ramin karimzadeh

In the recent years, marine natural compounds are so useful in the health and cosmetics. The small fish is one of the sources for nutritional value and biological activities, but due to their small size, they are not suitable for frying, boiling and etc. Benthosema pterotum was sampled from Oman sea. Oil extraction was performed by Blight and Dyer. First, fatty acids were separated with urea digestion and they were identified with gas chromatography. Then, in order to prepare the cream and soap, the cosmetic bases of Farabi Company were used, and finally moisture of skin with coroniometer measured. The quality of the soaps was evaluated based on the total microbial count, bacterial count of Staphylococcus aureus, coliform count, and Escherichia coli count. The soaps were made using myctophid fish oil, which contained eicosapentaenoic acid (10.4%) and docosahexaenoic acid (0.8%). The soap containing 5% myctophid oil increased skin moisture content by 0.81%. Therefore, due to the cosmetic and hygienic properties of myctophid fish oil, it can be utilized in the formulation of moisturizing and rejuvenating cosmetic products. It is hoped that, considering the nutritional and biological activities of these small fish, effective steps will be taken to produce non-oil food and cosmetic products after addressing the drawbacks of commercially extracted oils.

In this research, the batch bomb method is used to produce coke with high density and thermal conductivity. The effect of increasing and decreasing temperature and pressure, is investigated in order to synthesize a high-quality and industrial product. The main problem in this research is that the produced coke has low physical resistance which causes high corrosion in systems and high consumption in industry. The main purpose of this research is to enhance the final product by changing the two parameters of temperature and pressure, so that the physical resistance will increase and the coefficient of thermal expansion will decrease. During 42 conducted tests, the range of the temperature was varied from about 200°C to 800°C and pressure range was varied from atmospheric pressure to 4 bar, densities from about 1.28 to 1.9 grams per centimeter cube obtained and in the same way the efficiency was acheived from 15.80 to 41.68%. According to the results, it can be concluded that the most ideal temperature obtained in petroleum coke with high density and high efficiency is 600˚C to 685˚C and the most ideal pressure is also 2.5 bar.

Silica gel is a solid adsorbent known for its unique property of changing color as it adsorbs moisture. The main component in the production of silica gel is sodium silicate, which can be derived from natural raw materials such as sugarcane bagasse ash, rice husk ash and coconut shell. In this study, sodium silicate was extracted from rice husk ash (RHA), followed by the synthesis of silica gel using the sol-gel method. The resulting silica gel was then colored orange using iron (ⅠⅠⅠ) chloride salt. FE-SEM image showed a homogeneous distribution of particle size and color on the surface of the silica gel. The BET surface area of orange silica gels synthesized from commercial sodium silicate and RHA (Aging time = 24 hours) was found to be 248.6 and 179.86 m2/gr, respectively but the high Smeso/Smicro in silica gel from rice husk ash contributes to its suitable moisture adsorption capacity compared to silica gel from industrial sodium silicate.

Today, zeolitic catalysts play an important role in catalytic processes such as cracking, alkylation, etc. However, shaping these catalysts for industrial applications remains a challenge. Despite extensive research in this area in recent years, the number of studies is limited, and detailed information is scarce. Consequently, this study aims to increase awareness of the challenges associated with catalyst shaping and to contribute to the body of knowledge in this field. Following an introduction to the fundamental concepts and shaping techniques, our focus in this review has been on the binder agent, whereby we have categorized the effects of binders that can influence catalyst performance. We demonstrate that while binders may not necessarily possess catalytic properties, the chemical interaction between the binder and the catalyst, as well as the extrusion process, can significantly impact the physicochemical characteristics of the final catalyst, including its acid characteristics, pore characteristics, distribution of loaded metals, and so on. Moreover, depending on the desired properties of the catalyst, different sequences can be employed to utilize the binder. Finally, we identify research gaps in this domain and present recommendations for future studies.

Commercial activated carbon available in Iran has been used for adsorptive desulfurization from model fuel, and in order to increase its adsorption efficiency, surface modification has been done by Fe impregnation on its surface. The Fe loading on activated carbon surface has successfully increased the adsorption efficiency due to the formation of π complex and direct sulfur-metal interaction, and this adsorbent removed 80% of dibenzothiophene from model fuel, in comparison with unmodified activated carbon has 17% more adsorption performance for dibenzothiophene. Also, adsorption capacity of Fe/GAC and GAC adsorbents are 320mg/g adsorbent and 250mg/g adsorbent, respectively.
 
.

Naphtha cracking processes call for low aromatic feedstocks to satisfy the operational considerations regarding the quality of their feedstocks. Therefore, the issue of the aromatics removal from petroleum fractions has become more serious. In this study, the experimental investigation and thermodynamic modeling of the liquid-liquid equilibria of the quinary system naphtha cut (including paraffinic, naphthenic, and aromatic species), sulfolane, and water, over the temperature range of 303.2 to 333.2 K, have been studied. The molecular representatives of paraffinic, naphthenic, and aromatic species of naphtha cut have been determined based on different objective functions. Physical properties estimation and modeling of equilibrium data reveal higher accuracy of vapor pressure- and viscosity-based objective functions in the structural modeling of naphtha cut. The root-mean-square deviations for the mentioned functions were determined to be about 1.47 and 1.48%, respectively. Thermodynamic modeling with the predictive UNIFAC model showed a good agreement with the experimental measurements. Also, the interaction coefficients extracted from the 75 ºC equilibrium data led to minimum deviation in the equilibrium modeling. Finally, the phase diagrams show the noticeable effect of water content and the small effect of temperature on the system equilibria.

Used oil filters contain both significant environmental hazards and valuable components suitable for reuse, justifying their recycling. Among various recycling methods, pyrolysis has been employed in this project. This study investigates the behavior of each influential material in residue production, including used oil, rubber gasket, and filter paper, with the alteration of two parameters: temperature and residence time, individually. Experiments were conducted at temperatures of 360, 440, and 520 degrees Celsius, with two residence times of 30 and 90 minutes, under a constant nitrogen flow rate of 200 ml/min. The residue yield was measured after each experiment. In the pyrolysis of used oil, with an increase in temperature and residence time, the residue production initially decreased due to the advancement of primary thermal cracking reactions in the feed. However, secondary thermal cracking of hydrocarbons present in the reactor led to a subsequent increase in residue production. In the pyrolysis of rubber gasket, the residue production trend consistently decreased with rising temperature and residence time, indicating the progression of pyrolysis and initial thermal cracking, as well as the vaporization of solid hydrocarbon materials at higher temperatures. In the examination of the effect of temperature and residence time on filter paper pyrolysis, it was observed that increasing these parameters reduced the efficiency of residue production. This reduction could be attributed to either the initial thermal cracking of the filter paper or the secondary thermal cracking of the produced residue.

Research subject: 

Electromagnetic heating is one of the new methods of upgrading and increasing heavy oil extraction. In this method, electromagnetic waves will increase temperature, break heavy compounds, reduce viscosity, and improve and increase oil recovery.

Research approach:

 In this research, magnetic iron oxide nanoparticles (Fe3O4) were synthesized by the co-precipitation method, and the efficiency of these nanoparticles in the process of electromagnetic heating and heavy oil upgrading was investigated. Also, a comparison was made between the effect of these nanoparticles in the process of electromagnetic heating and activated carbon. In this process, oil samples containing 0.1% of Fe3O4 nanoparticles or activated carbon were irradiated with microwave (frequency 2.54 GHz and power 400 W) for 0 to 8 minutes, and the temperature and viscosity variation were investigated.

The results showed that microwave radiation increased the temperature of the samples. The temperature of the sample of crude oil, crude oil with activated carbon, and crude oil with Fe3O4 nanoparticles increased from ambient temperature to 70, 82, and 90°C, respectively, under wave radiation for 8 minutes. Also, the most significant decrease in viscosity was reported in 4 minutes: the viscosity of crude oil sample, crude oil with activated carbon, and crude oil with Fe3O4 nanoparticles under wave irradiation for 4 minutes decreased 295 mP.a to 261, 254, and 223 mP.a, respectively. In other words, the viscosity of the samples under wave irradiation for 4 minutes for crude oil, crude oil with activated carbon, and crude oil with Fe3O4 nanoparticles decreased by 11.5, 13.9 and 24.4%, respectively.

In this paper, the thermodynamic equilibrium of the methanol steam reforming process (MSR) for hydrogen production was studied by Gibbs free energy minimization method. The effect of operating parameters such as temperature and steam/methanol ratio in feed stream (Steam/Carbon) on product distribution was evaluated. In order to investigate the amount of undesirable by-product in the equilibrium state, the side-reactions progress in the hydrogen-rich stream were analyzed in the certain operating range (temperature: 300-600 K and Steam/Carbon: 0.1-3). The optimum conditions were determined for maximizing methanol conversion, high hydrogen production yield and minimizing undesirable products such as CO and DME. In order to investigate the effect of presence of methane in the reaction medium on the hydrogen production yield and products selectivity, two separate thermodynamic analyses were performed assuming the presence or absence of methane in the product stream. In the presence of methane (case 2), the maximum hydrogen yield was about 10%. The results showed that in the absence of methane in the reaction medium, the suitable operation conditions limit for obtain the highest hydrogen yield and decrease of undesirable by-products were 450-600 K and a Steam/Carbon ratio above 1.5.

This study has examined the extractive dearomatization of naphtha cracker feedstock. By considering the solvent-to-feed ratio (2:1-4:1), solvent water content (0-10 wt.%), and extraction temperature (30-60 ºC) as major operating variables and the solvent capacity, solvent selectivity, and the yield and the degree of paraffinicity of the dearomatized fraction as the response of experiments, the priority of variables in the prediction models was determined. The analysis of variance and a standard multilayer perceptron artificial neural network showed that in extractive dearomatization of the blended naphtha cut with sulfolane solvent, the priority of variables follows the trend of solvent water content, solvent-to-feed ratio, and temperature. Also, by optimizing the operation, using the penalty function approach, and defining six different single- and multi-objective functions, the optimum values of the solvent water content, solvent-to-feed ratio, and extraction temperature were found as 9.98%, 3.86:1, and 32.6 oC, respectively. Finally, the maximum values for the degree of paraffinicity and the yield of the dearomatized fraction were obtained as 94.36 and 95.95%, respectively.

The present research has studied the performance of a mixed solvent of sulfolane and 3-methyl-N-butylpyridinium dicyanimide to dearomatize the naphtha fraction of the Tehran oil refinery. Analysis of variance and artificial neural network analysis (as a standard multi-layer perceptron network) reveals that regarding the solvent selectivity, degree of product paraffinicity, and the production yield of dearomatized product, ionic liquid content in the mixed solvent has the highest degree of importance among design variables, whereas, the solvent-to-feed ratio is the most effective one in the solvent capacity response. The findings show the negligible effect of the extraction temperature and the absence of positive and negative synergistic effects between sulfolane and 3-methyl-N-butylpyridinium dicyanimide. Considering the penalty function approach and different single-objective and multi-objective functions, the optimum values of the solvent-to-feed ratio and the ionic liquid content were found as 2.03:1 and 99.47%. As a rough estimate, the mixed solvent leads to a 47% decrease in the required amount of solvent compared to the sulfolane solvent.

Today, by increasing industrial and agricultural activities and the subsequent increase in pollutants, soil and water pollution has become a serious environmental problem. The increase of pollutants in the soil in the conditions of dry climate and drought stress have adverse effects on the biological indicators. In this study the combined effect of cadmium at six levels (0, 5, 10, 20, 40 and 80 mg kg-1 soil) in the form of cadmium sulfate (CdSO4) and three irrigation intervals (2, 4 and 7 days) as a factorial experiment in the form of a completely random basic design with three replications was investigated on spinach (Spinosa oleracea) and lettuce (Lactuca sativa) in calcareous soil with silty clay texture. The obtained results showed that increasing the concentration of cadmium in the soil caused a significant decrease in the average dry weight of leaves and stems of lettuce and spinach. The average dry weight reduction percentage compared to the control at the highest level of cadmium was observed in lettuce leaves and stems as 63 and 46% and in spinach leaves and stems as 54 and 38%, respectively. Increasing the irrigation intervals decreased the dry weight of lettuce and spinach plants significantly compared to the control. The percentage of mean dry weight reduction in 4 and 7 days irrigation intervals compared to 2 days irrigation interval in lettuce leaf and stem was 23, 41, 31 and 63% and in spinach was 19, 39, 24 and 49%, respectively. The increase in cadmium levels increased the concentration of this element in the stem and leaves of lettuce and spinach plants, and by increasing irrigation intervals, the concentration and uptake of cadmium in the leaves and stems of spinach and lettuce decreased. The results of this research showed that the spinach plant absorb and transport cadmium metal more than the lettuce. The stress sensitivity index showed that the moisture stress has reduced the crop tolerance to cadmium. Based on the decrease in dry weight at different levels of cadmium, it can be said that the stem of two plants is more tolerant to cadmium than the leaf.

In the current research, lignin was successfully extracted from industrial waste Kraft black liquor using acid precipitation method. In the following step, powdered carbon was sensitized through H3PO4-chemical activation method. The effects of synthesis parameters including activation temperature (T) within the range of 400-600 ⁰C and two H3PO4/Lignin mass ratio (R) of 2 and 3 on activated carbon (AC) structure were investigated. To study the physical and morphological properties of the sensitized carbons, BET, SEM, and FTIR methods were used. The potential application of synthesized ACs was investigated by measuring their adsorption capacity in adsorption process of Methylene blue (MB) from aqueous solution. The AC sensitized at R=2 and T= 500 ⁰C (AC-2-500) showed the highest specific surface area (1573.31 m2/g) and the pore volume (0.89 cm3/g) as well as the highest adsorption capacity of MB. This adsorbent was applied in the equilibrium adsorption experiments and kinetic description. The results from kinetic experiments and adsorption isotherms indicated that the pseudo-first-order model and Langmuir model were in the most correspondence with the experimental data. Maximum adsorption capacity was 188 mg/g. The study proved that a high potential for conversion of black liquor to greatly porous Lignin-based adsorbents. Moreover, the considerable maximum adsorption capacity suggested that a noteworthy potential of Lignin-based AC for wastewater treatment.

Various organic fuels, including citric acid, ethylene glycol, glycine and urea, were used to synthesize alumina-supported NiMo catalysts via the solution combustion method and applied in thiophene hydrodesulfurization at atmospheric pressure. The as-synthesized catalysts were characterized by X-ray diffraction (XRD), Thermogravimetric analysis (TGA), Field emission scanning electron microscopy (FESEM), Energy dispersive X-ray analysis (EDX), Nitrogen adsorption/desorption, and Temperature program reduction (TPR). The results showed that the type of organic fuel has a considerable effect on the phase structure, surface morphology and reducibility potential due to the different amounts of heat and gaseous products released during the combustion reaction. Also, a relatively homogeneous distribution of the metals over support was obtained in all samples. The highest activity was obtained over a sample synthesized with citric acid as fuel due to its significant proper-ties, such as high surface area, considerable surface pore structure, and weakened metal-support interaction, compared with other fuel additives. Activity assessment of the prepared catalyst by ethylene glycol and glycine demonstrated that 100% abatement of thiophene was achieved at 105 °C and 30 min.

The increase in waste and used tires has become a serious problem in environmental pollution. As vehicles increase and the average mileage of each vehicle increases, this pollution increases every day. Having a significant amount of thermal energy in tires has made their recycling very attractive to solve environmental problems, so that the recycling of waste tires not only has no harmful effects on the environment, but also the source of industrial development and economic profitability and processing and production of other products. In this research, the aim of this study is to investigate the two-stage heat-catalytic pyrolysis process of waste tires on ZSM-5, Y and β zeolite catalysts in order to produce quality of liquid fuel. The properties of the catalysts were evaluated using X-ray diffraction (XRD) spectroscopy, scanning electron microscopy (SEM) and nitrogen adsorption-desorption analysis. The performance of commercial catalysts in the catalytic cracking of liquid product resulting from thermal pyrolysis of waste tires in the presence of nitrogen gas was investigated. The results showed that zeolite Y with liquid yield of 78.91% by weight had better performance in the above process than the other two catalysts.
.

The search for alternative ways to produce important fuels such as gasoline is crucial. One of these technologies is the process of converting methanol to gasoline, which will have a high economic position in the future. A common catalyst for the MTG process is the ZSM-5 zeolite, which, despite its many benefits, is rapidly deactivated. Therefore, the production of a suitable catalyst with high stability and resistance to coke deposition, is of great interest in the industry. In this study, the efficiency of a composite catalyst consisting of ZSM-5 and Beta zeolites in improving coke stability and distribution of liquid products has been studied. To reduce the costs, the two zeolites were synthesized using a template free method and using a cheap natural source like rice husk. The results showed that with the introduction of Beta zeolite, the acidity of the composite catalyst decreased, which in addition to improving the structural properties of the catalyst by creating mesopores, improved the performance in the MTG process so that on this catalyst, deactivation time increased by 60%. Moreover, the study of process kinetics using Crambeck model, which included 3 lumps of methanol / dimethyl ether, light olefins and gasoline, showed that the results of the model were in good agreement with the results of the laboratory datas.

Samples of low-cost activated carbons were synthesized from rose damascena waste by chemical activation using KOH as an activator with different KOH to rose damascena waste ratios (0.5, 1 and 2) as named ACR-0.5, ACR-1, ACR-2.  One sample was loaded with copper nanoparticles (ACR-2-Cu). The synthesized activated carbons have been characterized using FESEM (Field Emission Scanning electron microscopy), FTIR (Fourier transform infrared spectroscopy) and BET surface area analyzer. All activated carbon samples were used in desulfurization of a model diesel fuel composed of n-Heptane   4,6-dimethyldibenzothiophene (4,6-DMDBT) as sulfur containing compound. Results showed that ACRs with BET surface areas up to 1330-2155  were obtained. The BET surface areas and pore volumes increased with KOH to rose damascena waste ratio and Cu functionalization. More than 95% of 4,6-DMDBT adsorption capacity was reached in the first 10 min of adsorption experiment. The efficiency of sulfur removal by ACR was increased by enhancement the KOH to rose damascena waste ratio and by Cu functionalization. The 4,6-DMDBT adsorption capacity follows the order: ACR-2-Cu> ACR-2> ACR-1> ACR-0.5. The maximum adsorption capacity of ACR-2-Cu sample to 4,6-DMDBT was 24 mg S/gr adsorbent and the adsorption capacity was related to the volume of narrow micropores and Cu nanoparticles. The kinetic data was well described by pseudo-second and first-order kinetic models and the equilibrium adsorption data was well fitted to the Langmuir and Freundlich models to estimate the adsorption parameters.

This study was conducted to investigate the possible effects of cages culture Asian sea bass fish (Lates calcarifer) on the population structure of macrobenthos in the Rigo area of Qeshm Island in Hormozgan province during a breeding period in 1397 were investigated. The average abundance of macrobenthos at the location of the cages culture and the refrences site in this study was equal to (52765 ± 19154 in m2) and (50642 ± 21002 in m2), respectively.The results showed that at the time of the study among the identified the genus of Ammonia sp. With a relative abundance of 73.41 percent at the location of the cages compared to the control station and Archasterope sp., Spirolochulina sp. and Nephtys sp. with a relative abundance of 63.9%, 49.1% and 12.6%, respectively, were more dominant in the control station compared to the location of the cages.The loading rate of organic matter in the bed of the cages was significantly affected by fish farming activities and in some times showed a significant difference with the control station (P<0.05). In general, at the time of the study, activities related to fish farming in cages had no effect on the population structure of macrobenthos in the study area.

Biological control using marine bacteria is part of the integrated management to control harmful algal blooms (HABs). The aim of the present study was to investigate the frequency and diversity of bacteria in HAB-exposed regions in Hormozgan province and to evaluate their algicidal activity against Cochlodinium polykrikoides. Seasonal frequency of bacteria in 10 stations throughout the coastal regions of Hormuz Island, Bandar Abbas, and Bandar Lengeh showed maximum frequency in St 1, St 6, and St 10 in spring. We identified 10 bacterial families in sediment samples, which dominantly belonged to Vibrionaceae, Entrobacteriaceae and Pseudomonadaceae with 29%, 14 %, and 12% frequency, respectively. While in seawater samples Entrobacteriaceae and Vibrionaceae were dominated with 23% among 6 identified families. Approximately, 13.33% of sediment-isolated bacteria and 9.09% of seawater-isolated bacteria were able to kill whole algal cells. The extracted metabolites of the active isolates exhibited significant algicidal activity with LC50 values ranging from 90.28±3.14 to 1029±45.94 µg/ml. This study presented an overview of the frequency and diversity of bacteria in the investigated areas and provided eight algicidal isolates for future studies on the biological control of HABs.

Activated carbon is a porous absorbent with reasonable specific surface area, pore volume, and pore size distribution for many applications such as adsorption. This material is obtained from various natural sources of carbon. Due to increasing demand for activated carbon, the economical precursors have been highly noticed. In the meanwhile, black liquor, industrial residue from Lignin Kraft process in paper factories, has high amount of carbon which can be used as an appropriate and cheap precursor for activated carbon production, and make high value added.

In this study, at first, lignin was extracted from black liquor, prepared from Iran wood & paper industries-Chouka factory, under defined conditions and investigation of pH effect, and then, powdered carbon was synthesized from extracted lignin using chemical activation method by phosphoric acid chemical agent. To consider the effects of activation temperature parameter on activated carbon structure, including specific surface area, pore volume, and pore size distribution, three activation temperature of 400, 500 and 600 ⁰C in impregnation ratio of 2 were investigated. To study the physical and morphological properties of sensitized absorbents, they were analyzed by BET, SEM, and FTIR methods.

The results confirmed that the highest amount of lignin with a similar structure to the degraded lignin was recovered at pH = 2. Investigation of the effect of activation temperature parameter suggested that the activation temperature of 500 °C can be a reasonable temperature for the synthesis of high specific surface area activated carbon and increasing the temperature above 500 °C is not effective. Among these sensitized adsorbents, the activated carbon sensitized in activation temperature of 500 ⁰C showed the highest specific surface area and the pore volume of 1573.31 m2/g and 0.89 cm3/g respectively, which exhibits the high potential of this precursor as activated carbon adsorbent.

In the present study, performance of three catalysts containing Y, ZSM-5 and Beta zeolite in the catalytic cracking of a kind of middle distillate cut named ”RCD” has been studied. The catalysts were characterized by XRD, FTIR, SEM, N2 adsorption/ desorption and NH3-TPD techniques. Furthermore, deactivated catalysts in terms of type and amount of deposited coke were analysed. Results of catalytic tests showed that Y zeolite performed better and it decreased viscosity and density of liquid product by 35% and 3% respectively. This good operating was due to the high surface area (812m2/gr) and higher acidic sites amounts(1.8 mmol NH3/gr) which gives the heavy molecules better accesibility to active acid sites .But more cokes have deposited on Y zeolite which was 50% lower for Beta and ZSM-5 zeolites. Finally, it can be concluded that the ultimate performance of catalysts in catalytic cracking is influenced by the synergetic effects between the pore structure and acidity.

In this study, the aim is to extract pure amorphous silica from rice husk ash by acid leaching, then calcination and base leaching, and finally titration by acid. Then, the synthesis of adsorbents was performed through loading of copper, zinc and cerium at the rate of 13% by weight of metal by impregnation method on silica support. Finally, the performance of the synthesized adsorbents in the adsorptive desulfurization process was investigated to remove 4, 6-dimethyldibenzothiophene from the model fuel. Nitrogen adsorption - desorption isotherms for the samples showed that the pores are in the mesopore range. The highest adsorption capacity was obtained at a concentration of 500 ppm for CuO/SiO2 adsorbent equal to 23.7 mg/g. Also, by examining the Langmuir, Freundlich and Dubinin-Radushkevich equilibrium isotherms, the Langmuir isotherm was most consistent with the experimental data. Also, according to Dubinin-Radushkevich isotherm it was proved that the dominant mechanism in adsorption is chemical. In order to investigate the adsorption kinetics in this study, pseudo-first order and pseudo-second order equations were also examined. The pseudo-second order kinetic was fitted with experimental data with R-squared of 0.99 were fitted to the experimental data. BET and FESEM equipped with EDX analyzes have been used to investigate the physicochemical properties of the synthesized adsorbents. Also, the concentration of fuel solution was determined by UV-VIS.

A series of Fe2O3(83%)-ZrO2(7.5%)-Al2O3(7%)-CeO2(2.5%) catalysts were synthesized with co-precipitation method in different aging times (0 to 6 hours) using the metal nitrate precursors. Physicochemical properties of the prepared catalysts characterized with X-Ray Diffraction (XRD), Field Emission Scanning Electron Microscopy (FE-SEM), EDX, Nitrogen Adsorption-Desorption, Thermal gravimetric analysis (TGA) and H2-Temperature programmed reduction (H2-TPR) analyses. The catalytic performance of the synthesized catalysts was also evaluated by the steam catalytic cracking of the Vacuum bottom (VB). The results showed that increasing the aging time improved the textural properties of the catalysts in the oxygen adsorption capacity from steam, as well as the control of the catalyst surface area to produce a higher quality liquid product. When Cat-6 (catalyst with aging time of 6 h) was used as the catalyst, the yield of gasoline cut (boiling point range 27-225 ), diesel cut (boiling point range 200-320 ) and VGO cut (boiling point range 320-450 ) production was 25.3 mass %, 47.7 mass % and 33.8 mass %, respectively. Furthermore, Cat-6 showed higher performance in the partial oxidation of VB.

In this study, a six-lump kinetic model is proposed for describing the catalytic cracking of gas oil over Y zeolite. The feedstock and products were classified into six discrete lumps, including feed, kerosene, gasoline, liquefied petroleum gas, dry gas, and coke. A time-on-stream exponential function was used to describe the deactivation mechanism. Experimental data for 5 temperatures between 500-600 °C and residence time of 60-120 s were applied for the estimation of kinetic parameters. The estimated activation energies were in the range of 40–85 kJ.mol−1, the preliminary reactions exhibited lower apparent activation energies than secondary reactions. By increasing the reaction temperature from 500 ° C to 650 ° C at the reaction time of 240 min, the progress of the secondary reactions of coke production increases, and the deactivation function decreases from 0.955 to 0.735, After 300 min it reached 0.892 and 0.466, respectively. This means that at higher temperatures, the catalyst deactivation occurred faster. Analyzing the results for the distribution of products under different operating conditions showed that a temperature of 550 ° C and a residence time of 60 to 80 s are optimal for the production of gasoline and kerosene.

In this research, the possibility of asphaltene separation from the vacuum tower residue using the low cost industrial solvents such as 402, 404, 406, and 410 was investigated. In order to separate asphaltene the IP143/01 and ASTM D 3279-07 separation methods were utilized. In order to find the optimal state of asphaltene precipitation, Design of experiments software with three factors of residence time, the solvent-to-feed ratio and the volume percent of 406 solvent to the total solvent of 406 and 410 were used. The results showed that the effectiveness of each parameter in precipitating the asphaltene attributed to the ratio of solvent to feed, the ratio of solvent 406 to total solvent, and the residence time, respectively and there was a significant interaction between the basic parameters. The best asphaltene precipitation of 5.06% of 7.5% happens at the residence time of 36.97 hours, the ratio of solvent to feed of 35.95 ml/gr and the volume percent of 406 solvent to the total solvent of 27.20%. Asphaltene precipitation percentage for the optimal mixture of industrial solvents was 22.5% lower than the precipitated asphaltene from normal heptane solvent. However, according to the solvents price, industrial solvents (410 and 406) were approximately 50% cheaper than normal heptane, and hence on overall, there was a cost savings of more than 20%