Cracking Of Heavy Oil Research Articles

ZrO2-impregnated red mud as a novel catalyst for steam catalytic cracking of vacuum residue

ZrO2-impregnated red mud catalysts were employed as a novel catalyst for catalytic cracking of vacuum residue with steam. Under the batch reaction condition at 470°C for 2h with superheated steam, 3wt% ZrO2-impregnated red mud exhibited the best performance for catalytic cracking of vacuum residue. Furthermore, under the same reaction conditions, the conversion and liquid yield of 3wt% ZrO2-impregnated red mud were higher than those of 3wt% ZrO2-supporting Al–FeOx, a well-known catalyst for catalytic cracking of heavy oil with steam. 3wt% ZrO2-impregnated red mud also showed better catalytic performance than 3wt% ZrO2-supporting Al–FeOx under the fixed-bed reaction conditions at 500°C for 2h with steam atmosphere, resulting in higher conversion as well as liquid yield. The better catalytic performance of 3wt% ZrO2-impregnated red mud was due to large surface area and high catalyst stability. The large surface area of 3wt% ZrO2-impregnated red mud could generate more active sites for hydrogenation, which induced higher H/C ratio in liquid product. X-ray diffraction data of the spent catalysts showed that iron oxide phase in 3wt% ZrO2-impregnated red mud maintained a hematite structure while it in 3wt% ZrO2-supporting Al–FeOx was transformed to magnetite, inactive phase for catalytic cracking.

Cracking of heavy oils using catalytic additives based on coal fly ash ferrospheres

Finding new low-cost catalysts, especially ones that can be used in cracking, is a problem of great interest in the refining of heavy oils. The activity of redox catalysts based on coal fly ash ferrospheres is examined for the cracking of two types of heavy oils (paraffin and asphaltenic), and for paraffin oil residue under autoclave conditions. It is established that at 450°C and with 10 wt % of ferrospheres, the selectivity of the formation of liquid products can be as high as 95–96% for paraffin oil and 72% for asphaltenic oil. The content of light products and the gasoline fraction increases in liquid products in comparison to thermal cracking. The effect of ferrospheres is most pronounced in the cracking of paraffin oil: the light fraction in the oil cracking products grows by approximately 20% relative to those obtained after thermal cracking, reaching almost 67%; the gasoline fraction in the light products of oil residue cracking grow by 14 times. The phase composition and structural characteristics of ferrospheres change during cracking, carbon compounds with different combustion reactivity are deposited on their surfaces, and concentrated sulfur compounds from heavy oils are observed.

Desulfurization of Heavy Oil with Iron Oxide-based Catalysts Using Steam

Desulfurization of heavy oil using steam was examined by catalytic cracking of atmospheric residual oil (AR) with iron oxide-based catalyst. The yield of hydrogen sulfide increased with higher ratio of steam to feedstock, whereas hydrogen sulfide was little produced in AR cracking without steam. Sulfur concentration of oil decreased to half that of feedstock, and some sulfur compounds were deposited on the catalyst. Oxidative cracking of heavy oil using oxygen species derived from steam produced hydrogen species from steam, so part of the hydrogen species reacted with heavy sulfur compounds on the catalyst to produce hydrogen sulfide, light sulfur compounds, and hydrocarbons. Some oxygen species could be transferred to sulfur dioxide. Therefore, hydrogenation and oxidation by the hydrogen and oxygen species derived from steam can cause desulfurization of AR. Cyclic sulfur compounds containing a thiophene ring in heavy oil are less reactive than acyclic sulfur compounds, so the reactivity of cyclic sulfur compounds was examined by catalytic cracking of dibenzothiophene. Dibenzothiophene was decomposed with the catalyst to produce carbon dioxide and hydrogen sulfide. Therefore, both acyclic and cyclic sulfur compounds can be decomposed with the catalyst and steam.

Catalytic Cracking of Heavy Oil with Iron Oxide-based Catalysts Using Hydrogen and Oxygen Species from Steam

Catalytic Cracking of Heavy Oil with Iron Oxide-based Catalysts Using Hydrogen and Oxygen Species from Steam

Studies on the Preliminary Cracking of Heavy Oils: The Effect of Matrix Acidity and a Proposal of a New Reaction Route

Viewpoints on the influence of matrix acidity on the catalytic cracking of heavy oil are still inconsistent, hindering the studies of the reaction routes that occur during the matrix-precracking process. In this study, the effects of matrix acidity on heavy oil cracking were systematically studied by preparing alumina and modified alumina with different acidity in a practically meaningful range as the matrix components of fluid catalytic cracking catalysts. Results showed that Bronsted sites presented a much higher activity than Lewis sites on the matrix surface. Increasing the Bronsted acid strength of matrices improved the activity of catalysts, with the aggravated product distribution, while increasing the Lewis acid strength of matrices aggravated the product distribution and decreased the catalyst activity. Interestingly, results also showed that contacting Lewis sites first followed by interacting with Bronsted sites during the matrix-precracking process would facilitate heavy oil cracking more deep...

Effect of cyclohexane as hydrogen-donor in ultradispersed catalytic upgrading of heavy oil

The incorporation of catalysts to enhance downhole upgrading in the Toe-to-Heel Air Injection (THAI) process is limited by deactivation due to coking arising from the cracking of heavy oil. This study aims to reduce the catalyst deactivation problems that can occur with upgrading of heavy oils. Ultradispersed catalyst particles could potentially replace pelleted catalysts which may be difficult to regenerate once deactivated during the THAI operation. The dispersed particles could potentially be applied once through, down-hole for in situ upgrading of heavy oil. The catalyst studied was finely crushed pelleted Ni–Mo/Al2O3 catalyst (2.4μm). The product distribution of liquid, coke and gas may be influenced by the presence of a suitable hydrogen source which promotes hydroconversion reactions rather than simple cracking. In order to improve liquid yield whilst suppressing coke formation, the effect of cyclohexane as hydrogen-donor solvent was studied in a stirred batch reactor (100mL) at temperature 425°C, initial pressure 17.5bar, agitation 500rpm, and a short reaction time of 10min. The use of cyclohexane was evaluated against that of hydrogen gas. The reaction under hydrogen atmosphere significantly reduced coke yield by 41.3% compared with a nitrogen environment under the same conditions. Also, the coke decreased by 6.2–45.4% as the cyclohexane:oil ratio increased from 0.01 to 0.08 (g·g−1) relative to 4.67wt.% of coke observed without added cyclohexane in ultradispersed catalytic upgrading under nitrogen environment. As the cyclohexane:oil ratio increases, the produced oil API gravity and middle distillate fractions (200–343°C) increase whilst the viscosity decreases. An estimated 0.073 CH:oil ratio was found to suppress coke formation in a similar manner to upgrading under hydrogen atmosphere at the same conditions.

The Catalyst Selectivity Index (CSI): A Framework and Metric to Assess the Impact of Catalyst Efficiency Enhancements upon Energy and CO2 Footprints

AbstractHeterogeneous catalysts are not only a venerable part of our chemical and industrial heritage, but they also occupy a pivotal, central role in the advancement of modern chemistry, chemical processes and chemical technologies. The broad field of catalysis has also emerged as a critical, enabling science and technology in the modern development of “Green Chemistry”, with the avowed aim of achieving green and sustainable processes. Thus a widely utilized metric, the environmental E factor—characterizing the waste-to-product ratio for a chemical industrial process—permits one to assess the potential deleterious environmental impact of an entire chemical process in terms of excessive solvent usage. As the many (and entirely reasonable) societal pressures grow, requiring chemists and chemical engineers not only to develop manufacturing processes using new sources of energy, but also to decrease the energy/carbon footprint of existing chemical processes, these issues become ever more pressing. On that road to a green and more sustainable future for chemistry and energy, we note that, as far as we are aware, little effort has been directed towards a direct evaluation of the quantitative impacts that advances or improvements in a catalyst’s performance or efficiency would have on the overall energy or carbon (CO2) footprint balance and corresponding greenhouse gas (GHG) emissions of chemical processes and manufacturing technologies. Therefore, this present research was motivated by the premise that the sustainability impact of advances in catalysis science and technology, especially heterogeneous catalysis—the core of large-scale manufacturing processes—must move from a qualitative to a more quantitative form of assessment. This, then, is the exciting challenge of developing a new paradigm for catalysis science which embodies—in a truly quantitative form—its impact on sustainability in chemical, industrial processes. Towards that goal, we present here the concept, definition, design and development of what we term the Catalyst Sensitivity Index (CSI) to provide a measurable index as to how efficiency or performance enhancements of a heterogeneous catalyst will directly impact upon the fossil energy consumption and GHG emissions balance across several prototypical fuel production and conversion technologies, e.g. hydrocarbon fuels synthesized using algae-to-biodiesel, algae-to-jet biofuel, coal-to-liquid and gas-to-liquid processes, together with fuel upgrading processes using fluidized catalytic cracking of heavy oil, hydrocracking of heavy oil and also the production of hydrogen from steam methane reforming. Traditionally, the performance of a catalyst is defined by a combination of its activity or efficiency (its turnover frequency), its selectivity and stability (its turnover number), all of which are direct manifestations of the intrinsic physicochemical properties of the heterogeneous catalyst itself under specific working conditions. We will, of course, retain these definitions of the catalytic process, but now attempt to place discussions about a catalyst’s performance onto a new foundation by investigating the effect of improvements in the catalyst’s efficiency or performance on the resulting total energy and total CO2footprint for these prototypical fuel production and fuel conversion processes. The CSI should help the academic and industrial chemical communities, not only to highlight the current ‘best practice catalysts’, but also draw specific conclusions as to what energy and CO2emissions saving one could anticipate with higher efficiency/higher performance from heterogeneous catalysts in a particular fuel synthesis or conversion process or technology. Our aim is to place discussions about advances in the science and technology of catalysis onto a firm foundation in the context of GHG emissions. We believe that thinking about (and attempting to quantify) total energy and CO2emissions reductions associated with advances in catalysis science from a complete energy life cycle analysis perspective is extremely important. The CSI will help identify processes where the most critical advances in catalyst efficiency are needed in terms of their potential impact in the transition to a more sustainable future for fuel production and conversion technologies.

Characterization of pore coking in catalyst for thermal down-hole upgrading of heavy oil

Heavy oil and bitumen are a potential alternative energy source to conventional light crude. However, recovery of these resources can have substantial environmental impact. Downhole upgrading offers the prospect of both improving recovery, and decreasing environmental impact. However, use of catalysts to enhance downhole upgrading is limited by the need for one that can survive the extreme coking conditions arising from the cracking of heavy oil. In this work the potential of hydrogen donors to improve upgrading and enhance catalyst lifetime was considered. In order to extract detailed information on the catalyst structural evolution during reaction a novel parallel adsorption and thermoporometry characterization method was used. This technique allows detailed information to be obtained on the spatial juxtaposition of different pores, and their relative connectivity, as well as on size distributions. For catalyst operated at the conditions studied, it has been found that coking arises in smaller pores branching off the larger pores providing access to the catalyst interior. It has been found that while coking following use of different types of hydrogen donor leads to similar primary patterns of evolution in the pore-scale descriptors of the remaining accessible void-space, differences do arise in the overall accessible volume. Hence, it seems the hydrogen donor affects the location rather than general nature of the pore structure changes. However, at a secondary level of scrutiny, some differences in pore-scale evolution are also identified for different hydrogen donors. These differences identified helped the understanding of variations in the performance of different hydrogen donor and catalyst combinations.

Addition Reactions of Olefins to Asphaltene Model Compounds

Addition reactions have been proposed as a significant pathway for coke formation in the liquid-phase cracking of heavy oils and bitumens. In order to study the kinetics of olefin addition in the liquid phase, two alkyl-bridged aromatic compounds, with molecular weights of 899.70 g/mol and 1127.99 g/mol, were thermally cracked with 1-hexadecene, 1-octadecene, or trans-stilbene, in a batch microreactor at 375–430 °C for 15 to 45 min. Reaction products were analyzed by gas chromatography, high-performance liquid chromatography, matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS), and proton nuclear magnetic resonance (1H NMR) spectroscopy. Kinetic data indicate a first-order reaction in model compound concentration, with energetics consistent with a free-radical chain mechanism. Tandem MS/MS and 1H NMR spectra of the products are consistent with olefin addition through the alkyl bridge of the bridged aromatics. The results imply that (i) the addition products are able to abstract hydrog...

Kinetic study of catalytic cracking of heavy oil over an in-situ crystallized FCC catalyst

The kinetic characteristics of an in-situ crystallized FCC catalyst were reported for the first time. A six-lump kinetic model containing 24 kinetic parameters, one parameter for basic nitrogen poisoning, another parameter for aromatics adsorption and other two parameters for catalyst deactivation was established. Kinetic parameters were estimated based on experimental data at 460, 480, 500 and 520°С by fourth order Runge–Kutta algorithm and the least square method. Frequency factors and apparent activation energies were then calculated according to Arrhenius equation. The predicted data of product distribution showed good agreement with experimental data, and the relative errors were mainly within 10%. Model analysis indicated that a relative low temperature was more suitable for the production of light oil.

No.41 キュリー・ポイント・パイロライザー法を用いたゼオライト含有ミクロ-メソ多孔性複合体による重質油接触分解の解析(重質油・バイオマス・コプロセッシング(3))

No.41 キュリー・ポイント・パイロライザー法を用いたゼオライト含有ミクロ-メソ多孔性複合体による重質油接触分解の解析(重質油・バイオマス・コプロセッシング(3))

Advances of two-stage riser catalytic cracking of heavy oil for maximizing propylene yield (TMP) process.

Two-stage riser catalytic cracking of heavy oil for maximizing propylene yield (TMP) process proposed by State Key Laboratory of Heavy oil Processing, China University of Petroleum, can remarkably enhance the propylene yield and minimize the dry gas and coke yields, and obtain high-quality light oils (gasoline and diesel). It has been commercialized since 2006. Up to now, three TMP commercial units have been put into production and other four commercial units are under design and construction. The commercial data showed that taking paraffinic based Daqing (China) atmospheric residue as the feedstock, the propylene yield reached 20.31 wt%, the liquid products yield (the total yield of liquefied petroleum gas, gasoline, and diesel) was 82.66 wt%, and the total yield of dry gas and coke was 14.28 wt%. Moreover, the research octane number of gasoline could be up to 96.

Study on the Feasibility of Plasma (DBD Reactor) Cracking of Different Hydrocarbons (<inline-formula> <tex-math notation="TeX">\(n\) </tex-math></inline-formula>-Hexadecane, Lubricating Oil, and Heavy Oil)

In this paper, the cracking ability of plasma in the oil refinery, as a novel study, has been discussed. Furthermore, the cracking of n-hexadecane, lubricating oil, and heavy oil by a nonthermal plasma reactor was studied to investigate the liquid and gaseous products, gas chromatography, and simulated distillation (Sim Dis) analyzer were used. The results showed the production of hydrogen, ethane, ethylene, propane, propylene, and other hydrocarbons as a result of feedstock cracking. In these experiments, both lighter and heavier hydrocarbons were produced. In the first part, the n-hexadecane (C <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">16</sub> H <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">34</sub> ) was injected to the reactor. The production rate of hydrogen, ethylene, and propylene were 12.74, 6.91, and 2.32 sccm, respectively. In the second part, lubricating oil, containing heavier hydrocarbons (C <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">13</sub> -C <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">42</sub> ), was chosen as a feed. Plasma was able to crack this feed to C <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> -C <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">12</sub> with 39.77% (weight percent). In this part, the weight percent of C <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">17+</sub> (heavy hydrocarbons) decreased from 93.0% to 40.19%, showing that 56.8% of the heavy fraction of lubricating oil was cracked to lighter hydrocarbons. Finally, heavy oil was injected to the reactor and Sim Dis data showed that 95% of eluted materials were taken at 628°C and 459°C temperatures for raw and plasma treated heavy oils, showing 169°C difference in the distribution of the boiling point of samples. This difference was due to the presence of lighter hydrocarbons with lower boiling point.

Synergistic effect of W and P on ZSM-5 and its catalytic performance in the cracking of heavy oil

In order to develop the conversion of heavy oil with a high yield of propylene in the catalytic cracking process, ZSM-5 zeolite was modified by tungsten and phosphorus, which was proved to be an effective method. Characterization results show that the improvement of catalytic performance could be correlated to the interaction of phosphorus and tungsten species on ZSM-5. P inhibited the aggregation of tungsten species on ZSM-5 and was conductive to convert the tungsten species with octahedral coordination into tetrahedral coordination. And this ultimately led to that more acid sites were reserved after hydrothermal treatment in the tungsten and phosphorus co-modified ZSM-5 catalyst. Phosphorus species played an important role to restrain the dehydrogenation activity of tungsten. In addition, a model reflecting the interaction between tungsten species and ZSM-5 framework was proposed.

Hydrothermally stable macro-meso-microporous materials: synthesis and application in heavy oil cracking

Hydrothermally stable hierarchical materials with macro-meso-micropores were synthesized by combination of precursor assembly and PS/P123 dual templates. Precursor assembly aims at the formation of meso-micropores and improving the hydrothermal stability, and PS microspheres aim at the introduction of macropores. Moreover, worm-like mesopores vertical to the surface of PS microspheres were present, which achieve the full interconnection of macro-meso-micropores. The resulting aluminosilicates with hierarchical pores and high hydrothermal stability showed excellent catalytic cracking properties for heavy oil.

ROTATING MACHINERY FAULT DETECTION BASED ON IMPROVED ENSEMBLE EMPIRICAL MODE DECOMPOSITION

An improved EEMD approach is introduced in this paper based on automatically obtaining the adding white noise amplitude and the ensemble number according to different analyzing signal characteristics. The adding white noise affects decomposition effect is researched in detail, a criterion of adding white noise in EEMD is established, and the improved EEMD algorithm is described. Simulated signals demonstrate the effectiveness of the improved EEMD in diagnosing the faults of rotating machinery. The improved EEMD is successfully applied to an early rub-impact fault detection of machine unit for catalytic cracking of heavy oil, with the fault reason being analyzed in detail. A gear fault detection of hot strip finishing mills is also analyzed utilizing the improved EEMD method. The results show that the improved EEMD can obtain more precise diagnosis results than the original EMD and FFT spectrum.

Cracking of heavy vacuum gas oils over (HCeY) zeolite-containing, aluminum-pillared montmorillonite and activated kaolinite clays

Zeolite-containing HCeY catalysts on aluminum-pillared montmorillonites and activated kaolinites with a mesoporous structure have been tested in the cracking of heavy vacuum gas oils. The activities of the zeolite-containing and zeolite-free catalysts have been compared. The highest yields of gasoline and light cycle oil have been obtained on the Al(5.0)NaHMM + HCeY catalyst and the zeolite-free AlHKE kaolinite contact, respectively.

キュリーポイント・パイロライザーを用いたゼオライト含有ミクロ-メソ多孔性複合体による重質炭素資源の接触分解反応

キュリーポイント・パイロライザーを用いたゼオライト含有ミクロ-メソ多孔性複合体による重質炭素資源の接触分解反応

Catalytic Properties of a Hierarchical Zeolite Synthesized from a Natural Aluminosilicate Mineral without the Use of a Secondary Mesoscale Template

AbstractA hierarchical ZSM‐5 zeolite with a bimodal meso‐microporous system, high crystallinity, and a large surface area and meso‐micropore volume was successfully synthesized from a natural layered aluminosilicate mineral rectorite without using a secondary mesoscale template. The physicochemical and catalytic properties of the hierarchical ZSM‐5 zeolite were extensively characterized. The results showed that the mesopores of the synthesized hierarchical ZSM‐5, which are almost slitlike intercrystal pores, originate from the construction of primary nanorods of the ZSM‐5 zeolite. Analysis of the crystallization process revealed that the undissolved rectorite debris acted as seed crystals and played a structure‐directing role, which is the key factor that influences the formation of the hierarchical structure. Such a hierarchical ZSM‐5 zeolite, as a result of its unique structural characteristics and increased accessibility of acid sites, possessed a remarkably enhanced activity for the cracking of 1,3,5‐triisopropylbenzene, a dramatically higher anti‐deactivation ability for cumene conversion, and a significantly improved propylene‐boosting performance for heavy oil cracking than the other catalysts tested.

Kinetics of Vapor-Phase Cracking of Bitumen-Derived Heavy Gas Oil

The kinetics of vapor-phase cracking of bitumen-derived heavy gas oil and the quality of the resulting liquid products were investigated at temperatures of 600–700 °C. Light ends components were an...