydrocarbon fuel production.

Influence of Equilibrium Fluid Catalytic Cracking Catalyst Amount on the Thermolysis Process of Various Polyolefin Plastic Wastes in a Fixed-Bed Reactor for Gasoline and Diesel Production

The comprehensive study of waste industrial and automotive plastics [polypropylene (PP), polyethylene (PE), polystyrene (PS), ethylene-propylene copolymer (E/P), thermoplastic elastomer based on the ethylene–propylene–diene terpolymer and polypropylene (PP/EPDM)] thermolysis processes with 0%, 10%, and 25% of equilibrium fluid catalytic cracking (FCC) catalyst content was performed, and the catalyst suitability for the thermolysis process was evaluated. The experiments were carried out in the fixed-bed reactor. Reaction time and product yields depend on the ratio of a catalyst and a feedstock. The catalyst used leads to the formation of branched C7–C9 hydrocarbons as the main products as well as to the increased content of aromatic compounds. According to the liquid products composition, it was determined that catalyst acidity is excellent only for PE thermolysis and that the products obtained from this raw material are liquid only in case of catalytic thermolysis. Aromatization indexes, competitive parameter, the relative amounts of aromatization and isomerization reactions, and the ratio of unsaturated and saturated hydrocarbons were estimated for nonaromatic raw materials to evaluate mechanistic pathways of the processes. It was determined that catalytic reactions mainly occur at the lower temperature, and they run via a free-radical mechanism as the reaction temperature increases. The kinetic and thermodynamic parameters were also estimated for all raw materials using thermogravimetric data, which appeared dependent on the catalyst/polymer ratio and the plastic type used. The appropriate amount of catalyst for each raw material was determined for the production of diesel and gasoline cuts.

Kinetic modeling for catalytic cracking of pyrolysis oils with VGO in a FCC unit

A 5-lump kinetic model is proposed and validated to mean the catalytic cracking of pyrolysis oils with equilibrium fluid catalytic cracking catalyst (E-CAT) in an advanced cracking evaluation (ACE-R) FCC unit. In the present work a blend of fast pyrolysis oil (FPO) with vacuum gas oil (VGO); hydrodeoxygenated oil (HDO) with VGO; and VGO are used as raw materials. The kinetic modeling of lumped systems is carried out using a sequential approach. This approach decreased the number of simultaneous equations and hence estimated parameters. A 5-lump model, derived from 3- and 4-lumps, is used to represent the experimental data and used to estimate the kinetic constants and hence the yields of gasoline, LPG, dry gases, coke and feedstocks. In the sequential approach, the kinetic parameters have been estimated for a 3-lump model, and then the information is used to estimate the 4-lump parameters using a 4-lump model. Finally, the kinetic constants obtained from 4-lump are used to estimate the kinetic parameters for 5-lump model. A set of new experiments have been performed for catalytic cracking of pure VGO and coprocessing of FPO with VGO and HDO with VGO, by varying WHSV from 6 to 24h−1, at a constant reaction temperature and C/O ratio of 530°C and 5, respectively. The optimized process conditions were maintained to produce higher gasoline yield from VGO by catalytic cracking over equilibrium FCC catalyst. The process parameters obtained from lumped modeling, for catalytic cracking of pure VGO, have been compared with the kinetic parameters obtained from 4-lumped model available in the literature, and approximately 2% deviation were found in the products yields with respect to experimental data.

Fast pyrolysis oil from pinewood chips co-processing with vacuum gas oil in an FCC unit for second generation fuel production

Raw bio-oil produced from fast pyrolysis of pine woodchips was co-processed with standard Brazilian vacuum gasoil (VGO) and tested in a 200kg⋅h−1 fluid catalytic cracking (FCC) demonstration-scale unit using a commercial FCC equilibrium catalyst. Two different bio-oil/VGO weight ratios were used: 5/95 and 10/90.Co-processing of raw bio-oil in FCC was shown to be technically feasible. Bio-oil could be directly co-processed with a regular gasoil FCC feed up to 10wt%. The bio-oil and the conventional gasoil were cracked into valuable liquid products such as gasoline and diesel range products.Most of the oxygen present in the bio-oil was eliminated as water and carbon monoxide as these yields were always higher than that of carbon dioxide. Product quality analysis shows that trace oxygenates, primarily alkyl phenols, in FCC gasoline and diesel products are present with or without co-processing oxygenated intermediates. The oxygenate concentrations increase with co-processing, but have not resulted in increased concerns with quality of fuel properties.The presence of renewable carbon was confirmed in gasoline and diesel cuts through 14C isotopic analysis, showing that renewable carbon is not only being converted into coke, CO, and CO2, but also into valuable refining liquid products. Thus, gasoline and diesel could be produced from lignocellulosic raw materials through a conventional refining scheme, which uses the catalytic cracking process. The bio-oil renewable carbon conversion into liquid products (carbon efficiency) was approximately 30%, well above the efficiency found in literature for FCC bio-oil upgrading.

Experimental and kinetic study of catalytic cracking of heavy fuel oil over E-CAT/MCM-41 catalyst

The catalytic cracking of heavy fuel oil was investigated over the equilibrium fluid catalytic cracking catalyst (E-Cat) as a base component with the mesoporous MCM-41 as an additive. The catalytic performance of the E-Cat/MCM-41 system was assessed in a fixed-bed MAT unit. The reaction was performed at temperatures of 500, 530, 550 and 600°C and the product distributions in both gaseous and liquid phases were studied. The yields of products including light olefins, liquefied petroleum gas (LPG), gasoline, dry gas, coke and also the conversions obtained over different temperatures were reported and some generalities discussed. The maximum yield of propylene (17.5%) was obtained at 550°C whereas the highest conversion and gasoline yield was gained at 530°C. An eight-lump kinetic model containing 11 kinetic parameters was considered. Those parameters were estimated based on experimental data at specific temperatures by fourth order Runge–Kutta algorithm and the least square method. In addition, Arrhenius equation was used to calculate apparent activation energies. The calculated data of the product yields were in a close agreement with the experimental data.

Use of ZSM-5 catalyst in deoxygenation of waste cooking oil

AbstractThis study investigated the potential use of waste cooking oil (WCO) in the production of engine fuels and valuable chemicals via catalytic cracking. WCO was processed in its pure form and in a mixture with hydrotreated vacuum gas oil (HVGO). Catalytic cracking experiments were performed using a microactivity test (MAT) (simulation of the fluid catalytic cracking environment). In cracking over the standard fluid catalytic cracking equilibrium catalyst (FCC-ECAT), the oxygen contained in the feed was consumed in the formation of CO and CO

Catalytic Cracking of C2–C3 Carbonyls with Vacuum Gas Oil

The fluid catalytic cracking (FCC) route could be considered for the co-processing of biomass-derived pyrolysis oil with petroleum-derived vacuum gas oil (VGO) in a typical refinery unit by integrating it with a biomass fast pyrolysis process. This paper aims to study the effect of co-processing pyrolysis oil representative model compounds (C2–C3 carbonyls such as hydroxyacetone and glycolaldehyde dimer) with VGO in a FCC advanced cracking evaluation (ACE-R) unit, using an industrially available FCC equilibrium catalyst (E-CAT). The blending ratios of C2–C3 carbonyls and VGO were varied from 5:95, 10:90, 15:85, and 20:80. The reactor was operated in close to industrial FCC process at a temperature of 530 °C and atmospheric pressure with a catalyst-to-oil ratio of 5.0. The blended FCC feedstock and their liquid distillates were structurally characterized by 1H and gated decoupled 13C NMR techniques. The average structural parameters like branchiness index, substitution index, average length of alkyl chains, and fraction of aromaticity per molecule was obtained from NMR data. A linear increase in FCC conversion was observed with increase in hydroxyacetone blending ratio with VGO from 5% to 20%, which may be due to an increase in propylene and a decrease in heavy cycle oil. Increasing the glycolaldehyde blending ratio from 5% to 10% increased the FCC conversion, while the conversion decreased at ratios of 15% and 20%. The 1H NMR and 13C NMR data indicated that there is an increase in the amount of monoaromatics with increases in the amount of hydroxyacetone, whereas in the case of glycolaldehyde, the monoaromatics increased for blending ratios up to 10% and decreased upon further increases in blending ratio. The equilibrium FCC catalyst is capable of cracking oxygenates presents in pyrolysis oil such as hydroxyacetone and glycolaldehyde toward the production of liquefied petroleum gas (LPG) range products. Furthermore, a scheme has been proposed for the processing of pyrolysis oil in petroleum refinery units.

Back Cover: Characterization of a Fluidized Catalytic Cracking Catalyst on Ensemble and Individual Particle Level by X‐ray Micro‐ and Nanotomography, Micro‐X‐ray Fluorescence, and Micro‐X‐ray Diffraction (ChemCatChem 5/2014)

Many techniques, bigger picture The cover picture shows a combination of advanced characterization techniques: X-ray micro- and nanotomography and micro-X-ray fluorescence are used to characterize a commercial spent equilibrium fluid catalytic cracking catalyst at both the ensemble and individual particle level. In their Full Paper on p. 1427 ff., S. R. Bare et al. explain how the in-depth characterization study presents a robust methodology that provides an understanding of the equilibrium fluid catalytic cracking catalyst ECAT at both the micro- and nanometer scales.

Characterization of a Fluidized Catalytic Cracking Catalyst on Ensemble and Individual Particle Level by X‐ray Micro‐ and Nanotomography, Micro‐X‐ray Fluorescence, and Micro‐X‐ray Diffraction

AbstractA combination of advanced characterization techniques: synchrotron X‐ray micro‐ and nanotomography, micro‐X‐ray fluorescence, and micro‐XRD have been used to characterize a commercial spent equilibrium fluid catalytic cracking catalyst (ECAT) at both the ensemble and individual particle level. At the ensemble level, X‐ray microtomography was used to determine the average size, shape, and respective distributions of over 1200 individual catalyst particles. This information is important to determine performance in commercial operation. It is shown that a large fraction of the particles contained large internal voids (5–80 μm diameter), and these voids likely aid the accessibility for large hydrocarbon molecules. At the individual particle level, by using X‐ray nanotomography, these voids were visualized at a much smaller scale (≈100 nm–12 μm in diameter). In addition, the individual phases that are present in the particle, for example, TiO2 and clay, are readily visualized in 3 D. Micro‐X‐ray fluorescence (XRF) was used to map, and semiquantitatively determine, both the contaminant (Ni, V, Fe) and inherent (La) catalyst elemental distributions. The distribution of zeolite Y in the ECAT particle was inferred from the La XRF map. Micro‐XRD determined the lattice constant of the zeolite Y at the individual catalyst particle level. This in‐depth characterization study at the ensemble and individual ECAT particle level presents a robust methodology that provides an understanding of the ECAT at both the micro‐ and nanometer scales.

Development of new deactivation method for simulation of fluid catalytic cracking equilibrium catalyst

Selection of a good catalyst is the easiest way to increase profitability of a fluid catalytic cracking (FCC) unit. During operation, these catalysts get deactivated due to operation at high temperatures, steam and deposition of metals on the catalyst. Developing a proper catalyst deactivation method is crucial for optimization of a good catalyst for FCC. Conventional laboratory deactivation procedures include direct metal impregnation method, cyclic deactivation method (CDM) and cyclic propylene steaming (CPS). Direct metal impregnation method gives higher coke and gas yields. CDM and CPS methods implementation is very difficult and time-consuming and there is a deviation in coke and gas yield. New rapid deactivation method has been developed to simulate plant equilibrium catalyst (E-Cat) by modifying metal impregnation, steaming and oxidation/reduction procedures. The E-Cat generated through a new deactivation method was characterized for physico-chemical properties using X ray diffraction (XRD), temperature-programmed reduction (TPR), and SEM-EDX and activity studies. XRD studies show that metals are dispersed well on catalyst samples. SEMEDX studies reveal that the morphology of simulated E-Cat and plant E-Cat catalyst particles appear to be same. E-Cat obtained by new deactivation method gives better coke and gas yields. Two E-Cats were also generated through CDM and direct metal impregnation method for comparing with the one generated through new method. New deactivation method also significantly reduces the evaluation time and is cost-effective. New deactivation method is developed for the simulation of fluid catalytic cracking equilibrium catalyst in laboratory. New deactivation method significantly reduces catalyst evaluation and selection time and is more cost-effective.

Catalytic Cracking of Glycerol to Fine Chemicals over Equilibrium Fluid Catalytic Cracking Catalyst

Effective conversion of glycerol into fuels and chemicals is an emerging field in terms economic viability of first generation bio- fuels development. In the present work the refinery fluid catalytic cracking (FCC) process is used to convert the biomass -derived glycerol into possible fine chemicals through a series of reactions like dehydration, cracking and hydrogen transfer. The catalytic cracking of biomass–derived glycerol have been carried out using industrially available fluid catalytic cracking equilibrium catalyst (E-CAT) in an advanced cracking evaluation (ACE-R) FCC unit for temperatures ranging from 350 to 550°C. The catalyst-to-oil (C/O) ratio was kept constant at 5wt.%. At higher temperatures (430-550°C) 100% glycerol conversion and 50% of acetaldehyde yield was obtained with E-CAT. The maximum yield of acrolein was found to be 7.61% at 430°C temperature; whereas the yield of acetaldehyde was increased with increase in temperature and it was higher at 550°C. The gas and liquid products have been analyzed using gas chromatography (GC) and nuclear magnetic resonance (NMR) spectroscopy techniques, respectively. Carbon dioxide produced in the regeneration process was analyzed using infrared (IR) spectroscopy. Further in the liquid product, in addition to acetaldehyde and acrolein, light olefins and aromatics were also found.

Catalytic conversion of C4 fraction for the production of light olefins and aromatics

The catalytic conversion of the C4 fraction from a fluid catalytic cracking (FCC) unit over a commercial FCC equilibrium catalyst was investigated using a confined fluidized bed reactor system. Butenes were easier to convert than butanes, and 1-butene was the easiest to convert among the butene isomers. The ethene and propene yields increased with increased reaction temperature and decreased with increased weight hourly space velocity (WHSV). The formation of propene involved two successive steps: butene dimerization and large hydrocarbon cracking. Aromatics were formed by the aromatization of the intermediate large olefins. A mechanism parameter RCA was proposed to describe the relative function of the cracking reaction to the aromatization reaction. RCA increased with increased reaction temperature and decreased with increased WHSV. The cracking reaction predominates on the aromatization reaction at high reaction temperatures.