Catalytic Cracking Of Crude Oil Research Articles

Simulation of Hydrodynamics of the Riser Reactor for Catalytic Cracking of Crude Oil to Chemicals

Simulation of Hydrodynamics of the Riser Reactor for Catalytic Cracking of Crude Oil to Chemicals

Crude oil conversion to chemicals over green synthesized ZSM-5 zeolite

The study reports the conversion of crude oil to basic chemicals over a template-free green synthesis of ZSM-5(40) zeolite using halloysite (HAL) and bolus alpha (BA) as silica and alumina precursors. The Z(40)HAL and Z(40)BA exhibited hierarchical pores with high surface area of 248 m2/g and 257 m2/g, respectively. The addition of soft template during the synthesis of Z(40)BA forms a Z(40)BAT zeolite with lower surface area. The synthesized zeolites were impregnated with 2wt%Mn and tested for the steam catalytic cracking of crude oil to light olefins and aromatics catalysts at 675 °C in a fixed-bed reactor. Maximum light olefins (C2=-C4=) yield (47 wt%) and total aromatics (14.7 wt%) were attained over 2Mn/Z(40)HAL catalyst. The conversion of crude oil (68.4%) is attributed to hierarchical pores and the presence of large weak and strong acid sites in the 2Mn/Z(40)HAL zeolite. Moreover, due to the high reaction temperature, some effects of thermal cracking such as protolytic cracking reactions with high ethylene yield (22%) were introduced. The addition of 1% phosphorus and 1%Mn to Z(40)HAL resulted in lower catalytic cracking activity. Similarly, the 2Mn/Z(40)BAT performed slightly lower than the template-free 2Mn/Z(40)BA additive. The experimental results demonstrate the technical feasibility of template-free green synthesis of ZSM-5 zeolite in the conversion of crude oil to basic chemicals.

Steam catalytic cracking of crude oil over novel hierarchical zeolite–containing mesoporous silica–alumina core-shell catalysts

The direct conversion of crude oil to basic chemicals was studied over novel core-shell structured ZSM-5 zeolite containing mesoporous silica-alumina (MSA) composites. A template-directed sol-gel method in an alkaline medium was used to prepare a core-shell structured ZSM-5 containing MSA composites employing CTAB as template, tetraethyl orthosilicate (TEOS), and aluminum sulfate. This approach resulted in the formation of a uniform mesoporous silica-alumina shell around the zeolite crystal. The shell thickness (tune in the 8–26 nm range) and its alumina content were controlled by varying the TEOS/zeolite and TEOS/aluminum sulfate ratios. The physicochemical properties and steam catalytic cracking performance of Arab Extra Light (AXL) crude oil were investigated to enhance the yield of C2-C4 light olefins. For comparative study, conventional and mesoporous silica-alumina composites were mixed with kaolin (50%), steam deactivated (810 °C for 6 h) and tested in a fixed-bed reactor operated at 675 °C, residence time of 10 s and steam/oil ratio (g/g) of 0.5. The optimized mesoporous silica-alumina composite Z30 @ MSA (TEOS/zeolite = 0.85 and TEOS/aluminum sulfate = 15.86) had improved textural characteristics, moderate acidity, and AXL crude oil cracking potential at higher conversion (~70%) and selectivity towards light olefins (49.4%) than the unmodified ZSM-5(30). The mesoporous core-shell composite's distinct reaction pattern resulted in the formation of a unique mesoporous silica-alumina core-shell catalyst, which eased the rapid diffusion of desired products from intra-framework channels while inhibiting the formation of coke deposits.

Catalytic Cracking of Crude Oil: Mini Review of Catalyst Formulations for Enhanced Selectivity to Light Olefins

Catalytic Cracking of Crude Oil: Mini Review of Catalyst Formulations for Enhanced Selectivity to Light Olefins

One-step leap in achieving oil-to-chemicals by using a two-stage riser reactor: Molecular-level process model and multi-objective optimization strategy

With the demand for vehicle fuels (i.e., gasoline and diesel) is expected to decline soon, crude oil to chemical technology exhibits great potential to drive the next industry transition. This megatrend has led to studies on maximizing the production of low-carbon petrochemicals at the cost of fuels, which requires aggressive ways of converting oil into chemicals in a clean and efficient pattern. Herein, we proposed a novel process, termed OSCO, to crack naphtha, kerosene, diesel and heavy oil in a two-stage riser reactor efficiently, which can perform several refining procedures in the two-stage riser reactor vessel. A novel integration model of mixed fraction structure and molecular level is proposed. The multi-objective optimization strategies are also carried out to solve the optimization problem. As a result, the OSCO process can stably convert untreated heavy Daqing crude oil into light olefins with total yields of ethylene and propylene over 33 wt%, which also exhibits superior techno-economic, society, people's livelihood, and environmental performance. These insights may have a positive pushing role in engineering design, process intensification, and the optimization of direct catalytic cracking of crude oil.

Steam Catalytic Cracking of Crude Oil Over Novel Hierarchical Zeolite–Containing Mesoporous Silica–Alumina Core-Shell Catalysts

Steam Catalytic Cracking of Crude Oil Over Novel Hierarchical Zeolite–Containing Mesoporous Silica–Alumina Core-Shell Catalysts

Produce petrochemicals directly from crude oil catalytic cracking, a techno-economic analysis and life cycle society-environment assessment

Achieving direct catalytic cracking of crude oil to produce low-cost petrochemicals is a milestone technology for the transformation of refinery from “fuel type” to “chemical engineering type”. Herein, we first established the crude oil catalytic cracking process and identified the key process parameters affecting ethylene and propylene yields. Meanwhile, the crude oil direct steam cracking process was selected as a comparative process for the process economic, social and environmental performance by an improved life cycle society-environment assessment method. The improvement direction, suitable preheating temperature and higher cracking temperature, are given from the aspect of process though systematic integration and intensification. Results show the conversion rate of the catalytic cracking process is 86.10%, while the steam cracking process is only 76.71%. Furthermore, the utilization efficiency of carbon and hydrogen in the catalytic cracking process is 1.29 and 1.47 times higher than the steam cracking process, respectively. As for the society-economic performance, the catalytic cracking process provides up to 65% and 11% increase in net present value and total output value. As for the environmental performance, the catalytic cracking process consumes approximately 4% less non-renewable energy and has 31% less waste water generation. The results in this study harbour tremendous guiding significance to the design of crude oil directly efficient conversion to petrochemicals.

Investigation of metalloporphyrins in Duri crude oil asphaltene fraction

Metalloporphyrins are a compound that leads the contaminant in catalytic cracking of crude oil. This study aims to investigate the metalloporphyrin in crude oil from Duri, Riau, Indonesia. The extraction process yielded maltene and asphaltene up to 71.87 % and 1.07%, respectively. Asphaltene fraction was extracted by soxhlet using methanol solvent. The separation of asphaltene fraction was perfomed by column chromatography using mixing of toluene: chloroform: methanol (5:5:1) eluents. The Fourier Transform Infrared (FTIR) spectrum of asphaltene indicated the presence of a pyrolle ring at 800 cm−1 in the fingerprint region as a porphyrin-formed group. The UV-Vis absorption spectra of methanol separation showed free porphyrin at 580 nm and metalloporphyrins at 500–700 nm. The Microwave Plasma-Atomic Emission Spectrometer (MP-AES) qualitative analysis of asphaltene fraction showed the presence of vanadium, nickel, and iron. The Liquid Chromatography-Mass Spectrometry (LC-MS) analysis on asphaltene 15th fraction showed the presence of C34H39N4VO2 compound.

Oxidative cracking of crude oil by hydrogen peroxide in the presence of iron oxide nanoparticles

The interaction of hydrogen peroxide aqueous solutions with crude oil and high-boiling refined products, such as fuel oil and vacuum gas oil, in the presence of an oxidative cracking catalyst in the form of iron oxide nanosized particles is studied. This study is aimed at modeling processes occurring in the case of using hydrogen peroxide solutions in the catalytic cracking of crude oil. It is found that, in the presence of iron particles, the reaction of hydrogen peroxide decomposition causes the cracking of petroleum hydrocarbons. This process may be accompanied by reduction in the viscosity and density of crude oil and refined products. The reaction of catalytic cracking performed under these conditions leads to a marked increase in the fraction of light hydrocarbons in the composition of crude oil and high-boiling refined products.

Catalytic cracking of crude oil to light olefins and naphtha: Experimental and kinetic modeling

The direct catalytic cracking of three light crude oils have been evaluated over an equilibrated FCC catalyst (E-Cat) blended with MFI zeolite in a microactivity test unit at 550°C and catalyst/oil ratio between 1 to 4. At 60% conversion, the Super Light (ASL) crude oil yielded about 10wt.% C2–C4 olefins and 60wt.% naphtha over E-Cat, Extra Light (AXL) crude oil yielded 13wt.% light olefins and 52wt.% naphtha, while for Arab Light (AL) crude oil, light olefins and naphtha produced were 12 and 51wt.%, respectively. The addition of MFI with varying Si/Al molar ratio (Z30, Z280 and Z1500) to E-Cat increased the yield of light olefins with a maximum at 21.3wt.% for AXL over E-Cat/Z280. PIONA analysis of co-produced naphtha showed an increase in aromatics content over all additives with a maximum obtained from the cracking of AL over Z30 (91wt.%). Steam treatment of Z280 led to a slight change in the yield of light olefins and reduction of naphtha aromatics for the three types of crude oils. A four-lump kinetic model accurately predicted experimental yields of AL cracking over E-Cat and E-Cat/Z280 between 500°C and 550°C. From the kinetic model, the apparent activation energy for the conversion of naphtha to gases decreased from 21.2kcal/mol over E-Cat to 16.2kcal/mol over E-Cat/Z280 which indicates that Z280 facilitated the increased cracking of naphtha-range species to light olefins

Improved route from syngas to light olefins

A catalytic technique has promise as a new way of industrially producing olefins such as ethylene and propylene. Manufacturers use low-molecular-weight olefins to make plastics, solvents, paints, medicines, and other products. The largest-volume organic chemicals produced worldwide, these “light” olefins have traditionally been made, and are still primarily made, by catalytic cracking of crude oil. Because of high oil prices and petroleum conservation efforts in past years, researchers developed two technologies as alternatives to catalytic cracking: the MTO (methanol to olefins) process and the FTO (Fischer-Tropsch to olefins) process. These methods use zeolite and metal catalysts, respectively, to convert syngas, a mixture of hydrogen and carbon monoxide, to olefins. The OX-ZEO (oxide-zeolite) technique, developed by Xiulian Pan and Xinhe Bao of Dalian Institute of Chemical Physics and coworkers, provides a third alternative (Science 2016, DOI: 10.1126/science.aaf1835). The researchers optimized a catal...

Interaction of Probe Molecules with Bridging Hydroxyls of Two-Dimensional Zeolites: A Surface Science Approach

Bridging hydroxyls (Si–OH–Al) in zeolites are catalytically active for a multitude of important reactions, including the catalytic cracking of crude oil, oligomerization of olefins, conversion of methanol to hydrocarbons, and the selective catalytic reduction of NOx. The interaction of probe molecules with bridging hydroxyls was studied here on a novel two-dimensional zeolite model system consisting of an aluminosilicate forming a planar sheet of polygonal prisms, supported on a Ru(0001) surface. These bridging hydroxyls are strong Bronsted acid sites and can interact with both weak and strong bases. This interaction is studied here for two weak bases (CO and C2H4) and two strong bases (NH3 and pyridine), by infrared reflection absorption spectroscopy, in comparison with density functional theory calculations. Additionally, ethene is the reactant in the simplest case of the olefin oligomerization reaction which is also catalyzed by bridging hydroxyls, making the study of this adsorbed precursor state part...

Buildup of high solids flux conveying flow by coupling a moving bed to the riser bottom

Circulating fluidized bed (CFB) technology was first developed for the fluid catalytic cracking of crude oil in the 1940s, which is mainly characterized by circulating the solids between two adjacent fluidized vessels. Based on the CFB technology, dual fluidized bed gasification (DFBG) was proposed in the 1980s, but it received renewed interest in recent years as a high efficiency solids fuel gasification process for the production of high-quality syngas. In an autothermal DFBG system, heat transfer from the exothermal fluidized bed combustor to the endothermal fluidized bed pyrolyzer/gasifier, especially for pure steam gasification, relies on rapid and large solids circulation between the two vessels. A higher solids circulation rate, Gs, allows small temperature difference between the two reactors, thus making the operation and control of the DFBG system much easier. Transport bed gasification (TBG) is another newly developed thermochemical conversion method based on the CFB technology. The TBG process has the advantages of low tar evolution, modest reaction temperature, and high Correspondence concerning this article should be addressed to G. Xu at gwxu@ home.ipe.ac.cn

Gas and Solid Mixing in High-Density CFB Risers

Both gas and solids mixing and dispersion in circulating fluidized beds have been studied using steady and unsteady state tracer techniques. Most studies, however, have been conducted in CFB risers with relatively low solids circulation rates. In recent years, the high density and high solids flux CFB riser has received increasing attention due to its applications in catalytic cracking of crude oil and potential applications in catalytic reactions requiring high catalyst-to-reactant loading ratios. In view of the significantly different flow structure in high-density and high solid flux risers where annulus solids downward flow is no longer present as revealed in some recent studies, this paper analyzed the similarity and differences of gas and solids mixing behaviour between low density and high density CFB risers based on the data recently collected in our lab and data reported in the literature. It is shown that there exists a clear transition of both gas and solids axial mixing behaviour when the flow structure changes from low density to high density operating conditions, in correspondence to the disappearance of solids downward flow near the wall region. In the low density CFB risers with solids flux lower than ~250 kg/m2s, both gas and solids axial dispersion and backmixing increased with increasing solids flux and solids concentration. Beyond the transition to the dense suspension upflow regime, however, both gas and solids axial dispersions tend to decrease with increasing solids flux, indicating the development of gas and solids flow toward the plug flow resulting from the disappearance of solids downflow in the near wall region. Radial dispersion of gas and solids, on the other hand, showed a continuous decrease over a wide range of solids fluxes within both the low density and high density flow regions, indicating a reduced lateral exchange of gas and particles with increasing solids fluxes.

The Spatial and Temporal Variations of Polycyclic Aromatic Hydrocarbons (PAHs) in Environmental Matrices in the Czech Republic

The paper is a review of the PAH emission inventories and the results of ambient air measurements of PAHs on regional a local level and determination of PAHs in other abiotic and biotic samples in the Czech Republic (CR). The main sources of polycyclic aromatic hydrocarbons (PAHs) in the country are associated with electric and thermal energy production, waste incineration, road traffic and some industrial processes (e. g. high-temperature coal carbonation, catalytic cracking of crude oil and aluminium production).