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Coker kero stream is obtained from delayed coking which contains saturates with alpha olefins and PNA compounds which was physicochemical characterised. The fractions present in coker kero may be used further for value added products such as alkyl benzene and naphthalene etc. The study described potential of coker kero via aromatics and non-aromatics separation by using liquid-liquid extraction (LLE) with N-methyl pyrrolidone (NMP), acetonitrile and methanol as solvents of different polarity. Methanol imparts best colour improvement as per ASTM D-1500. Beside this, adsorption study on coker kero was performed using fuller’s earth, chalk powder, red ochre and wood-stick’s ash as adsorbents. The adsorption study suggested that fuller’s earth not only separate aromatics and non-aromatics form coker kero, but also acts as a better adsorbent than graphitic carbon (activated charcoal) and is found suitable for colour improvement comparatively. This study inferred the separation of polar components, improvement in the colour, odour and established the stable fuel. FT-IR study suggested that N-methyl Pyrrolidone gives better results comparatively other solvents. HC22 type analysis of coker kero raffinate and extract phase confirm the sharp extraction of coker kero feed using N-Methyl pyrrolidone as it is a good solvent for extraction of aromatics. GCMS and HRMS compositional analysis successfully performed for the coker kero and it is separated aromatic and non-aromatic fractions.

The organosulfur compounds of mixed raw materials—vacuum gas oil in a mixture with heavy coking gas oil reactions group kinetic were investigated during hydrotreating at a hydrogen pressure of 5 MPa at various temperatures (360, 390, 420 °C) and LHSV of 0.5, 1.0, 2.0 and 4.0 h−1 in the presence of Ni6–MonW12-n/γ-Al2O3 sulfide catalysts, prepared on the base of phosphoromolybdenum and phosphorotungstenheteropolyacids. The total sulfur content was determined in feed and hydrogenates. A kinetic model describes the process of hydrodesulfurization of vacuum gas oil in hydrotreating on Ni6–MonW12-n/γ-Al2O3 catalysts based on phosphomolybdenum and phosphotungsten heteropolyacides (HPAs) has been selected. The adequacy of the kinetic model of the 2nd order was verified by means of the coefficient of determination and based on the values of the Fisher criterion. The optimal modes of the vacuum distillate hydrotreating process may be selected on the base of obtained data on the kinetics of hydrodesulfurization (HDS) reactions. The kinetic characteristics of the HDS and hydrodearomatization (HDA) reactions of the mixed feed compounds on Ni6–MonW12-n/γ-Al2O3 catalysts based on phosphor–molybdenum and phosphotungsten HPA were determined with the usage of chosen model. The Ni6PMo12/γ-Al2O3 catalyst was most active one in the HDS reaction. The activity of catalyst samples in hydrogenation reactions was investigated. It was shown that the most active sample is Ni6PMo4W8/γ-Al2O3.

Elemental sulfur is used to cross-link heavy coker gas oil (HKGO) with only 0.44 wt% olefinic hydrogen content in the absence of solvent; subsequent pyrolysis yields sulfur-doped porous carbon with Brunauer–Emmett–Tell (BET) surface area (s.a.) around 1714–1785 m2 g−1. The heavy coker gas oil does not need demetallation or hydrotreating to enable this. The usual problems (residue metal and sulfur/nitrogen) in HKGO became an opportunity in product carbon to anchor CO2 resulting in high sorption capacity.

A natural hydrogen donor, i.e., a subfraction of the coker gas oil, was used in thermal upgrading of the Venezuela extra-heavy oil. The role of hydrogen donor was quantitatively studied by a combin...

This paper presents the results of testing a catalyst system developed for the demetallization and desulfurization of vacuum gas oil and heavy coker gas oil mixture at a pressure of 6 MPa, a temperature of 360-370°C, and a feed volumetric rate of 1 h-1 for obtaining a product having a sulfur content of 0.05 wt.%. The composition of RMB 30 marine fuel is developed with the application of a distillate fraction obtained from secondary processes and a depressant-dispersant additive in order to bring the pour point to the requirements of GOST32510-2013.

Demetallization of a mixture of vacuum gas oil with heavy coker gas oil on CoMo/γ-Al2O3 catalysts with different pore structures was studied, and the influence of the catalyst pore structure on the process results was demonstrated. For the demetallization catalysts to be effective, their pore size should be restricted not only from below but also from above. When using samples with broad pores, effects of the hydrodesulfurization and hydrodemetallization inhibition can arise owing to adsorption of supramolecular structures of heavy residues, in particular, of asphaltenes.

Behavior of the CoMo/Al2O3 catalyst was experimentally studied in the course of hydrotreating of a straight-run gas oil with high content of sulfur (>2 wt %) and its mixture (up to 30 wt %) with light coker gas oil in the temperature range 335–365°C and liquid hour space velocity of feedstock deliver of 0.8–2.5 h−1. It was shown that addition of gas oil to the straight-run gas oil in hydrotreating under the conditions corresponding to the working conditions of the existing domestic hydrotreating installations [L-24-5, L-24-6, L(Ch)-24-7] has oppositely directed effects, depending on temperature and feedstock delivery rate. For example, the additives lead in the temperature range 335–350°C to an increase in the content of sulfur in hydrotreating products. At a temperature of 365°C, better sulfur-related parameters are reached in processing of feedstocks containing light coker gas oil. The observed dependences are accounted for as follows: the dilution of the straight-run gas oil by addition of light coker gas oil leads to a decrease in the content of difficulty converted sulfur-containing compounds, but makes larger the content of nitrogen-containing compounds inhibitors of the hydrodesulfurization reaction, the influence of which on the reaction rate becomes weaker with increasing temperature.

Two NiMo sulfide catalysts, supported on Al2O3 and silica–alumina, respectively, were compared in the hydrotreatment of a mixture of straight-run and coker gas oil. Experiments were conducted in a ...

To convert Light cycle oil (LCO) with low hydrogen content into more light fraction such as low-carbon olefins and gasoline during the catalytic cracking reaction, it is necessary to replen...

The search applied the evaluation and risk assessment of H2S gas at Suez Oil Processing Company (Coker complex units). Different samples were measured for the Hazard H2S in many places around the Coker units in 2012. TiO2 was prepared by hydrothermal approach in presence of oleic acid. TiO2 was characterized by XRD and SEM. Treatment of the produced H2S was carried out by photocatalysis using (TiO2) phcatalyst and UV light source. The removing efficiency of H2S reaches 98% using UV lamp. The stability and the capacity of the removing were also studied. The degradation reaches 97% 96% after catalyst poisoning through three cycles.

The coking behavior of serial petroleum residues derived from deep-vacuum distillation of Venezuela extra-heavy oil has been systematically investigated in laboratory-scale coking appliances from the perspectives of distribution and properties of coking products. The usage of residue with deeper distilling cut would favor the decreasing of low-value products, i.e., coke and coking gas. The hydrogen circumstance of coking feedstock indicated by 1H NMR analysis, implies residue with ultra-deep distilling cut as a valid hydrogen evolution potential. By comparison with the de-metallization rate in the hydrodemetallization process (Ni, 61.2%; V, 80.8%) (Zhang et al., 2006), the performance in the study seems more promising. Evidently, the stripping of VGO would notably change the morphological characteristics of resultant coke. However, no secondary assembled or clustered shot coke was observed in the coker, which made the decoking quite easy. A valid linear agreement between the area of green region quantitatively assessing the process flexibility and the metal content has been established. The extrapolation (dot line) of the trend suggests that shot coke formation cannot be avoided in any circumstance of the study if the metal content of coking feedstock is over 1516 μg g−1.

Delayed coking is one of the most widely used residue upgradation process in crude oil refining where vacuum residue is thermally cracked and converted into distillates and petroleum coke. During heating of vacuum residue in coker furnace, coke is continuously deposited in furnace tubes which is removed at regular intervals by one of the three methods namely (i) pigging, (ii) steam air decoking or (iii) online spalling (OLS). OLS is one of the preferred methods of coke removal from coker furnace tubes. We have noticed very effective as well as “not so effective” OLS in a commercial delayed coker furnace. In present article, the changes in composition and properties of furnace coke during effective and ineffective OLS were systematically analyzed by various analytical tools such as Dilatometer, TGA, HRSEM, SEM-EDX and XRD. Based on these analyses, it was found that inorganic deposits such as iron sulphides and tube metal corrosion products play a major role in failure of OLS. Higher total acid number (TAN) of vacuum residue may be promoting the formation of iron sulfide deposits in furnace tube.

Inferior coker gas oil (ICGO) derived from Venezuelan vacuum residue delayed coking is difficult to process using fluid catalytic cracking (FCC) or hydrocracking (HDC). The high content of nitrogen and condensed aromatics leads to major coking and readily deactivates the acid catalyst. In this work, a sequence of hydrotreating (HDT) and FCC processing is used to effectively convert ICGO to a high-value light oil product. The results show a higher overall conversion and a significant increase in the yield of gasoline compared to FCC processing. Molecular level characterization of the nitrogen compounds and condensed aromatics before and after HDT confirms that the nitrogen content and the 2+-ring aromatic content decreased, whereas the single-ring aromatics increased. The nitrogen compounds were mainly N1, N1O1, N1O2, and N1S1 class species in basic nitrogen and N1, N1O1, N1O2, N2, and N2O1 class species in non-basic nitrogen. Moreover, the double bond equivalent of these species shifted to lower values. T...

The influence of the introduction of V2O5 into NiMo/Al2O3 catalysts on their activity in hydrodesulfurization (HDS) and hydrogenation reactions of the components of petroleum fractions has been studied. The activity of the synthesized catalysts has been determined in the straight-run diesel and light coker gas oil hydrotreating processes in a flow-through unit under hydrogen pressure. The most active catalyst for HDS and hydrogenation of polycyclic aromatic hydrocarbons has been synthesized using VMo12 heteropoly compounds: the activity increases by 6–10 and 11–13 wt % in HDS and PAH hydrogenation, respectively, at different temperatures. It has been shown that the activity of the regenerated catalyst further impregnated with the vanadium compound in HDS and PAH hydrogenation increases by 2–5 rel. %, as compared to the regenerated catalyst.

Naphtha reforming processes are widely used for high-octane gasoline production. These processes require high reaction temperature and high pressure of expensive hydrogen. Also, olefins and aromatics are produced for achieving high octane number, which could cause severe environmental issues. Here, we report a novel method of non-thermal plasma assisted catalytic reforming of naphtha at near ambient conditions. Conventionally used hydrogen has been replaced by cheaper methane in this study. Non-thermal plasma could effectively convert methane and naphtha to high-quality fuel at near room temperature and atmospheric pressure. A high-quality fuel with high content of iso-paraffin and low content of olefin and aromatic is produced over optimized Ga/mix-ZSM-5 with non-thermal plasma applied. The produced liquid product has a notably higher iso-paraffin content (increased from 21.5%–40.5%) than raw naphtha while the coke deposition (17.4 %) and the content of olefins (decreased from 13.5%–7.8%) and aromatics (dropped from 18.1%–5.9%) are well controlled. The partial desulfurization of fed coker naphtha by close to 60 % is also successfully achieved. A systematic model compounds study is conducted to investigate the involved mechanism of non-thermal plasma assisted catalytic naphtha reforming and coke deposition. Based on the studies of C6-C16 model compounds (including paraffins, olefins, dienes, cyclo-paraffins, cyclo-olefins and aromatics), a hypothetic reaction mechanism is proposed. A series of control experiments is also carried out to reveal the synergistic effect between non-thermal plasma, catalyst, and methane participation. This research thus pioneers a cost-effective and environmental-friendly route for naphtha reforming at mild conditions.

Activated carbon injection has been proven to be an effective control technology of mercury emission from coal-fired power plants. Petroleum coke is a waste by-product of petroleum refining with large quantities readily available around the world. Due to its high inherent sulfur content, petroleum coke is an attractive raw material for developing mercury capture sorbent, converting a waste material to a value-added product of important environmental applications. In this study, petroleum coke was brominated by chemical-mechanical bromination. The brominated petroleum coke was characterized for thermal stability, mercury capture capacity, and potential mercury and bromine leaching hazards. Bromine loaded on the petroleum coke was found to be stable up to 200°C. Even after treating the brominated petroleum coke for 30min at 600°C, 1/3 bromine remained on the solid. The sorbent from bromination of sulfur-containing petroleum coke was shown to be a promising alternative to commercial brominated activated carbon for capture of elemental mercury from coal combustion flue gases.

Two narrow fractions distilled from Liaohe coker gas oil were used for the research. The distribution of basic nitrogen compounds in feedstocks and their liquid products were characterized by ESI FT-ICR MS. The results showed that N1 class species were the most predominant in both feedstocks and products. The catalytic cracking progress reduced the relative abundance of all class species, except for the N1 and N1S1 class species. Although the N1 class species had longer side chains and higher condensation in the heavier feedstock, the distribution of N1 class species became similar in the two liquid products.

Multi-lump kinetic models for model compounds representative of various sulfur (S) and nitrogen (N) compounds in coker gas oil (CGO) were developed to describe CGO hydrodesulfurization (HDS) and hydrodenitrogenation (HDN) processes, respectively. Model parameters were obtained from fitting of operating data. Validation results revealed that models could predict contents of S and N in products accurately, and hydrogen consumption of HDS and HDN can be estimated. The effects of the temperature, hydrogen/oil ratio, and pressure on the reaction performance were also investigated.

Refineries process a number of gas oils such as straight run gas oil (SRGO), light cycle gas oil, coker gas oil and visbreaker gas oil for producing a common gas oil pool to be used as a transportation fuel. Considering stringent sulfur standards, new strategies and design modifications are being evaluated for desulfurization of these gas oils with minimum loss of oil during the desulfurization process. In this review, developments in solvent extractive desulfurization of gas oil have been discussed from both fundamental and applied point of views. Various performance indicators used for solvent evaluation/screening in computational and experimental studies are discussed. Particular emphasis has been given on latest developments in performance evaluation of organic and ionic liquid solvents for desulfurization of SRGO and other gas oils. Various possible designs of solvent recovery section to remove solvent from raffinate and extract phases for solvent recycling have been reviewed. Various potential optio...

The objective of the present study is to develop a better hydrodesulfurization (HDS) kinetic model on the basis of a fundamental and comprehensive understanding of the different HDS reactivities of various sulfur compounds in middle distillates and the inhibition effects of the coexisting nitrogen and aromatic compounds. Five middle distillates blended from straight run gas oil, heavy gas oil, and coker gas oil were hydrodesulfurized over a commercial catalyst at 300 °C, 4.0 MPa H2 pressure, a H2/oil volume ratio of 200, and different liquid hourly space velocities. Identification and quantification of sulfur compounds in the feedstocks and their hydrodesulfurized products were conducted by using GC-PFPD to classify the sulfur compounds into four groups according to their molecular structures and reactivities. It was found that the HDS of each sulfur group follows pseudo-first-order kinetics. Correlation of the obtained first-order rate constants with both the nitrogen concentration and the feedstock dens...

Crude distillation is one of the first and most critical steps of the petroleum refining process. It separates crude oil, a complex mixture of many different hydrocarbon compounds, into fractions based on the boiling points of the hydrocarbons. Characteristic boiling points of crude oil components range from 32°C to over 427°C. In this study, four units of gasoline production were added (Isomerization, Alkylation, Fluidized-Bed Catalytic Cracking (FCC) and Delay coker), Beside that, Reformate unit is exist in the refinery. However, the basis for the crude assay for ALZAWIA refinery which contained two different crudes - ALHAMADA and SHRARA - is 60,000 bbl/day (7,500 Ton/day). As the result of gasoline which produced from isomerization unit is 16,734 Kg/hr, Reforming unit is 84,823 Kg/hr, Fluidized-Bed Catalytic Cracking (FCC) is 71,418 Kg/hr, Alkylation unit is 32,356 Kg/hr and Delay Coker is 12,000 Kg/hr.

Today, many European refineries finish up with excess of low-quality thermal naphthas that are hard to be marketed and, commonly, end being absorbed by catalytic naphthas at the expense of their higher quality. In this context, we propose to investigate the suitability of co-feeding thermal naphthas, i.e. visbreaker and heavy coker naphtha, with vacuum gasoil (VGO) to the fluid catalytic cracking unit. A riser simulator reactor has been used in the experimentation and tested conditions have been: 500 and 550 °C; C/O mass ratio, 6 gcat goil−1; and, residence time, 3 − 12 s. Products have been lumped according to the fractionation made in refineries in: dry gas, liquefied petroleum gases, gasoline, light cycle oil and coke. The results reveal that the co-feeding of any of the naphthas hinders the over-cracking increasing the contents of gasoline and that it inhibits the condensation reactions that produce coke. Two main factors contribute to these results: (i) the competitive adsorption and reaction between the components of the naphthas and the VGO; and (ii) the shortening of the residence time caused by an increase of the flow when the naphtha is co-fed. It should be highlighted the variation in the composition of the gasoline produced with the blends, with overall reductions of the contents of olefins and aromatics.

The upgrading of heavy coker naphtha under conditions of the industrial fluid catalytic cracking (FCC) unit has been investigated, with the aim of obtaining light olefins and a gasoline fraction suitable to be used in the blending of motor fuels. The experiments have been conducted in a riser simulator reactor at: 500 and 550 °C; catalyst to oil mass ratio, 6 gcat goil−1; and, contact time, 3 to 12 s. Moreover, the effect of the properties of two commercial equilibrium catalysts on the products has been also assessed. Products have been grouped in: dry gas, liquefied petroleum gases, gasoline, light cycle oil and coke. The presence of strong acid sites in the catalyst favors the formation of light olefins, yielding a 5 and 3.3 wt% of propylene and butenes, respectively, at 550 °C and 6 s. A higher content of zeolite (with moderate acid strength sites) and a bigger size of the mesopores of the matrix promote the formation of a commercially interesting gasoline fraction with a yield of 90 wt% under the same conditions, with a concentration of aromatics, naphthenes, n-paraffins, olefins and iso-paraffins of 25, 10, 28, 21 and 15 wt%, respectively, and a RON of 84.

Integration of solvent deasphalting and asphaltenes gasification has been reported as a convenient alternative to coker based upgrading of bitumen, derived from oil sands. However, very limited work has been carried out on pyrolysis and gasification of asphaltenes at entrained flow conditions. The present study aims at addressing this gap, and provides a better understanding of the major intermediate in gasification process – char. Chars were prepared at different operating conditions in an atmospheric entrained flow reactor. Extensive characterization techniques were used to identify the changes in morphology, structure and composition of chars. We estimated the global gasification reactivity of chars with steam and CO2. Chars exhibited an internally hollow structure with porous walls. The nominal size of individual char particles and degree of fragmentation were greatly influenced by the operating conditions. H/C ratio, aromaticity and macro-porosity of chars increased with an increase in operating temperature, while content of heteroatoms and global reactivity showed a gradual decrease. Increase in residence time had marginal effect on char composition, morphology and global reactivity. V and Ni tend to accumulate in chars; however, their effect on global reactivity could not be established.

In the present study, removal of sulfur and aromatic compounds from straight-run gas oil (SRGO), light cycle oil (LCO), coker gas oil (CGO), and their mixture, termed as mixed gas oil (MGO), was studied using N-methyl-2-pyrrolidone (NMP) solvent in a single-stage batch extractor and continuous countercurrent packed-bed extraction column. The effect of the extraction temperature (TE), solvent/feed ratio (S/F), and antisolvent concentration (Wc) on the degree of sulfur removal (Dsr), yield of extracted gas oil (Y%), and performance factor (Pf,α), which combines both Dsr and yield, was studied in a single-stage batch extractor. After optimization of the operating conditions for SRGO, LCO, and CGO in a single-stage batch extractor, studies on MGO were carried out in both a single-stage batch extractor and continuous countercurrent packed bed at estimated optimized values of TE, S/F, and Wc. Issues related to the loss of valuable hydrocarbons with extract and value addition to extract hydrocarbon have been add...

The conjugated dienes if present in gasoline have the tendency to polymerize and cause fouling during various refinery processes. Therefore the conjugated dienes need to be reduced. While the conjugated dienes in gasoline are undesirable, the olefins are desirable and act as octane booster. The selective hydrogenation unit selectively reduces conjugated dienes keeping the content of olefins more or less intact. A method based on HPLC-UV-RI has been reported to simultaneously monitor the conjugated dienes and olefins content in the gasoline range samples. The reported method has the detection level of 0.02 (w/W)% for the total conjugated dienes with respect to 2,4-dimethyl 1,3-pentadiene (DMP). The calibration curve for DMP is drawn in the range 0.2–2.5% (w/W) and the R2 is found to be 0.9972. The method is also applicable for the estimation of olefins content above 10% (w/W) level with respect to 1-octene. The calibration curve is drawn in the range 10–50% (w/W) of 1-octene and the R2 is found to be 0.9995.

This communication highlights the possibility of using a novel two-stage process for the co-upgrading of natural gas and petroleum coke into liquid hydrocarbons. The first stage consists of the catalytic dehydroaromatization of methane characterized by producing hydrogen and aromatics: benzene, naphtalene, toluene, etc. The non-reacted methane plus hydrogen and aromatics produced in the first stage are directed to the second stage to react with the petroleum coke. Basic engineering analysis of proposed two-stage process suggests light petroleum production of 160,000 bbl/day from 20,000 ton/day of petroleum coke actually by-produced from Venezuelan Orinoco’s heavy oil belt. Residual coke should be volatiles free therefore useful as a calcined coke.

The objective of this work is to investigate the production possibility of high octane environmental ethanol gasoline blends based on Euro specifications. The environmental gasoline is the key element to keep the environment safe and clean. Moreover, it reduces gas emissions after combustion of gasoline. One of the main methods to produce the environmental gasoline is blending gasoline with oxygenated compounds such as ethanol. Ethanol is chosen among other oxygenated compounds as it has a high influence on physico-chemical characteristics of gasoline rather than other oxygenated compounds. In addition, it has a high octane number as well as it is not polluting the environment and clean additive. In the experimental study, the choice of environmental gasolines are based on Euro- 3 specifications for samples without ethanol blend and Euro-5 specifications for samples with ethanol blend; after upgrading. Various blend stocks have been prepared which have reformate, isomerate, full refinery naphtha (FRN), heavy straight run naphtha (HSRN), hydrocracked naphtha, heavy hydrocracked naphtha, coker naphtha and heavy coker naphtha. In this study, ASTM standard methods are performed for spark ignition fuels to characterize its physical and chemical properties. The results show that one has exhibited the optimum specifications of Euro-3 and thus its physico-chemical characteristics are 755.11 Kg/m3 of density, 55.88 of °API and 95 of RON, 88 of MON, 40% by volume of aromatic content and 0.66% by volume of benzene content. Moreover, ASTM distillation curve shows that the volume percentage at 150°C is 83. At the same time, the final boiling point (FBP) and recovery volume percent are 198°C is 96% respectively. While another sample has the poorest physical as well as chemical properties so that it is blended with ethanol to upgrade its characteristics. Therefore, the target is determining the optimum ethanol volume percent to be blended with poorest sample to yield the highest properties of gasoline. These blends are namely as E0, E5, E10, E15, E20. The results indicate that E5 is the optimum one for Euro-5 specifications after upgrading and thus its physico-chemical characteristics are 745.55 Kg/m3 of density, 58 of oAPI, 101 of RON, 98 of MON, 32.65% by volume of aromatic content and 0.47% by volume of benzene content. Moreover, ASTM distillation curve illustrates that the volume percentage at 150°C is 75. At the same time, the final boiling point (FBP) and recovery volume percent are 190°C and 97% respectively. In addition, its Reid vapor pressure equals 8.1 psi and the heat of combustion equals 35 MJ/L. In the final, Blending gasoline with ethanol is an essential issue concerning the production of environmental gasolines.

In the hydroprocessing of coker naphtha (hydrodesulfuration and hydrodenitrogenation), silica poisoning of hydrotreating catalysts represents a severe problem due to the deposition of Si species, which deactivate the catalyst and shorten its life time. The deactivation results of the sulfided NiMo/γ-Al 2 O 3 hydrotreating catalyst, obtained by running a long-term test, are presented. Refinery coker naphtha was processed in a continuous hydroprocessing unit in a mini-scale laboratory under industrial conditions. Catalyst samples from 15 to 90 days on stream were characterized. Si determination and the evolution of the structural characteristics of these samples were followed by 29 Si MAS NMR, FTIR, textural analysis and scanning electron microscopy (SEM) performing microanalysis by dispersion energies (EDS). 29 Si MAS NMR results confirmed the deposition and evolution of different Si species on the catalyst surface with the time on stream. The increasing content of Si species in the catalyst affected textural properties such as surface area and pore volume by decreasing them; as for the chemical properties, the Bronsted/Lewis (B/L) ratio was modified without increasing the coke formation and cracking activity. From the coker naphtha hydrotreating processes, only the hydrodenitrogenation activity was affected. The Si deposition profile shows that the concentrations were higher in the external than in the internal surface of the pellets. The shape of these profiles indicates that the deposition process becomes diffusion rate limited.

Alkali desulfurization of petroleum coke is an important technology, can improve the performance of the final products of petroleum coke, while reducing air pollution. This paper studied the conditions for desulfurization of calcined petroleum coke using NaOH solid powders. The experimental results show that, the grain size in the range of experiment did not seem to influence desulphurization. With the increase of temperature, adding alkali coke ratio, reaction time, desulfurization of petroleum coke rate increased. In the alkali coke ratio of 2, the reaction temperature is 500°C, the reaction time is 2 h, the desulfurization of petroleum coke ratio reached 98.1%. Desulfurization of petroleum coke rate by prolonging the reaction time, to a certain extent, maintains the same level of lowing alkali coke ratio.

Low thermo-oxidative stability of Mahwa oil as frying-oil or industrial lubricant is of great concern. It can be improved by the help of suitable antioxidant. The present antioxidants were developed for petroleum products and majority of these are not suitable for vegetable oil. In future, new type of anti-oxidant preferably non-toxic and eco-friendly will be needed to meet new ecological and performance requirements. This paper presents a systematic approach to identify suitable antioxidant for Mahwa oil and its derivatives. Synthesized and procured compounds were evaluated as anti-oxidant to know their effectiveness in Mahwa oil. Rotary bomb oxidation test, universal oxidation test and panel coker test methods were adopted for this study. The thermo-oxidative stability of Mahwa oil was increased significantly by using some eco-friendly additives. The results indicate that N-alkyl piperazine, anisole, benzoate and citrate are very effective at 200 g/l dose.

To investigate the effects of operating conditions and the catalyst activity on the transfer regularity of sulfur and nitrogen during the cracking process of coker gas oil (CGO), the CGO was cataly...

The fluid catalytic cracking (FCC) performances of three typical coker gas oil (CGO) in China were investigated in a fixed fluidized-bed reactor. Effects of the blending ratio of CGO to vacuum gas oil (VGO), comparative FCC performances of different CGOs, and effects of operating conditions on CGO catalytic cracking performance were discussed. Based on these, the competitive adsorption effects on CGO catalytic cracking were analyzed. The results show that the conversion decreases with the increasing blending ratio of CGO to VGO due to lower reactivity of coker gas oils. The catalyst to oil ratio (CTO) has a larger influence on CGO catalytic cracking performance than the reaction temperature and weight hourly space velocity (WHSV) has. A competitive reaction area and a free reaction area can be distinguished based on the relation of CTO and CGO catalytic cracking performance.

Coker gas oil (CGO) is difficult to be cracked in the conventional FCC process, due to their high nitrogen content, especially the basic nitrogen compounds. To enhance the conversion of CGO, the high reaction temperature and catalyst to oil ratio processing scheme was performed in a pilot-scale riser FCC apparatus. To study the impact of (basic) nitrogen content, two kinds of CGO were tested. The results show that increasing the reaction temperature and CTO is an effective method for enhancing the conversion of CGO. The (basic) nitrogen content significantly influences the cracking behavior of CGO and the choose of optimal reaction conditions.

In collaboration with Total E&P Canada (TEPCA), CanmetENERGY conducted an extensive research program to investigate possible alternatives for TSRU tailings disposal. We have reported on alternative methods for TSRU tailings disposal without recovery of asphaltenes in an earlier publication.[1] Because the asphaltenes are high-molecular-weight hydrocarbons and may have potential for use as fuel or paving material, in this work, we investigate possible approaches for recovery of the asphaltenes from TSRU tailings. Two methods were tested, solvent extraction and aggregation. In the first method aromatic solvent is mixed with TSRU tailings to dissolve the asphaltenes followed by centrifugation to remove mineral solids and water. The experimental results demonstrated that more than 90% of the asphaltenes in the tailings can be recovered from the tailings. The recovered asphaltenes contained only a small fraction of mineral solids and may be useable as coker feed. In the second method, TSRU tailings are agitated at elevated temperature (80°C) at which the asphaltene particles form large aggregates and separate from the tailings, giving an asphaltene-rich phase and almost asphaltene-free tailings. The recovered asphaltene aggregates still contain significant amounts of mineral solids and water, and would require further treatment. Several coking tests were conducted using the recovered asphaltenes and the asphaltene aggregates. The results demonstrated that about 40 wt% of the recovered asphaltenes can be converted to lighter oil fractions under the coking conditions used in this work.

We have investigated and established a preparative method of using a solid-phase extraction cartridge containing Ag+-exchange resin (Ag+-SPE) for separating olefins and paraffins in the saturate fractions of coal tar and petroleum coker oil. The successful separation of paraffins and olefins was confirmed by gas chromatography coupled with mass spectrometry (GC–MS). Proton nuclear magnetic resonance (1H NMR) spectroscopy was applied to determine the olefin structures for olefin-type distributions. None or negligible amounts of iso-α-olefins were detected by 1H NMR in the coal tar but were found significant in the coker oil. Gas chromatography coupled field ionization time-of-flight mass spectrometry (GC–FI-TOF MS) was employed to determine the molecular distribution of paraffins and olefins. With separate paraffin and olefin fractions, the differentiation between isomers, such as monocycloparaffins versus monoolefins, can be made.

An explosion in an atmospheric storage tank initiated additional tank explosions and a pool fire at a tank facility in Norway. The tank farm had been operated as a purification plant for a petroleum product called coker gasoline. The process entailed extraction of malodorous sulfur containing components, in particular thiols (mercaptans). After several tanker loads of coker gasoline had been treated with a solution of sodium hydroxide and water, the efficiency of the sweetening process declined as precipitated waste accumulated in the tanks and the alkaline solution became increasingly saturated with impurities. The approach adopted for handling the accumulated waste included the addition of hydrochloric acid to neutralize the spent caustic. The explosion occurred when about 80% of the scheduled amount of acid had been added to the solution in the tank. There were no fatalities in the accident, but at least two people received medical treatment for injuries sustained during the course of events. The investigation concluded that the accident was caused by a chemical explosion in the tank. Several factors point toward thiols as the predominant constituents in the fuel–air mixture, but vapors from other volatile substances may also have played a decisive role. The ignition source was most likely a hot surface, resulting from adsorption of volatile organic compounds on activated carbon in the air filter and subsequent self-heating and glowing combustion in the carbon bed. The article summarizes the main results from the accident investigation and lists various measures that can be taken to prevent similar accidents in the future. © 2013 American Institute of Chemical Engineers Process Saf Prog 32: 268–276, 2013

Coker gas oil (CGO) is a poor-quality feed- stock for fluidized bed catalytic cracking (FCC) or hydrocracking. The pretreatment of CGO, especially hydrotreating, can significantly improve the product quality and protect the catalyst. In this work, we studied the hydrodesulfurization (HDS) of CGO in a slurry reactor. All the experiments were carried out in an autoclave using a NiMo/Al2O3 catalyst at reaction temperature 340°C- 400°C, pressure 6-10 MPa, and stirring speed 800 r$min -1 , with hydrogen-to-oil ratio in the range of 500-1500. The effects of the operating parameters on the desulfurization ratio were investigated and discussed. A macro reaction kinetic model was established for the HDS of CGO in the slurry reactor.

Fast pyrolysis of biomass can be used to produce a raw bio-oil product, which can be upgraded by catalytic hydroprocessing to hydrocarbon liquid products. In this study, the upgraded products were distilled to recover light naphtha and oils and to produce a distillation residue with useful properties for coker processing and production of a renewable low-sulfur electrode carbon. For this hydroprocessing work, phase separation of the bio-oil was applied as a preparatory step to concentrate the heavier, more phenolic components, thus, generating a more amenable feedstock for residue production. Low residual oxygen content products were produced by continuous-flow catalytic hydroprocessing of the phase separated bio-oil.

The most critical problem of processing coker gas oil (CGO) is its high nitrogen content, especially the basic nitrogen compounds, which limits its cracking performance in the fluid catalytic cracking (FCC) process. For enhancing the conversion of CGO, three processing schemes were evaluated in a pilot-scale riser FCC unit. Four indexes (thermal cracking index, dehydrogenation index, hydrogen transfer coefficient, and isomerization reaction index) were used to investigate the effects of operating conditions on the reactions of CGO cracking. Results show that the optimal operating conditions for CGO cracking are high reaction temperature and large catalyst-to-oil ratio with a short residence time. Therefore, we proposed a synergistic process by selectively recycling light FCC gasoline (LCG) from the upper position of the riser reactor, which can provide a high-severity reaction zone for CGO cracking and a low-severity reaction zone for gasoline upgrading. To further investigate the mutual effect of the two...

Coker naphtha was separated into ten distillation fractions equal in volume via Engler distillation. It was found that the mercaptan sulphur compounds were mainly concentrated in the lighter fractions, whereas the basic nitrogen compounds were concentrated in the heavier fractions. The gum content increased gradually with increasing the boiling point of each fraction after storage for 21 days under ambient conditions (25°C, 101 kPa). The active organic acidic compounds in coker naphtha extracted with aqueous solution of 20 mass % NaOH represented 0.26 mass %. The GCMS analysis of the active organic acidic compounds showed the amounts of small molecule thiols, thiophenols (including benzyl mercaptan) and phenolic compounds to be 2.6 %, 4.4 % and 90.0 %, respectively. After removal of the active acidic compounds by caustic scrubbing, the increase in the rate of gum formation was much slower than that of the blank coker naphtha after 27 days of storage under ambient conditions, indicating that the effect of these acidic compounds on the gum formation is more significant than with basic nitrogen compounds. It is demonstrated that the storage stability of coker naphtha was decreased in the presence of large amounts of phenolic compounds, which may accelerate the acid-catalysed polymerisation of olefins.

We report an experimental investigation of secondary reactions of intermediates in delayed coking. Thermal cracking reactions of intermediates, for example coker naphtha (C5 ~180 °C), light coker gas oil (LCGO, 180–350 °C), middle coker gas oil (MCGO, 350–440 °C), and heavy coker gas oil (HCGO, >440 °C), were investigated. The results reveal that cracking of coker naphtha and LCGO is low under these experimental conditions. Thermal cracking MCGO exceeds that of LCGO. Among all the intermediates, thermal cracking is greatest for HCGO. The secondary reactions of HCGO produce not only gas and liquid products, but also coke. This increase in the yields of gas and coke is attributed to secondary reactions of HCGO and MCGO. Inhibition of the secondary reactions of intermediates results in a greater yield of liquid.

The influences of the boiling point and fractional composition of coker gas oil (CGO) on the fluid catalytic cracking performance were investigated. Nitrogen compounds and condensed aromatics in CGO were identified by electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR MS) and gas chromatography-mass spectrometry (GC-MS), respectively, and their effects were studied systematically. The result shows that the catalytic cracking performance of CGO does not correspond to the boiling point of narrow fractions but rather to the basic nitrogen compounds and condensed aromatics that have high molecular weight and/or high condensation tendencies adversely. On the basis of these results, a divisional fluid catalytic cracking (DFCC) process was proposed where a separate reaction zone was added to reduce the contents and effects of the adverse compounds in CGO during catalytic cracking. The simulation experiments of the DFCC process show that improved conversion and enhance...

The coking phenomenon of coker gas oil (CGO) feedstock during fluid catalytic cracking (FCC) using a commercial equilibrium catalyst was investigated. Different types of coke formed via coker gas oil (CGO) catalytic cracking were also analyzed. The coke formed was composed of adsorption coke (Cad), dehydrogenation condensation coke (Cdh), and hydrogen transfer coke (Cht). Cad, derived from nitrogen compounds, adsorbed on the acid sites of the catalyst and accounted for 37 wt % of the total coking content under conventional reaction conditions. Cdh was formed by the dehydrogenation condensation of polycyclic aromatic hydrocarbons and accounted for about 43 wt % of the total coking content. The coking content of Cht was greatly determined by the degree of the secondary reaction. Coke selectivity can be decreased and Cht yield can be controlled by simultaneously increasing the reaction temperature and shortening the reaction time.

Carbonaceous deposits in automotive engines are the major problems associated with oil aging. Efficient detergents and dispersants have been used for several decades to solve this problem particularly in petroleum oils. But future lubricants and new engine hardware require development of new nontoxic detergent/dispersant additive technologies. Environmental concerns limit the formulation of the future lubricants. It requires not only the base oil to be ecofriendly but the additives also. In the present work, some of the potential ecofriendly chemical’s molecules were identified. Specific detergents applications along with effects of chemical modifications were evaluated by Blotters Spot and Panel Coker Tests. Among the studied compounds, the PIB (polyisobutylene) succinimides are showing promising results at lower temperature, while at higher temperature piperazine derivatives citrate and oleate have the best potential to be develop as ecofriendly detergent/dispersant additives.

Alkylation of coker diesel produced by PetroChina Fushun Petrochemical Company No. 1 Refinery was investigated in this article. Complex of aluminum trichloride and trichloromethane was used as a catalyst. Effects of catalyst amount, reaction temperature, and time on the distribution and quality of the product were studied. The results showed that when the reaction temperature was 60°C, ratio of benzene to alkene was 8:1, reactive time was 6 h, the ratio of catalyst quantity in the reactive liquid was 5% (wt), and yield of heavy alky benzene could reach 19.6%. The quality of coker diesel had been significantly improved through this method.

Selective desulphurization and denitrogenation of hydrocarbon mixtures rich in olefins (FCC-, pyrolysis- and coker naphtha) were investigated over three different catalysts (conventional and new generation CoMo/Al2O3, Pt(0.1%)Pd(0.3%)/USY). According to the experiments carried out in a wide range of operation parameters it was concluded that the sulphur removal efficiency of the PtPd/USY approximately equals to that of the new generation CoMo/Al2O3 up to about 200 mg/kg sulphur and 35 mg/kg nitrogen content, but the octane number loss is lower and the nitrogen removing efficiency is significantly better (nearly 100%) as well, than in case of the previous catalyst. In case of feedstock having higher sulphur and nitrogen content, the utilisation of CoMo/Al2O3 together with PtPd/USY in one reactor enables the production of very low sulphur (