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The research progress of heavy oil catalytic cracking technology at home and abroad is summarized from three aspects: the research survey of reaction mechanism of heavy oil catalytic cracking, the analysis and comparison of molecular sieve catalytic materials for heavy oil catalytic cracking, the technical characteristics and industrial application of different heavy oil catalytic cracking processes. Firstly, modified molecular sieve catalyst materials, small-crystal molecular sieves, hierarchical pore molecular sieves have become hot spots in current research and application, so as to strengthen the hydrothermal stability of catalyst, the intracrystalline diffusion and the graded cracking of heavy oil macromolecules in the hierarchical pores of the heavy oil catalytic cracking catalyst; secondly, based on the research of the carbonium ion mechanism and the free radical mechanism of the catalytic cracking reaction and the like, the reaction severity of heavy oil catalytic cracking technologies such as DCC, CPP, HCC, RTC and HSFCC is continuously improved, and in order to match the optimal reaction environment for different feeds, new reactor or multi-reactor combination technology has become the main direction of process technology research, which has achieved the purpose of improving the yield and selectivity of light olefins. [ABSTRACT FROM AUTHOR]

To improve the catalytic activity of zeolites in cracking of petroleum components for the production of light olefins, ZSM-5–USY composite catalysts modified with transition metals (e.g. Nb, Ni, or W) have been synthesized by an impregnation method. The catalytic performance of the obtained catalysts in the cracking of n-hexane as a model compound of petroleum for the production of light olefins has been evaluated using a fix-bed reactor. The Nb-modified composite zeolite has shown an excellent catalytic activity. The optimal Nb loading for the composite catalyst is 1.5% (1.5% Nb/Z–Y) that provides the highest amount of acid sites. The yield up to 50% and the selectivity up to 68% of the C2–C4 olefins have been achieved at 650°C. The kinetic study of the catalytic n-hexane cracking on 1.5% Nb/ZSM-5–USY has characterized it as the first-order reaction with the apparent activation energy of 115.16 kJ/mol. [ABSTRACT FROM AUTHOR]

Y Zeolite plays an irreplaceable role in many important applications due to its unique physicochemical properties, which has attracted extensive attention from researchers. Response surface methodology (RSM) was used to optimize the process parameters for the hydrothermal synthesis of Y zeolite using kaolin activated by microwave heating. The best relative crystallinity was 108.17% could be achieved at the condition: the aging temperature of guiding agent was 65 ℃, the crystallization temperature was 100 ℃, the crystallization time was 24 h. In addition, the aging temperature of guiding agent was the most important influence factor. Under the optimal condition, the SiO2/Al2O3 ratio of synthesized Y zeolite was 4.54, 90% of the particle size was less than 60 μm, and the specific surface area of Y zeolite was 479 m2/g. The successful preparation of Y zeolite with high crystallinity is expected to provide reference for the application of wastewater treatment, CO2 sequestration and fluid catalytic cracking for petroleum. [ABSTRACT FROM AUTHOR]

• EU-1 zeolite crystal sizes are shortened to nanoscale with the presence of TPOAC. • EU-1 nano zeolite aggregates expose more external acid sites and accessible volume. • Refining of EU-1 crystal sizes improves the accessibility and utilization degree of acid sites. • EU-1 nano zeolite aggregates show higher n-hexane cracking activity than parent EU-1. One-dimensional microporous zeolite, EU-1, exhibits more favorable selectivity of propylene in cracking of petroleum components. However, it faced the problem of low catalytic activity for the poor utilization of active sites. In this work, dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride (TPOAC) was used to functionalize protozeolitic units and inhibit the excessive growth of crystals by the long hydrophobic alkyl chain. The introduction of TPOAC decreased the crystal sizes into nanoscale, enhanced the mesoporous volume of EU-1 zeolite, and exposed more external acid sites. Moreover, TPOAC could interact with Al species, and in this case, fewer Al atoms were incorporated into the zeolite framework, reducing the acid strength and amount. Intelligent gravitation analyzer test indicated that the zeolite prepared with the presence of 0.30 g TPOAC exhibited the largest accessible volumes in n-hexane adsorption, and the highest accessibility of acid sites, which synergistically promoted cracking of n-hexane for the production of light olefins. [ABSTRACT FROM AUTHOR]

Fluid catalytic cracking (FCC) waste catalysts produced by petroleum cracking contain many harmful substances, such as heavy metals, and improper treatment can lead to environmental pollution. To solve this problem, this study investigated four types of FCC (LM, SH, A, SL) waste catalyst as a substitute filler for limestone mineral powder and examined their interactions with asphalt and fillers. The X-ray fluorescence (XRF), scanning electron microscope and specific surface area tests were conducted to compare the performance of FCC waste catalyst and fillers. Meanwhile, the effects of FCC waste catalyst on asphalt mastic composed of limestone mineral powder and asphalt were evaluated using surface energy, interaction parameters, and FTIR. Results show that there is little difference in the main components of the four waste FCC catalysts and limestone mineral powder. However, the surface roughness and specific surface area of the FCC catalysts are significantly greater than those of limestone. Moreover, the addition of FCC waste catalyst can improve the adhesion of asphalt with fillers and aggregates, and significantly enhance the interaction capabilities between the filler and the base asphalt, especially for SH. FTIR analysis confirms that the aforementioned improvements are achieved through physical interactions. This study reveals the effects of different FCC waste catalysts on asphalt mortar, and provides a theoretical basis for promoting the practical application of FCC waste catalysts in road engineering. [ABSTRACT FROM AUTHOR]

Two semi-synthetic clay-based catalysts were prepared. These catalysts were obtained by incorporating lanthanum oxide (Cat1) and chromium oxide (Cat2). They were then tested for catalytic cracking of a heavy petroleum residue (fuel). The two formulations were carried out in the presence of silica to improve their acidity then underwent an acid activation. The catalysts obtained were characterized by various methods (XRD, FTIR, ICP-OES, SEM). The results showed that the incorporation of oxides and the addition of silica improves the structural characteristics of the final products. The support used was a kaolinite rich clay, having a specific surface area of 15.26 m2/g and acidity of 14 meq/g. These values increase, respectively, to 456.14 m2/g and 50 meq/g for Cat1 and to 475.12 m2/g and 57 meq/g for Cat2. The influence of the type of oxide incorporated, the specific surface area, the porosity and the acidity of the catalysts on their catalytic activity was studied. The nature of the oxide used proved to be decisive on the quality of the catalyst. Thus Cat1, prepared with lanthanum oxide, showed the best performance in cracking the petroleum residue achieving a conversion rate of 74.13% compared to 66.53% for cat2. [ABSTRACT FROM AUTHOR]

Highlights • Hydrocracking and hydrotreating reactions kinetics are based on lumping technique. • The industrial model is validated with the performance of an experimental reactor. • Axial and radial dispersions are used to represent the slurry-phase reactor dynamic's. • Dynamic and steady-state simulations for hydrocracking of heavy oils are presented. • A sensitivity analysis of model parameters and operating conditions is presented. Abstract Modeling and simulation of a commercial size unit for hydrocracking of an atmospheric residue (312 °C+) in a slurry-phase reactor are reported. The model of the industrial reactor is formulated taking into account axial and radial gradients of the state variables: composition and temperature. The mathematical model was partially discretized with finite central differences in the positional derivatives generating a matrix system of ordinary differential equations which was solved by a Runge-Kutta method. The hydrocracking reaction kinetic model is based on lumping technique and hydrotreating reactions kinetics are described by Langmuir-Hinshelwood and power-law approaches. All the intrinsic kinetic parameters and correlations used in the simulations were taken from the literature. Dynamic and steady-state simulations were performed with the objective to find a distribution of composition and temperature in the reactor as a function of time. Also a parametric sensitivity study was elaborated in order to analyze the effects of uncertainties of model parameters in the dynamic and steady-state model responses. [ABSTRACT FROM AUTHOR]

The adsorption and reaction properties of heterogeneous zeolite catalysts (e.g. for catalytic cracking of petroleum, partial oxidation of natural gas) depend strongly on the types and distributions of Al heteroatoms in the aluminosilicate frameworks. The origins of these properties have been challenging to discern, owing in part to the structural complexity of aluminosilicate zeolites. Herein, combined solid‐state NMR and synchrotron X‐ray powder diffraction analyses show the Al atoms locate preferentially in certain framework sites in the zeolite catalyst Al‐SSZ‐70. Through‐covalent‐bond 2D 27Al{29Si} J‐correlation NMR spectra allow distinct framework Al sites to be identified and their relative occupancies quantified. The analyses show that 94 % of the Al atoms are located at the surfaces of the large‐pore interlayer channels of Al‐SSZ‐70, while only 6 % are in the sub‐nm intralayer channels. The selective siting of Al atoms accounts for the reaction properties of catalysts derived from SSZ‐70. [ABSTRACT FROM AUTHOR]

Highlights • The two breakdown types of coal by HVEP in air environment were found. • Liquid nitrogen adsorption, SEM and 3D-XRM results suggest that HVEP is a potential method for CBM extraction. • A new method for fracturing and permeability enhancing is proposed combining with the hydraulic fracturing and HVEP. Abstract In order to enhance the gas extraction rate of low-permeability coal seams, a study was made on variation characteristics of pore structure of the coal saturated by NaCl solution under the effect of high-voltage electrical pulses (HVEP) by adopting a self-designed experimental system of fracturing and permeability enhancing of the coal with HVEP. In addition, current waveforms in the process of electrical breakdown were also investigated. The results revealed the two types of electrical breakdown of the coal in air environment, namely, surface breakdown and internal breakdown with three forms of breakage, namely, complete comminution, breakage from one side and cracks on the surface. Furthermore, the coal was broken due to internal tension under the influence of HVEP. Based on energy dispersive spectroscopy (EDS) analysis, the coal underwent both physical and chemical changes where the current flowed. Results of scanning electron microscope (SEM) demonstrated that the higher the breakdown voltage, the more the fissures in coal, and the better the breakage effect. Fissures in the coal were observed via the 3D-XRM to extend radially from the center to boundary areas with the breakage effect weakening gradually from anode to cathode when needle electrode discharged. Besides, these fissures were interconnected with each other. The result of liquid nitrogen adsorption suggested that electrical breakdown could effectively boost gas desorption by improving fissures as well as pores and micropores in the coal. Characteristics of the current waveform showed that great thermal expansion stress was caused by huge energy injected into the coal in an instant. During the electrical breakdown of coal with the same voltage, the peak current was different which increased with the growing of breakdown voltage. [ABSTRACT FROM AUTHOR]

Abstract The main purpose of this study is to elucidate the effect of catalyst on asphaltene molecular structure during hydrocracking of C 5 -isolated asphaltene. Remained asphaltene and coke were obtained after hydrothermal and catalytic hydrothermal cracking of C 5 -isolated asphaltene at 380–430 °C, using 1000 ppm Mo from Mo-octoate precursor. XRD and NMR analyses were used to investigate the change of molecular structure of asphaltene during the reaction. It was revealed that aggregation of asphaltene increased with increasing the reaction severity resulted in coke formation. The presence of catalyst reduced the aggregation of asphaltene molecules in comparison with the hydrothermal cracking. It was also observed that the average number of stacked polyaromatic sheets in the remained asphaltene decreased with increasing the reaction temperature because of the transformation of high stacked asphaltene into coke during the reaction. Moreover, it was confirmed that the main reason for asphaltene aggregation was the reduction of steric hindrance of asphaltene molecules by the change in molecular structure of asphaltenes. [ABSTRACT FROM AUTHOR]

A study was carried out on the effect of ionic liquids (morpholine formate and aniline formate) on the desulfurization of catalytic cracking gasoline and coking gasoline. A relationship was found between the extent of desulfurization of the gasolines on the ionic liquid:gasoline ratio and the duration of the extraction. An increase in the ionic liquid: coking gasoline ratio from 1:10, to 1:5, and then 1:1 led to enhancement of desulfurization t o 19.5%, 21.5%, and 49%, respectively. An increase in the ionic liquid: catalytic cracking gasoline ratio from 1:3 to 1:1 led to an increase in the desulfurization of this gasoline from 40.2% to 65.4% for 0.2 h extraction time. When the extraction time was extended to 0.5 h, the desulfurization of catalytic cracking gasoline was enhanced from 50 to 70%. [ABSTRACT FROM AUTHOR]

Data are given on the cracking of vacuum gas oil with HY zeolite catalysts on aluminum pillared natural calcium montmorillonite under vigorous cracking conditions in laboratory reactors of different volumes with a fixed catalyst bed at 500-600°C. Increasing the cracking temperature and contact time of the vacuum gas oil with the catalyst was shown to increase the yield of the gas phase. The greatest gas yield was 42%. In this case, the gas contained C2 - C4 alkenes, including 28% propylene. We concluded that it should be possible to use aluminum pillared calcium montmorillonite as a component of a zeolite cracking catalyst for petrochemical processes. [ABSTRACT FROM AUTHOR]

In order to improve the quality of bio-oil and reduce the coking and deactivation of HZSM-5 molecular sieve catalyst in the catalytic cracking of bio-oil upgrading process, Non-Thermal Plasma (NTP) assisted HZSM-5 technical scheme was proposed, online upgrading of rape straw vacuum pyrolytic vapors were conducted in a fixed bed reactor to verify the effectiveness of the technology. In the research, the influence of catalyzing temperature, catalyst bed height, discharge power on the physicochemical properties of refined bio-oil were studied, and the yield of refined bio-oil was regarded as evaluation index, response surface methodology was adopted to optimize upgrading processing parameters. Chemical composition of the refined bio-oil which was obtained under optimized parameters was analyzed by GC–MS, and using thermogravimetric analysis, the impact of NTP on catalyst anti-coking property was evaluated. Research results indicates that catalyzing temperature, catalyst bed height and discharge power have significance effect on yield and physicochemical properties of refined bio-oil. With the optimized processing parameters of 392 °C catalyzing temperature, 34 mm catalyst bed height and 23.7 W discharge power, the oxygen content, high heating value and pH of refined bio-oil were respectively 19.79%, 33.14 MJ/kg and 4.98. Compared with original HZSM-5 catalytic upgrading method, the quality of refined bio-oil was improved obviously, and the amount of catalyst coke deposit reduced from 5.88% to 2.14%, the feasibility of NTP assisted HZSM-5 online upgrading bio-oil was confirmed. [ABSTRACT FROM AUTHOR]

The catalytic cracking of isopropylbenzene was investigaded over hybrid ZSM-12/MCM-41 and HZSM-12/MCM-48 micro-mesoporous materials, in order to verify the effect of the acid site of the accessibility of mesoporous channels combined with the acid sites into the zeolite. The hybrid materials were synthesized by the hydrothermal method using the template mechanism. The obtained materials were characterized by X-ray diffraction and BET isotherms using nitrogen adsorption-desorption at 77 K. The X-ray diffraction patterns presented characteristic peaks of the microporous and mesoporous phases. These analysis revealed the formation of ordered hexagonal MCM-41 or cubic MCM-48 mesoporous phases, associated with the ZSM-12 structure. In order to generate acid sites, the materials were ion exchanged with ammonium chloride solution. The calcined hybrid materials were tested as catalyst for cracking of isopropyl-benzene, using a fixed bed reactor at 450 oC and nitrogen gas. The catalytic tests showed that the HZSM-12/AlMCM-41 and HZSM-12/MCM-48 hybrid materials have potential for use in cracking reactions, bening more active than the zeolite or the M41S alone. The catalytic activities of the hybrid materials can be associated with a synergistic effect between the acid sites present on the zeolitic phase and the mesoporous phase. In order to verify how the structure of the hybrid materials may affect and control their catalytic performances, the results were compared with HZSM-12 physically mixed with MCM-41 and MCM-48. [ABSTRACT FROM AUTHOR]

Based on the characteristics of maximizing iso-paraffins (MIP) process and industrial data, an 8-lump kinetic model for MIP process is developed. And the 47 kinetic parameters of the model are calculated by Runge-Kutta method and genetic algorithm. It is seen that kinetic parameters show good consistence with the reaction mechanism of catalytic cracking. The average relative errors between calculated values and real values of product distribution are all below 5%. Then the model is modified by 14-7-5 type of back propagation (BP) neural network. As a result, the product distribution can be predicted more accurately by the hybrid model. Therefore, the combination of lump model and neural network can provide a new direction for simulation and optimization for heavy oil catalytic cracking. [ABSTRACT FROM AUTHOR]

Additives to a zeolite-containing cracking catalyst were synthesized and studied in order to enhance the resistance to the poisoning effect of nitrogen compounds (in particular indole) upon cracking of n-undecane as the model FCC hydrocarbon. The additives were represented by acid-activated clays and mixed oxides. The activation of clays in the catalyst by 5% sulfuric acid solutions was shown to enhance the resistance to nitrogen. The introduction of Mg, Al – mixed oxides in the catalytic system in the amount of 10 wt% increased its activity and resistance to indole. The highest resistance was observed for the systems containing magnesium‑aluminum oxides with a Me 2 + to Me 3 + molar ratio equal to 0.5: 1. Cobalt modification of these mixed oxides enhanced the activity and nitrogen resistance of the cracking catalysts. Use of such nitrogen-resistant catalysts will allow cracking of heavy raw materials. [ABSTRACT FROM AUTHOR]

Acidic bentonite clay was obtained through surface modification of bentonite clay using hydrochloric acid as acidic precursor to increase the acidity of the bentonite. The modified catalyst was examined via X-ray fluorescence (XRF), XRD analysis, Brunauer Emmett and Teller surface area (BET), FTIR analysis and temperature-programmed desorption (TPD) analysis. XRF analysis showed that the acid modification of bentonite clay results in an increase in the silica content and lower abundance of metal oxides, due to the dissolve of Fe 2 O 3 , MnO, CaO, Na 2 O. Ca 2+ , Na + cations from the interlayer and octahedral sheets. FTIR spectroscopy showed that the acid activation decreased the intensity of the absorption bands at 915, 875 and 836 cm −1 which arise from the binding modes of OH groups. NH 3 -TPD analysis showed a considerable increase in the moderate and strong Bronosted acid cites on the modified bentonite compared to the native clay. The modified bentonite was evaluated as economic and efficient heterogeneous catalyst in catalytic cracking process of two nonedible vegetable oils to obtain the corresponding biofuels at moderate processing temperature of 250–280 °C. It was observed that the catalytic conversion was preceded under mild temperature and obtained efficient biofuels with approved physical and fuel properties according to ASTM specifications. The role of the catalyst ratio was considerable on the yield percent and the properties of the obtained biofuels. The catalytic activity-reaction mechanism was discussed based on NH 3 -TPD analysis. [ABSTRACT FROM AUTHOR]

Vacuum residue cracking has been successfully conducted under supercritical water condition in presence of various metal oxide nanocalysts, namely NiO, CuO, ZnO, Co 2 O 3 , and Cr 2 O 3 synthesized at supercritical water. The cracking experiments were carried out at 450 °C. Three species of cracking: maltene, asphaltene, and coke were then weighed and their corresponding speciation was defined. Gas chromatography-mass spectrometry (GC–MS), nuclear magnetic resonance spectroscopy (NMR), thermogravimetric analysis (TGA), and elemental analysis (CHNS) tests were utilized to prove the performance of upgrading reactions. It was revealed that NiO showed the best performance among other catalyst, in which its activity and stability in catalytic cracking changed slightly. According to the results obtained from GC–MS, NMR, TGA, and CHNS anlyses, it was confirmed that the proportion of heavy hydrocarbons of products (i.e. non-catalytic and catalytic reactions) was lower than that of feedstock. [ABSTRACT FROM AUTHOR]

Heterogeneous Brønsted acid catalysts are tremendously important in industry, particularly in catalytic cracking processes. Here we show that these Brønsted acid sites can be directly observed at natural abundance by 17O DNP surface-enhanced NMR spectroscopy (SENS). We additionally show that the O−H bond length in these catalysts can be measured with sub-picometer precision, to enable a direct structural gauge of the lability of protons in a given material, which is correlated with the pH of the zero point of charge of the material. Experiments performed on materials impregnated with pyridine also allow for the direct detection of intermolecular hydrogen bonding interactions through the lengthening of O−H bonds. [ABSTRACT FROM AUTHOR]

Three-dimensional computational fluid dynamics simulations were performed to study gas flow, heat transfer, and catalytic reactions of vacuum gas oil inside spherical and ellipsoidal clusters consisting of fluid catalytic cracking catalyst particles. Simulation results with respect to gas flow inside the cluster and convective heat transfer between the gas and catalyst particle agreed well with results from the literature. Simulation results indicated that the gas stayed longer and had a higher temperature inside the cluster than that in the main stream, which intensified secondary reactions of gasoline species in the gas. At a higher cluster porosity, it was predicted that the gas could flow through the cluster with lower resistance and that secondary reactions lessened. [ABSTRACT FROM AUTHOR]

The riser reactor is the key unit in the fluid catalytic cracking (FCC) process. As the FCC feedstocks become heavier, the product mixture of oil, gas and catalysts must be separated immediately at the outlet of the riser to avoid excessive coking. The quick separation system is the core equipment in the FCC unit. China University of Petroleum (Beijing) has developed many kinds of separation system including the fender-stripping cyclone and circulating-stripping cyclone systems, which can increase the separation efficiency and reduce the pressure drop remarkably. For the inner riser system, a vortex quick separation system has been developed. It contains a vortex quick separator and an isolated shell. In order to reduce the separation time, a new type of separator called the short residence time separator system was developed. It can further reduce the separation time to less than 1 s. In this paper, the corresponding design principles, structure and industrial application of these different kinds of separation systems are reviewed. A system that can simultaneously realize quick oil gas separation, quick oil gas extraction and quick pre-stripping of catalysts at the end of the riser is the trend in the future. [ABSTRACT FROM AUTHOR]

Cracking residual fuel oil separated from a mixture of Azerbaijanian crude oils using catalysts based on aluminum plant sludges containing up to 50-70% FeO was investigated. It is shown that the yield of liquid products, including motor fuels, upon residual fuel oil cracking at 550 °C rises to 80 and 70 wt. %, respectively. Steam gasification of carbonized and partially reduced catalyst allows production of gas with hydrogen content of up to 72.84 vol. %. [ABSTRACT FROM AUTHOR]

Disposal of waste plastic and excessive use of fossil fuels have caused environmental problems in the world. According to an estimate, more than 100 million tonnes plastics are produced every year and after their usage these plastics are discarded to become waste. Both plastic- and petroleum-derived fuels are hydrocarbons that contain the elements of carbon and hydrogen. The main difference between these hydrocarbons is that plastic molecules have longer carbon chains than those of LPG, petrol and diesel fuels. Therefore, it is possible to convert waste plastic into fuels. Pyrolysis is a prospective method to handle waste plastics. The purpose of this study is to explore the ability of different types of catalysts in conversion of plastic waste to low-emissive hydrocarbon fuel. Pyrolysis experiments were conducted using three different catalysts to check their ability in increasing the production. Catalytic degradation with potato peels yielded 74.52 wt% liquid fuel product. So far, the use of potato peels as a biocatalyst in pyrolysis process has not been reported. The pyrolysis oil was analyzed by GC/MS to determine its elemental composition. The liquid products obtained were compatible with international standards. Therefore, two main global problems such as problem of waste plastic management and problem of shortage of fuel are being tackled together. [ABSTRACT FROM PUBLISHER]

Fluid catalytic cracking (FCC) catalysts play a central role in the chemical conversion of crude oil fractions. Using scanning transmission X-ray microscopy (STXM) we investigate the chemistry of one fresh and two industrially deactivated (ECAT) FCC catalysts at the single zeolite domain level. Spectro-microscopic data at the Fe L3, La M5, and Al K X-ray absorption edges reveal differing levels of deposited Fe on the ECAT catalysts corresponding with an overall loss in tetrahedral Al within the zeolite domains. Using La as a localization marker, we have developed a novel methodology to map the changing Al distribution of single zeolite domains within real-life FCC catalysts. It was found that significant changes in the zeolite domain size distributions as well as the loss of Al from the zeolite framework occur. Furthermore, inter- and intraparticle heterogeneities in the dealumination process were observed, revealing the complex interplay between metal-mediated pore accessibility loss and zeolite dealumination. [ABSTRACT FROM AUTHOR]

The physical interpretation of the J integral (i.e., J integral) is clear. J integral is the energy release rate associated with crack extension (i.e., translation of the crack in the x direction). However, the physical interpretation of the J integral remains unclear. In this study, different crack translations in the x direction were selected and tested by calculating the energy release rates associated with the crack translations and comparing them with the theoretical value of the J integral. [ABSTRACT FROM AUTHOR]

The problem of prompt speed and density profile mapping based on mathematical modeling of particle motion in the acceleration section of catalyst pneumotransport lines is discussed. An algorithm is developed to calculate the distribution of these parameters along the longitudinal coordinate of reactor-lifts to improve ergonomic efficiency of operation of reaction-regeneration systems used in oil refining and petrochemical industries. [ABSTRACT FROM AUTHOR]

With the aim of enhancing oil refining processes based on fluid catalytic cracking (FCC), the catalytic cracking of polycyclic aromatic hydrocarbons (PAHs) was investigated using an FCC catalyst consisting of a rare earth ion exchanged USY zeolite. In these trials, model PAHs were dissolved in n -hexadecane and were fed into a fixed bed microactivity test reactor operating at 516 °C. Reaction product analysis indicated very little cracking of the 2-ring PAH over the FCC catalyst, while in contrast the 3-ring PAH was highly reactive, and was rapidly converted into monocyclic aromatic hydrocarbons, 2-ring PAHs and coke. Tests using FCC catalysts with different rare earth loadings revealed that the loading amount has little effect on the conversion of the 3-ring PAH. In addition, catalysts containing USY zeolites with comparable unit cell sizes, and thus having comparable hydrogen transfer activities, exhibited similar catalytic activities for 3-ring PAH conversion, even though they contained different amounts of the rare earth metal oxide. This result suggests that the hydrogen transfer reaction plays an important role in 3-ring PAH conversion and that the main effect of rare earth loading is to maintain the hydrogen transfer activity of the catalyst by stabilizing the USY zeolite against steam deactivation. In summary, this study successfully demonstrated a potential FCC process for converting PAHs into useful light fractions without the necessity of employing a pressurized hydrogen atmosphere. [ABSTRACT FROM AUTHOR]

The maximizing iso-paraffins (MIP) process, a family craft of fluid catalytic cracking process, is designed to reduce olefin content and increase isoparaffin and aromatic content in gasoline. The authors propose a method used to predict the gasoline yield of MIP process. The prediction model with 17 input variables is based on generalized regression neural network and adaptive boosting (adaboost) algorithm. The mean square error between predictive gasoline yield and actual yield is 2.46. [ABSTRACT FROM PUBLISHER]

Phosphorus-modified ZSM-5 (P-ZSM-5) catalyst was active for steam cracking of n -hexane to produce propylene and ethylene; however, the P-ZSM-5 catalyst deactivated because of both dealumination and coke deposition, which were strongly influenced by the steam to n -hexane ratio in the reactant flow. The amount of coke deposition increased with decreasing the steam to n -hexane ratio from the TG-DTA measurement. The steam could reduce the reactions of the light olefins to BTX and coke and enhance the yield of the light olefins; however, the excess steam deactivated the ZSM-5 catalysts irreversibly via dealumination. [ABSTRACT FROM AUTHOR]

Fluid catalytic cracking (FCC) is an essential process for the conversion of gas oil to gasoline. This study is an effort to model the phenomenon numerically using commercial computational fluid dynamics (CFD) software, heavy density catalyst and 4-lump kinetic model. Geometry, boundary conditions and dimensions of industrial riser for catalytic cracking unit are conferred for 2D simulation using commercial CFD code FLUENT 6.3. Continuity, momentum, energy and species transport equations, applicable to two phase solid and gas flow, are used to simulate the physical phenomenon as efficient as possible. This study implements and predicts the use of the granular Eulerian multiphase model with species transport. Time accurate transient problem is solved with the prediction of mass fraction profiles of gas oil, gasoline, light gas and coke. The output curves demonstrate the breaking of heavy hydrocarbon in the presence of catalyst. An approach proposed in this study shows good agreement with the experimental and numerical data available in the literature. [ABSTRACT FROM AUTHOR]

This study aimed to prepare KF/CaO catalyst with high catalytic activity that can be applied to produce bio-fuel from Cornus wisoniana oil. The KF/CaO catalyst was characterized by Brunauer-Emmett-Teller surface area (BET), XRD, scanning electron microscopy (SEM), and temperature programmed desorption (TPD). The chemical compositions of C. wisoniana oil and bio-fuel oil were analyzed by GC-MS. The effect of the catalyst preparation conditions on catalytic activity was investigated. The optimal process conditions for the KF/CaO preparation were KF loading rate of 40%, calcination temperature of 600°C, and 4 h calcination time. Under the optimum process conditions, the bio-fuel yield reached 82.7 and 65% bio-fuel yield was obtained after being reused nine times. The bio-fuel oil obtained by catalytic cracking has similar chemical compositions to petroleum-based diesel, which exhibited good fuel properties. KF/CaO was used as a catalyst for the production of bio-fuel from cracking of Cornus wisoniana oil. [ABSTRACT FROM AUTHOR]

The development of alternative sources for energy and chemicals, particularly the use of plant biomass as a renewable resource for fuel or chemical feed stocks, has received much recent attention. The resin (biocrude) obtained fromPinus roxburghii, a resinous tree, was investigated as a potential source for liquid fuels in a fluidized bed reactor. The feed was studied for yield conversion data under different catalysts to feed ratio at different temperatures. High conversions of biocrude to liquid fuels were observed with maximum middle distillates selectivity at a catalyst/oil ratio of 1.8 and reaction temperature of 460°C. Gas chromatography analysis results indicated that the middle distillates obtained by catalytic cracking ofP. roxburghiibiocrude has a normal distribution of carbon number with high values from C10–C18carbon atoms. [ABSTRACT FROM PUBLISHER]

Developments in modeling of the fluid catalytic cracking (FCC) process have progressed along two lines. One emphasizes composition-based kinetic models based on molecular characterization of feedstocks and reaction products. The other relies on computational fluid dynamics. The aim is to develop an FCC model that strikes a balance between the two approaches. Specifically, we present an FCC riser model consisting of an entrance-zone and a fully developed zone. The former has four overlapping, fan-shaped oil sprays. The model predicts the plant data of Derouin et al. and reveals an inherent two-zone character of the FCC riser. Inside the entrance zone, cracking intensity is highest and changes rapidly, resulting in a steep rise in oil conversion. Outside the entrance zone, cracking intensity is low and varies slowly, leading to a sluggish increase in conversion. The two-zone model provides a computationally efficient modeling approach for FCC online control, optimization, and molecular management. © 2014 American Institute of Chemical Engineers AIChE J, 61: 610-619, 2015 [ABSTRACT FROM AUTHOR]

Catalytic cracking process of palm oil into bio-fuel using Ni/zeolite catalysts (2-10% wt. Ni) at various reaction temperatures (400-500 °C) in a flow-fixed bed reactor system has been carried out. Palm oil was pre-treated to produce methyl ester of palm oil as feedstock in the catalytic cracking reactions. The Ni/zeolite catalysts were prepared by wetness impregnation method using Ni(NO3)2 ⋅ 6H2O as the precursor. The products were collected and analysed using GC, GC-MS, and calorimeter. The effects of process temperatures and Ni content in Ni/zeolite have been studied. The results showed that Ni-2/zeolite could give a yield of 99.0% at 500 °C but only produced gasoline fraction of 18.35%. The physical properties of bio-fuel produced in this condition in terms of density, viscosity, flash point, and specific gravity were less than but similar to commercial fuel. The results of performance test in a 4-strike engine showed that the mixture of commercial gasoline (petrol) and bio-fuel with a ratio of 9:1 gave similar performance to fossil-based gasoline with much lower CO and O2 emissions and more efficient combustion. [ABSTRACT FROM AUTHOR]

Laboratory construction in universities directly effects on the quality of teaching, research and management, and it is a prerequisite for constructing the top-ranking university. Compared with the laboratory construction on macro perspective, the creating process of an entity laboratory is equally important. In this paper, the establishment for a small ACE-centered fluid catalytic cracking (FCC) refinery laboratory of East China Normal University was described in detail according to the laboratory layout, equipment purchase, equipment installation, laboratory run, testing of ACE's performance. And the laboratory was enriched and perfected after the latest three years running. [ABSTRACT FROM AUTHOR]

The oxides adsorbent of NiO/ZnO-Al2O3-SiO2was prepared by a co-precipitation method. NiO/ZnO-SiO2-Al2O3is an effective adsorbent for reactive adsorption desulfurization of fluid catalytic cracking gasoline. The reaction conditions, such as reaction temperature, total pressure, weight hourly space velocity, and volume ratio of hydrogen to oil for desulfurization over NiO/ZnO-SiO2-Al2O3in a fixed-fluidized bed reactor were investigated. With the optimum conditions, the sulfur content of FCC gasoline can be decreased from 180 to 11.6 mg·L−1, and the loss of olefin content of gasoline product is 1.05%, the research octane number loss of gasoline product is only 1.3 unit. [ABSTRACT FROM PUBLISHER]

Under laboratory conditions, nitrogen adsorption from the coking wax oil was studied respectively by D72 and D001-CC cationic activation resins as adsorbents in a continuous fixed bed reactor. Micro reaction system of fluid catalytic cracking unit was used to study the catalytic racking reaction performance of coking wax oil after denitrification. Adsorption properties of two kinds of activation resin were compared by studing the adsorption breakthrough curve in the fixed bed, the dynamic adsorption properties of alkaline nitrogen compounds in the coking wax oil and the affect of the adsorption temperature on the removal rate of basic nitrogen compounds. Catalytic cracking performances of coking wax oil before and after denitrification were finally compared with catalytic cracking experiments. Results of experiments showed that the optimum adsorption temperature of D001-CC activation resin was 70 °C, the adsorption capacity was saturated 6 hours later, and the saturated adsorption capacity is 19. 35 mg/g. The optimum adsorption temperature of D72 activation resin was 60 °C,the adsorption capacity was saturated 5 hours after, and the saturated adsorption capacity was 7. 75 mg/g. The degree of catalytic cracking of coking wax oil deepened and the conversion rate improved after dealing with the resin denitrification. When the reaction temperature was 400 °C, the conversion rate of coking wax oil without denitrification was 44%. The conversion rate of coking wax oil reached 81. 5% after 30 minute's adsorption denitrification treatment. The influences of alkaline nitrogen content on catalyst activity were more sensitive at higher reaction temperature. The more substantially decrease of alkaline nitrogen content in the coking wax oil, the more significantly increases of catalytic cracking conversion rates. [ABSTRACT FROM AUTHOR]

Abstract: This study provides new insights into fluid catalytic cracking (FCC) riser reactor from multi-scale viewpoint. The problem of simultaneous intraparticle molecule transfer and reaction, particle kinetics, and gas–solid flow in polydisperse FCC riser reactors was considered. A multi-scale CFD method was developed for constructing a multi-scale model to solve this problem. The multi-scale model consisted of a two-phase CFD model incorporating a single-particle model and a population balance model. The main flow field distribution parameters within the catalyst particles and reactors as well as the solid particle size distribution (PSD) could be calculated simultaneously based on intraparticle transfer and reaction using these models. The single-particle and multi-scale models were first verified and evaluated. Based on the validated models, intraparticle transfer limitations and/or flow fields in two size-scale FCC riser reactors were predicted. The simulations demonstrated three different reaction zones in FCC risers, and more elaborate mass, heat, and momentum transfer behaviors could be obtained. The simulations also demonstrated that particle kinetics (i.e., breakage and aggregation) have obvious influences on the FCC flow field in FCC risers; these effects have not been observed in conventional CFD models. [Copyright &y& Elsevier]

-Highlights: [•] The concentration of BrÃnsted and Lewis sites increases upon desilication. [•] Desilication with NaOH&TBAOH preserves the crystallinity of mesoporous Beta zeolite. [•] Cracking of gasoil over mesoporous Beta results in high propylene selectivity. [ABSTRACT FROM AUTHOR]

The development of alternate sources of energy, particularly the use of plants as renewable sources for fuel, has received much attention recently. The potential of two indigenous arid land petrocrops,E. royleanaandE. neriifolia, as a source of hydrocarbon fuels was explored. Biocrudes extracted from these plant species were catalytically upgraded to liquid fuels using fluidized catalytic cracking. Naphtha fractions obtained by cracking of biocrudes were analyzed to give the detailed and group-wise distribution of paraffinic, isoparaffinic, oleofinic, naphthenic, and aromatic components. These naphtha fractions are similar in composition to the naphtha obtained from petroleum crudes. [ABSTRACT FROM PUBLISHER]

Lump kinetics models and reaction mechanism of fluid catalytic cracking (FCC) gasoline are introduced. Nine lump kinetics model, eight lump kinetics model, ten lump kinetics model, thirteen lump kinetics model, seventeen lump kinetics model, and twenty lump kinetics model have been put forward on the basis of lump theory and the reaction mechanism. In the network, the aromatization reaction species were first lumped into 9, 8, 10, 13, 17, and 20 parts, respectively. A mathematical method is first introduced to calculate a lump model of FCC gasoline. The results from experimental data are in accordance with the quantitative analytical conclusions drawn from the calculated data. [ABSTRACT FROM PUBLISHER]

Learning from experience is one of the four pillars of Risk-Based Process Safety [CCPS, Guidelines for Risk Based Process Safety, New York, 2007]. Incidents that occur at one facility often provide opportunities to strengthen management systems at other facilities. Sharing the technical lessons learned from incidents is morally right and vital to improving process safety performance across the process and related industries. Most incidents also involve human factors, often as a key causal factor. Understanding these performance shaping factors can also be essential to minimizing future failures. Most articles regarding case studies on process safety incidents are written and presented by a third party who was not directly involved in the incident. As such, the articles may lack the human element and other insights that can only be properly appreciated and articulated by someone directly involved in the incident. In his early career the author was involved in two major incidents while managing the day-to-day operation of refinery process units. This article describes the first incident involving two major fires. In both incidents, the author found himself decidedly too close for comfort and could easily have become a casualty himself. This article will raise awareness of lessons learned relating to a number of elements of Risk-Based Process Safety [CCPS, Guidelines for Risk Based Process Safety, New York, 2007] and human factors. © 2013 American Institute of Chemical Engineers Process Saf Prog 32: 255-259, 2013 [ABSTRACT FROM AUTHOR]

Heat integration is commonly skipped when evaluating a process' relief systems design. Failing to evaluate the heat integration (or energy balance) for a process can result in overly conservative results and possibly lead to costly expenditures. Evaluating the effects of heat integration in relief systems design is a process that evaluates the physical limitations of the system and does not require taking credit for control system response. It is important to understand the effects that heat integration has on both individual relief devices, and in some cases, the significant affect it can have on flare system design. This becomes even more imperative in cases where relief devices that once discharged to the atmosphere are modified to discharge into a closed flare system. This article covers two examples where evaluating the effects of heat integration on the relief systems prevented costly modifications to those systems. © 2013 American Institute of Chemical Engineers Process Saf Prog, 32: 244-247, 2013 [ABSTRACT FROM AUTHOR]

A one dimensional dynamic model for a riser reactor in a fluidized bed catalytic cracking unit (FCCU) for gasoil feed has been developed in two distinct conditions, one for industrial FCCU and another for FCCU using various frequencies of microwave energy spaced at the height of the riser reactor (FCCU-MW). In addition, in order to increase the accuracy of component and bulk diffusion, instantaneous and overall fractional yield is used in a heuristic manner. Furthermore, the effect of various input temperatures on gasoline yield with FCCU-MW has been studied. The results of the convectional FCCU simulation show great compatibility with the plant data in hand. Comparison of the two models shows that microwave energy gives better results in terms of gasoline yield. Also it has been shown that the increase of feed temperature leads to the increase of gas oil conversion and especially gasoline yield. [ABSTRACT FROM AUTHOR]

Hydrogen peroxide desulfurization at 50°C of a catalytically cracked gasoline fraction containing methyl- and dimethylthiophenes and traces of benzothiophene and dibenzothiophene and boiling in the range of IBP-70°C in the presence of transition metal compounds NaMoO, NaWO, VOSO, and [Cu(NH)]CO followed by adsorption on alumina has been studied. The successive oxidation of the hydrocarbon fraction in the presence of the copper and molybdenum compounds under phase transfer conditions ensures the removal of up to 96% of total sulfur. [ABSTRACT FROM AUTHOR]

Abstract: ZSM-5 catalysts (C(X)-ZSM-5) with micropores and mesopores were prepared by a carbon templating method with a variation of carbon template content (X=0, 10, 20, 30, 40, and 50wt.%), and they were applied to the production of light olefins (ethylene and propylene) through catalytic cracking of C5 raffinate. The effect of carbon template content on the physicochemical properties and catalytic activity of C(X)-ZSM-5 catalysts was investigated. It was revealed that physicochemical properties of C(X)-ZSM-5 catalysts were strongly influenced by carbon template content. Adsorption ability for n-pentane and mesopore volume of C(X)-ZSM-5 catalysts increased with increasing carbon template content. It was also found that catalytic performance of C(X)-ZSM-5 catalysts was closely related to the mesoporosity of the catalyst. Conversion of C5 raffinate and yield for light olefins increased with increasing mesopore/micropore volume ratio of the catalyst, while selectivity for ethylene and propylene showed constant values. Thus, carbon template content in the C(X)-ZSM-5 catalysts strongly affected the mesoporosity of the catalyst, and in turn, mesoporosity played an important role in determining the catalytic performance in the production of light olefins through catalytic cracking of C5 raffinate. [Copyright &y& Elsevier]

Fluid catalytic cracking (FCC) is a dominant refining conversion process in China's most refineries. After decades of development, China has already become one of the major FCC technology licensors in the world. In this review, the research and development (R&D) activities on FCC riser termination device (RTD) technologies in China are reviewed and discussed. Emphasis is put on the R&D of a series of advanced RTD technologies led by China University of Petroleum, Beijing, which initiated in the early 1990s when more and more China's FCC units chose to process more residue feedstock. Followed by the guideline of three "quick"s and two "high"s, two early types of RTD systems with coupled zones for gas-solids centrifugal separation and pre-stripping were developed and applied successfully in commercial units. Significantly reduced yields of coke and dry gas due to restrained post-riser reactions and satisfactory particle recovery efficiency were achieved. These were the fender-stripper cyclone and vortex quick separator systems designed for external- and internal-riser FCC units, respectively. Later, further improvement efforts led to the development of another two RTD systems, i.e. the circulating-stripper cyclone system for external-riser units and super vortex quick separator system for internal-riser units. By now, nearly 50 applications were commissioned with a sum FCC capacity of 40.0 Mton/a, nearly one-third of China's total FCC processing capacity. Besides, other research efforts, such as the geometry optimization efforts on LD² type separator, the studies on RTD for down-flow riser FCC units, and the idea of non-disengager FCC unit are also discussed in this review. To accommodate to degraded feedstock, more stringent environmental regulations and new FCC process technologies, future R&D efforts on RTD technologies should be put on improvements to further satisfy the three-"quick"s and two-"high"s requirements with changing FCC operating conditions and different process requirements. [ABSTRACT FROM AUTHOR]