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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]

Projecting future-year emission inventories in the oil and gas sector is complicated by the fact that there is a life cycle to the amount of production from individual wells and thus from well fields in aggregate. Here we present a method to account for that fact in support of regulatory policy development. This approach also has application to air quality modeling inventories by adding a second tier of refinement to the projection methodology. Currently, modeling studies account for the future decrease in emissions due to new regulations based on the year those regulations are scheduled to take effect. The addition of a year-by-year accounting of production decline provides a more accurate picture of emissions from older, uncontrolled sources. This proof of concept approach is focused solely on oil production; however, it could be used for the activity and components of natural gas production to compile a complete inventory for a given area. Implications: The Uinta Basin has unique atmospheric chemistry regimes during the winter that create ozone concentrations far exceeding those in the largest U.S. cities. This is also an area of complex regulatory authority shared among state, tribal, and federal agencies. This research accounts for regulations that are currently being implemented, and ties the effect of those regulations to emission factors used to estimate future-year inventories. This approach holds promise for future-year projections of oil and gas inventories for the region by providing a more representative life cycle of oil and gas emissions, including the disproportionate impact of older, uncontrolled sources. [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]

On June 12, 2005, at 04 h 17 min UT, the M 5.6 earthquake occurred northeast of Sakhalin Island in the vicinity of the Piltun-Astokh offshore oil-and-gas field. Oil and gas have been recovered here since 1999, and it is the strongest event in the region. All the available instrumental data have been collected to construct an objective model of the source. The contemporary seismicity of the region is analyzed on the basis of the detailed seismological observations. The obtained results are compared to the new data on the geologic-tectonic setting of the studied area. The results of the present work give ground to search for objective criteria of recognition of natural and induced seismicity in the tectonically active regions, including the region of oil-and-gas fields in the northeastern shelf of Sakhalin Island, and to reveal the physical mechanisms leading to these phenomena. [ABSTRACT FROM AUTHOR]

The article shows the results of thermal cracking of natural bitumen of Kazakhstan's two deposits. The variation of the chemical and the fractional composition of the cracking products are determined depending on the process conditions. A comparative analysis of the influence of the catalyst is carried out to composition of natural bitumen. [ABSTRACT FROM AUTHOR]

This paper presents the results of an investigation carried out on Ultra High Strength Concrete (UHSC) panels subjected to low velocity projectile impact to assess impact resistance. UHSC panel of size 350 × 350 mm and thickness 15 mm is studied under drop weight impact loading for three different pre-determined drop heights ranging from 100 mm to 300 mm. The response of UHSC panel in terms of acceleration vs time is obtained experimentally. Numerical model has been developed to simulate the impact behaviour of UHSC panel. The Brittle cracking model is used to simulate the behaviour of UHSC panel under impact loading and to perform parametric studies by varying the volume fraction of steel fibres. [ABSTRACT FROM AUTHOR]

Hydrogen assisted cracking (HAC) could lead to catastrophic failures in oil and gas industry piping and pressurized equipment with consequences ranging from heavy financial impact to fatality. Wet sour hydrocarbon services could lead to catastrophic consequences ranging from loss of lives to a heavy financial impact. This paper provides effective measures on raw plate/coil and pipes manufacturing and testing processes to eliminate susceptibility to avoid the occurrence of HAC failures including hydrogen-induced cracking (HIC), stress oriented HIC and sulfide stress cracking. These techniques include the following measures: (1) Quality control of plate/coil (raw product) manufacturing process and testing requirements, (2) quality control of pipe (finished product) manufacturing process and testing requirements, and (3) pipe selection criteria and field application quality control. Implementation of these requirements will result in enhanced oil and gas plants' safety/reliability, reduced maintenance/inspection costs, and unnecessary usage of corrosion mitigation methods, such as cladding, coating or inhibition systems. Case histories are included in this paper to illustrate the root causes of HAC. [ABSTRACT FROM AUTHOR]

A table of contents for the January 2014 issue of the journal is presented along with the authors' name index.

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 (C16H34) 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 (C13–C42), was chosen as a feed. Plasma was able to crack this feed to C4–C12 with 39.77% (weight percent). In this part, the weight percent of C17+ (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. [ABSTRACT FROM PUBLISHER]

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]

Pyrolysis of bagasse followed by nano-catalytic cracking of tar was carried out at atmospheric pressure using a dual bed micro reactor. The first bed was used for pyrolysis and the second bed was used for cracking of tar. Bimetallic 12%Ni6%Fe/γ-Al2O3 nano catalysts were prepared using microemulsion technique with water-to-surfactant ratios of 1-5. The catalysts were characterized by ICP-AES, BET, XRD, H2 chemisorption, TPR and TEM techniques and their activity and selectivity in bagasse pyrolysis were assessed. The physico-chemical properties and performance of the nano catalysts were compared with the catalyst prepared by impregnation method. The TEM images showed that small metal nanoparticles are dispersed on the surface of support in the range of 3-5nm. Using microemulsion technique with water to surfactant ratio of 1 decreased the average metal particle sizes to 3.7nm. The percentage reduction and percentage dispersion are almost doubled. A gas richer in hydrogen (15.3mol.%) and carbon monoxide (45.7mol.%) and poorer in carbon dioxide (31.6mol.%) and hydrocarbons were produced through microemulsion synthesized nano-catalysts. The proposed catalyst prepared with microemulsion (water-to-surfactant ratios of 1) increased the gas yield from 0.397 to 0.758 (m3/kg) and decreased the tar yield from 0.445 to 0.237 (g/g of biomass) compared to noncatalytic process while the heating value of the product gas remained almost constant (10-11MJ/m3). [ABSTRACT FROM AUTHOR]

The preparation of α-olefins through steam cracking of wax from coal liquefaction was studied in this paper. Compare to the 54# petroleum wax having a highest α-olefin yield per pass of 21.9%, which is the widely used feed in the commercial α-olefin plants, the α-olefin yield per pass of coal wax was increased by 10.7% at the similar reaction conditions. This paper disclosed the different reaction performances from the viewpoints of feed composition and reaction network. The effects of the cracking temperature, the residence time, and the steam ratio on the product distributions of steam cracking were investigated. The conversion per pass of coal wax was 71.0%, and the α-olefin yield per pass was 34.7% at the optimal reaction conditions, in which the cracking temperature, the residence time and the steam ratio were 660°C, 3.7 sec, and 16%. The selectivity of α-olefins was 48.9%. The productivity can be evidently improved if using coal wax as feedstocks instead of petroleum wax. [ABSTRACT FROM AUTHOR]

Main failure modes and application limit of low alloy steel oil country tubular goods (OCTG) for sour service by relevant international standard were analyzed in this paper. The influences of metallurgical and environmental factors upon sulfide stress cracking (SSC) resistance property were discussed, and selection of SSC evaluation methods were described from the point f stress analysis and fitting for service. [ABSTRACT FROM AUTHOR]

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 paper presents an application of plantwide control strategy for a complex process, like catalytic cracking process. The plantwide control strategy assists the engineer in determining how to choose the best manipulated, controlled and measured variables in the plant, when is using advanced control techniques such MPC. The result of applying plantwide control to catalytic cracking process is a hierarchical control structure, which is organized on three levels, with two advanced control techniques for the second level. From economic point of view, the development and the implementation a hierarchical control structure for the catalytic cracking process is leading to increase plant efficiency. [Copyright &y& Elsevier]

The paper focuses on investigating the impact of mineral components of Meihekou oil shale on the conversion of organic carbon from the oil shale into shale oil. A number of leaching operations were performed and each product formed in the bioleaching process was analyzed. The analysis showed that the bioleaching technology used is best for oil shale conversion. The yield of shale oil was from 8.3% to 11.2%, and approximately 8.4% of extra shale oil was obtained. During bioleaching a lot of micropores were generated in oil shale, which is favorable to transfer heat from the outside into the inside of the bioleached oil shale sample. Therefore, more shale oil could be obtained through the micropores rapidly, which may avoid shale oil from cracking into shale gas. Finally, bioleaching contributes to the production of more shale oil. [ABSTRACT FROM AUTHOR]

Pyrolysis of Bulgarian oil shale was studied by using a diamond anvil cell, which allows one to observe directly the conversion of organic matter to mobile oily liquid, solid residue and gas. This method gives the possibility to detect very precisely the temperatures of kerogen transformation during pyrolysis. It was observed that most of the gaseous products were generated later than oily liquids, most probably by cracking processes of liquid products. Due to the strong connection between mineral and organic matter, the generation of liquids and gases from oil shale occurred at higher temperature. Light intensity measurements were used to follow quantitatively the rate of reaction. [ABSTRACT FROM AUTHOR]

The effects of high pressures on the yield and kinetics of gas generated by the cracking of crude oil were investigated in laboratory simulation experiments. Samples of a low-maturity non-marine oil were recovered from the Paleogene Shahejie Formation in the Dongying depression, Bohai Bay Basin, eastern China. The oils were cracked to gas under different pressure and temperature conditions in an autoclave. Initial temperatures of 300 °C were increased to 650 °C at rates of either 30 or 100 °C/h. Reaction products were analysed at the end of each 50 °C temperature increase. Pressure conditions were either 0.1 MPa (i.e. atmospheric) or 20 MPa. Results show that high pressures inhibit or delay oil-to-gas cracking and retard the initiation of the cracking process. The temperature at which oil was cracked and the activation energy of the formation of C1-5 hydrocarbons increased under high pressure conditions, demonstrating the effects of pressure on the kinetics of the oil-to-gas cracking process. High pressures and high temperatures inhibited the conversion of C2-5 hydrocarbons to methane during secondary cracking. In addition, high pressures retarded the generation of N2, H2 and CO during cracking of oil. The presence of water increased the yields of total cracked gas, C2-5 hydrocarbons and CO2 in high-pressure conditions. The simulation results show that CO2 and C2-5 hydrocarbons have similar yields during oil-to-gas cracking. Using the kinetic parameters determined from the laboratory experiments, the yield and production rate of gas generated during the cracking of oil from Member 4 of the Paleogene Shahejie Formation in the Minfeng-Lijin sag (Dongying depression) were calculated. The results indicate that only limited volumes of natural gas in this area were derived from the cracking of oil, and that most of the gas was derived from the thermal decomposition of kerogen. [ABSTRACT FROM AUTHOR]

Purpose. Designing of criterion, which gives the opportunity to define quantitative and attribute behavior of cement stone cracking resistance. Researching of how organic and inorganic admixtures in cement composition influence on the cement stone mechanical properties. Methodology. With the help of the setting that allows controlling crack expansion, we have built graphs of the cement stone load. According to that graph we have proposed the principles of the cement stone cracking resistance factor determination. Findings. The analysis of industrial information and conducted calculations showed that risks of cement stone crack appear on the stage of construction of a well. We have defined that cement stone cracking resistance factors, previously determined by other researchers, depend on the load measured while testing. It gives no opportunity to use them for comparing evaluation of cement stone cracking resistance. With the help of modernized plant for determining of the cement stone cracking resistance we have found the work, which was spent on the cement sample damage on different stages of crack expansion. For evaluation of the cement stone ability to resist the crack expansion in the cement stone, we propose that the cracking resistance factor should be more than 1.1. To achieve this value some organic fiber should be added to the slurry. It allows us to increase the strength of the cement stone 2- 2.5 times as compared with the cement stone without additives. It has been shown that chrysotile-asbestos fiber can also be used to increase the cement stone cracking resistance when its concentration is more than 0.7%. It was shown that the cement stone without additives cannot create any cracking resistance in the zone of made crack. Originality. Proposed method of cracking resistance evaluation does not depend on experiment conditions. It has high accuracy of results and allows evaluating energetic properties of cement stone cracking. Practical value. Use of the new evaluation criterion of the cement stone cracking resistance allows us to fulfill quite accurate analysis of the reinforced cement stone resilience characteristics. [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]

In this paper, stress measurement and analysis were performed on three in-service 1500 m3 spherical petrochemical tanks to test for cracking. Welding residual stresses were measured by X-ray diffraction in both the lower girth weld and the bottom polar plate of the spherical tanks. The results show that welding residual stresses were relatively high in the lower girth weld of the #1 and #2 tanks; the maximum stress was up to 1.06 σs and occurred in the weld zone (heat affected zone or weld seam) on the inner wall. The results reveal that bulk heat treatment was ineffective for the #1 and #2 tanks but was effective for the #3 tank, because its stresses in various zones leading to surface flattening and stresses in both the lower girth weld and the bottom polar plate were less than 249 MPa (0.67 σs) and 208 MPa (0.56 σs), respectively. High welding residual stress (WRS) from poorly applied bulk heat treatment is the principal cause of spherical tank cracking. WRS in the #2 tank decreased noticeably after secondary heat treatment and repair welding were performed. [ABSTRACT FROM AUTHOR]

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]

Copyright of Obras y Proyectos is the property of Universidad Catolica de la Santisima Concepcion and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article focuses on a research which aims to develop crack growth predictions for reheat cracking using simulations of Finite Element (FE). The research highlights that Advanced Gas-Cooled Reactor (AGR) plants contain steel components which operates at a temperatures range of 500-650°C. The research further mentions that fracture mechanics specimens are required to conduct controlled laboratory tests for understanding the influence of residual stresses on crack growth behaviour.

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]

Mesopore-modified mordenite zeolitic materials with different Si/Al ratios have been prepared and tested in the biomass pyrolysis and catalytic cracking of vacuum gasoil. Alkaline treatment was carried out to generate mesoporosity. Severity of alkaline treatment was found to be of paramount importance to tune the generated mesoporosity, while it significantly affected the crystallinity of treated mordenites. It was moreover observed that the alkaline treatment selectively extracted Si decreasing the Si/Al ratio of treated samples. Catalytic activity of parent and alkaline treated mordenites was studied in the pyrolysis of biomass. All zeolitic based materials produced less amounts of bio-oil but of better quality (lowering the oxygen content from ∼40% to as much as 21%) as compared to the non-catalytic pyrolysis experiments. On the other hand, it was found that the combination of mesopore formation and high surface area after alkaline treatment of the mordenite with a high Si/Al ratio resulted in the enhancement of its catalytic activity, despite the reduction of its acidity. The increment of the decarboxylation and dehydration reactions, combined with a reduction of carbon deposition on the catalyst, resulted in a remarkable decrease in the oxygen content in the organic fraction and therefore, resulted in a superior quality liquid product. Alkaline treated mordenites were additionally acid treated targeting dealumination and removal of the extra framework debris, thus generating mesopore-modified mordenite samples with stronger acid sites and higher total acidity, as candidate catalysts for catalytic cracking of vacuum gasoil. Desilicated and especially desilicated and dealuminated mordenites exhibited the highest activity and selectivity towards LCO with the best olefinicity in gases and higher bottoms conversion. Therefore, an optimized desilicated–dealuminated mordenite additive could be an interesting candidate as a component of the FCC catalyst for a high LCO 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]

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]

Abstract: Thermal cracking of petroleum residue oil was conducted in a high-pressure batch reactor under various operating conditions, temperature in range 400–480°C, reaction time 40–100min and pressure 120–180kPa in the presence of hydrogen. Statistical design of experiment (DOE) was used to evaluate the effect of important variables in the thermal cracking of residue oil, and to obtain the optimum operating conditions. Based on the three level factorial design, quadratic model was developed to correlate the thermal cracking variables to total conversion and linear models for yields of total distillate fuels, gasoline, kerosene and diesel. From the analysis of variance (ANOVA), the most influential factor on each experimental design response was identified. The predicted conversion and yields of total distillate fuels, gasoline, kerosene and diesel were found to agree satisfactorily with the experimental values. [Copyright &y& Elsevier]

An energy-saving and environmentally friendly approach to synthesize zeolite Y from natural aluminosilicate minerals without the involvement of aluminum- and silicon-containing inorganic chemicals was developed. When used as a fluid catalytic cracking catalyst, the resulting zeolite Y exhibited an outstanding catalytic cracking performance. [ABSTRACT FROM AUTHOR]

Most research on the upgrading of bio-oil by cracking has been done under atmospheric pressure, which results in a catalyst coke yield as high as 20 wt%. In this paper, pressurized cracking, as well as co-cracking with methanol proved to be an effective solution for relieving catalyst deactivation. HZSM-5 catalyst was found to deactivate rapidly in the cracking process of pure ketones. However, when methanol was used as the co-cracking substance for ketones under 2 MPa, ketones reached a full conversion of 100 % without obvious catalyst deactivation. The highest selectivity of bio-gasoline phase from co-cracking of ketones and methanol reached a value of 31.6%, in which liquid hydrocarbons had a relative content of 97.2%. The co-cracking of hydroxypropanone and methanol had lower bio-gasoline phase selectivity but better oil phase quality (liquid hydrocarbons selectivity up to 99%) than those of cyclopentanone and methanol. Based on the experimental results, the promotion mechanism of methanol on cracking of ketones in bio-oil was illustrated by a co-cracking mechanism model. [ABSTRACT FROM AUTHOR]

Copyright of Materials Science / Medziagotyra is the property of Kaunas University of Technology, represented by Prof. Rymantas Jonas Kazys and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To maximize oil yields in the fast pyrolysis of biomass it is generally accepted that vapors need to be rapidly quenched. The influence of the heterogeneous and homogeneous vapor-phase reactions on yields and oil composition were studied using a fluidized-bed reactor. Even high concentrations of mineral low char (till 55 vol %) appeared not to be catalytically active. However, the presence of minerals, either in biomass or added, does influence the yields, especially by the occurrence of vapor-phase charring/polymerization reactions. Contradictory, in the absence of minerals, homogeneous vapor-phase cracking reactions were dominant over polymerization/charring reactions (400-550°C, 1-15 s). With increasing vapor residence time, the oil yield reached an asymptotic value, which decreased with temperature. At a vapor temperature of 400°C no decrease in oil yield was observed, but dedicated analysis showed that homogeneous vapor to vapor reactions had occurred. © 2011 American Institute of Chemical Engineers AIChE J, 2012 [ABSTRACT FROM AUTHOR]

Peridynamic (PD) theory is used to investigate the dynamic responses of electronic packages subjected to impact loading arising from drop-shock. The capability of the PD theory to predict failure is demonstrated by simulating a drop test experiment of a laboratory-type package. The failure predictions and observations are exceptionally similar. For the drop test simulation of a production-type package, the finite element method (FEM) and PD theory are coupled via a submodeling approach. The global modeling is performed using the FEM while the PD theory is employed for the submodeling and failure prediction. The analysis yielded the outermost solder joint as the critical joint, with failure at the interface between the solder and copper pad on the printed circuit board side. [ABSTRACT FROM AUTHOR]

We have performed a direct comparison of n-hexane cracking catalysed by a zeolite (H-ZSM-5) and a heteropoly acid (phosphotungstic acid, HPW). This comparison was examined by employing density functional theory, including dispersion energy, M06-L, for the purpose of understanding these two catalysts for this industrially important reaction. The predicted adsorption energies of hexane are −21.4 and −6.8 kcal/mol for H-ZSM-5 and HPW, respectively. The protolytic cracking mechanism is proposed to proceed via the first step of the C-C activation and is found to be the rate-determining step with activation energies of 42.8 and 41.4 kcal/mol for H-ZSM-5 and HPW, respectively. We also discuss the advantages and disadvantages of both catalysts for hydrocarbon cracking and give a perspective of utilising cutting-edge molecular design for a tailor-made hybrid catalyst. © 2011 Canadian Society for Chemical Engineering [ABSTRACT FROM AUTHOR]

The second largest source of propylene supplied for petrochemical application is from fluid catalytic cracking (FCC) units. The primary function of the FCC unit has typically been to produce gasoline. However, refiners have been taking advantage of opportunity to produce and recover more propylene from their FCC unit by increasing reaction severity via riser temperature, adding shape selective catalyst, and installing a propylene recovery unit (PRU). At a conventional FCC process propylene exists in the off gas of FCC and it is about 6 wt% of off gas by changing the FCC process parameter quantity of propylene in off gas can be more than 20 wt% by using ZSM-5 additives and increasing temperature The effects of operating parameters, such as reaction temperature, and ZSM-5 as FCC catalyst additive, on the distribution of the product and the yield of propylene were investigated on a bench-scale fluidized bed reactor. It is the aim of this work to perform an overall analysis of the yields and selectivity of hydrocarbons obtained in the vacuum gas-oil conversion over FCC and ZSM-5 catalysts. The effectiveness of ZSM-5 additive in the FCC process was investigated by doing experimental work in a bench-scale setup. The experiment data of off gas analysis showed that vacuum gas oil cracking at high reaction temperatures of 450–550°C increases the yield of propylene. Similar behavior is observed with the addition of 10–25 wt% ZSM-5 additive. The combination of the two effects (high temperature and ZSM-5 addition) makes the FCC unit an excellent source of light olefins for downstream petrochemical units. Higher FCC reactor temperatures (600–650°C) would not have positive effects for increasing propylene yield. [ABSTRACT FROM PUBLISHER]