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Badoga, Sandeep_PhD_thesis_April_20152015 April 1900 (has links)
Bitumen-derived heavy gas oil contains large amounts of sulfur (~4.0 wt.%) and nitrogen (~0.4 wt.%), which need to be lowered before it becomes suitable as a feedstock for refineries. The most widely used upgrading process is hydrotreating, and the conventional catalyst used for hydrotreating is Ni or Co and Mo or W supported on γ-Al2O3. Additionally, environmentally driven regulations impose strict limits on sulfur and nitrogen levels in transportation fuels. Therefore, the main focus of this work was to enhance the activity of a NiMo supported catalyst through its modification and to improve its selectivity to removal of bulky sulfur- and nitrogen-containing compounds from heavy gas oil under industrial hydrotreating conditions. This work was divided into four phases, and this thesis summarizes the research outcomes of each phase.
The first phase examined the effects of chelating ligands, specifically, ethylenediaminetetraacetic acid (EDTA), on hydrotreating activity and the sulfidation mechanism. EDTA was seen to have a beneficial effect on hydrotreating activity. Detailed mechanistic aspects of interactions between support and EDTA, EDTA and metallic species, support and metal, support and active phase, and metallic species and metallic species at different reaction conditions, were also studied. Characterization by XANES revealed that the presence of a chelating agent delayed nickel sulfidation, which was the main cause of improvement in hydrodesulfurization (HDS) and hydrodenitrogenation (HDN) activities. It also showed that EDTA plays a role in redistribution of active phases during sulfidation and favors the formation of octahedral molybdenum oxides.
The second phase studied the effects of support modification and combinations of different supports and EDTA. In this phase, several mesoporous materials, including M-SBA-15 (M= Al, Ti and Zr), mesoporous mixed metal oxides (TiO2-Al2O3, ZrO2-Al2O3 andSnO2-Al2O3) and mesoporous metal oxides (ZrO2, Al2O3), were synthesized and used as support materials for a NiMo catalyst. NiMo/M-SBA-15 catalysts showed higher HDS and HDN activities and, the increase in activity is attributed to incorporation of heteroatoms in an SBA-15 matrix, which resulted in increase in metal support interaction, acidic strength and dispersion of active metals. The addition of EDTA to these catalysts helps in the formation of octahedral molybdenum oxide, which are easily reducible during sulfidation. This is evident from the XANES Mo LIII-edge study of the oxide catalysts. The increase in hydrodenitrogenation (HDN), hydrodesulfurization (HDS) and hydrodearomatization (HDA) activities as compared to that shown by the NiMo/γ-Al2O3 catalyst were also observed on addition of EDTA in large-pore, high-surface-area mesoporous zirconia supported NiMo catalysts. The incorporation of different metal oxides in alumina, as in the case of mixed metal oxides, resulted in a change in acidic strength and metal support interactions. It was observed with acridine-FTIR analysis that the catalysts with higher acidic strength tightly held acridine at high temperatures. This implies that catalysts with higher acidity are prone to inhibition by nitrogen-containing compounds present in feed, which will affect catalytic activity. The HDS and HDN activities for hydrotreating of heavy gas oil suggest that mesoporous alumina and titania-alumina supported catalysts perform better as compared to the conventional NiMo/γ-Al2O3 catalyst. Therefore, the effects of EDTA to Ni molar ratio (EDTA/Ni = 0 to 2) on the activities of the NiMo/MesoAl2O3 and NiMo/MesoTiO2-Al2O3 catalysts were studied, and EDTA was observed to have a negative impact on catalytic activity for these catalysts. This is attributed to a decrease in the active metal dispersion in these catalysts caused by the addition of EDTA. The catalysts NiMo/MesoAl2O3 and NiMo/MesoTiO2-Al2O3 without EDTA showed high active metal dispersion due to their high surface area and ordered structure.
The third phase studied the combined effects of phosphorus and EDTA on the hydrotreating activity of NiMo supported catalysts. The effects of method of phosphorus addition (sequential and co-impregnation method) were also studied. When phosphorus was added using a co-impregnation method, as in the catalyst NiMoP/MesoAl2O3(CI), an increase in HDN, HDA and HDS activities was observed. However, the catalysts containing both EDTA and phosphorus showed a decrease in HDS and HDN activities.
The fourth phase included a kinetic study using the Power Law and L-H models. The catalyst, NiMoP/mesoAl2O3(CI), was found to have higher HDN and HDS activities as compared to a conventional γ-Al2O3 supported catalyst containing phosphorus.
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Effect of pore diameter variation of FeW/SBA-15 supported catalysts on hydrotreating of heavy gas oil from Athabasca bitumenBoahene, Philip Effah 24 June 2011
The pore diameter of a catalyst support controls the diffusion of reactant molecules to the catalytic active sites; thus, affecting the rates and conversions of the hydrotreating reactions. Desirable textural properties of SBA-15 makes it a potential alternative to the conventionally used γ-Al2O3 support due to the fact that its pore size can be manipulated via controlling the synthesis parameters, while maintaining relatively high surface area. Larger pore diameter SBA-15 supports may facilitate the diffusion of bulky molecules as that of the asphaltenes present in the heavy petroleum fractions, making it a potential catalyst support for hydrotreating operations.
Considering the very sour nature of Canadas bitumen with high sulfur contents in the range of 2-6 wt %, the appreciably high sulfur contents particularly present in Athabasca derived heavy gas oils (about 4 wt % sulfur), the rising demand for cleaner fuels, and also the increasing stringency on environmental standards, the need for novel and improved hydrotreating catalysts cannot be overemphasized. By varying the molar ratio of hexane to ammonium fluoride, the pore channels of SBA-15 could be varied. Controlling the pore diameter of these supports via micelle swelling facilitated the production of larger pore diameter SBA-15-supported catalysts.
In this project, four mesoporous silica SBA-15 catalyst supports with pore diameters in the range of 5-20 nm were synthesized in the preliminary phase using hexane as the micelle swelling agent and subsequently utilized for the loading of 2 wt.% Fe and 15 wt.% W catalyst metals, respectively. The hexagonal mesoscopic structure of these materials were characterized using powder small-angle X-ray scattering (SAXS), N2 adsorption-desorption isotherms, TEM and SEM images. Powder XRD analysis evidenced inhomogeneous metal dispersion on the largest pore diameter catalyst. An optimum pore diameter of 10 nm was found for Cat-B and subsequently used to obtain the optimum Fe and W loadings required to achieve the best hydrodesulfurization (HDS) and hydrodenitrogenation (HDN) activities.
The optimum catalyst was found to be Cat-H with metal loadings of 3 wt.% Fe and 30 wt.% W. At these loadings and temperatures of 375°C, 388°C, and 400°C, HDS activities of 53.4%, 64.1%, and 73.3% with corresponding HDN activities of 21.9%, 26.2%, and 38.3%, respectively, were recorded. Catalytic performance evaluations conducted on equal mass loading using a reference commercial γ-Al2O3-supported FeW catalyst offered HDS activities of 69.3%, 80.4%, and 89.1%, with corresponding HDN activities of 16.4%, 32.4%, and 49.3% at the same temperatures studied. However, no significant changes in HDS and HDN activities were observed for similar evaluations on volume percent metals loading basis.
Kinetic studies performed with the optimum FeW/SBA-15 catalyst suggested activation energies of 147.2 and 150.6 kJ/mol for HDS and HDN, respectively, by the Langmuir-Hinshelwoods model. Similar results were predicted by the Power Law and Multi-parameter models for HDS (129.6 and 126.7 kJ/mol, respectively), which does not conclusively make the latter model clearly stand out as the best. Data fitting by the Power Law suggested reaction orders of 2 and 1.5 for HDS and HDN, which seem to be consistent for the hydrotreatment of heavy gas oil. Finally, a long-term deactivation study spanning a period of 60 days time-on-stream showed the optimum catalyst to be stable under hydrotreating experiments conducted in a downward flow micro-trickle bed reactor at temperature, pressure, liquid hourly space velocity (LHSV), and gas/oil ratio of 375400˚C, 8.8 MPa, 1h-1, and 600 mL/mL (at STP), respectively.
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Effect of pore diameter variation of FeW/SBA-15 supported catalysts on hydrotreating of heavy gas oil from Athabasca bitumenBoahene, Philip Effah 24 June 2011 (has links)
The pore diameter of a catalyst support controls the diffusion of reactant molecules to the catalytic active sites; thus, affecting the rates and conversions of the hydrotreating reactions. Desirable textural properties of SBA-15 makes it a potential alternative to the conventionally used γ-Al2O3 support due to the fact that its pore size can be manipulated via controlling the synthesis parameters, while maintaining relatively high surface area. Larger pore diameter SBA-15 supports may facilitate the diffusion of bulky molecules as that of the asphaltenes present in the heavy petroleum fractions, making it a potential catalyst support for hydrotreating operations.
Considering the very sour nature of Canadas bitumen with high sulfur contents in the range of 2-6 wt %, the appreciably high sulfur contents particularly present in Athabasca derived heavy gas oils (about 4 wt % sulfur), the rising demand for cleaner fuels, and also the increasing stringency on environmental standards, the need for novel and improved hydrotreating catalysts cannot be overemphasized. By varying the molar ratio of hexane to ammonium fluoride, the pore channels of SBA-15 could be varied. Controlling the pore diameter of these supports via micelle swelling facilitated the production of larger pore diameter SBA-15-supported catalysts.
In this project, four mesoporous silica SBA-15 catalyst supports with pore diameters in the range of 5-20 nm were synthesized in the preliminary phase using hexane as the micelle swelling agent and subsequently utilized for the loading of 2 wt.% Fe and 15 wt.% W catalyst metals, respectively. The hexagonal mesoscopic structure of these materials were characterized using powder small-angle X-ray scattering (SAXS), N2 adsorption-desorption isotherms, TEM and SEM images. Powder XRD analysis evidenced inhomogeneous metal dispersion on the largest pore diameter catalyst. An optimum pore diameter of 10 nm was found for Cat-B and subsequently used to obtain the optimum Fe and W loadings required to achieve the best hydrodesulfurization (HDS) and hydrodenitrogenation (HDN) activities.
The optimum catalyst was found to be Cat-H with metal loadings of 3 wt.% Fe and 30 wt.% W. At these loadings and temperatures of 375°C, 388°C, and 400°C, HDS activities of 53.4%, 64.1%, and 73.3% with corresponding HDN activities of 21.9%, 26.2%, and 38.3%, respectively, were recorded. Catalytic performance evaluations conducted on equal mass loading using a reference commercial γ-Al2O3-supported FeW catalyst offered HDS activities of 69.3%, 80.4%, and 89.1%, with corresponding HDN activities of 16.4%, 32.4%, and 49.3% at the same temperatures studied. However, no significant changes in HDS and HDN activities were observed for similar evaluations on volume percent metals loading basis.
Kinetic studies performed with the optimum FeW/SBA-15 catalyst suggested activation energies of 147.2 and 150.6 kJ/mol for HDS and HDN, respectively, by the Langmuir-Hinshelwoods model. Similar results were predicted by the Power Law and Multi-parameter models for HDS (129.6 and 126.7 kJ/mol, respectively), which does not conclusively make the latter model clearly stand out as the best. Data fitting by the Power Law suggested reaction orders of 2 and 1.5 for HDS and HDN, which seem to be consistent for the hydrotreatment of heavy gas oil. Finally, a long-term deactivation study spanning a period of 60 days time-on-stream showed the optimum catalyst to be stable under hydrotreating experiments conducted in a downward flow micro-trickle bed reactor at temperature, pressure, liquid hourly space velocity (LHSV), and gas/oil ratio of 375400˚C, 8.8 MPa, 1h-1, and 600 mL/mL (at STP), respectively.
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Modelling and optimisation of oxidative desulphurization process for model sulphur compounds and heavy gas oil : determination of rate of reaction and partition coefficient via pilot plant experiment : modelling of oxidation and solvent extraction processes : heat integration of oxidation process : economic evaluation of the total processKhalfalla, Hamza Abdulmagid January 2009 (has links)
Heightened concerns for cleaner air and increasingly more stringent regulations on sulphur content in transportation fuels will make desulphurization more and more important. The sulphur problem is becoming more serious in general, particularly for diesel fuels as the regulated sulphur content is getting an order of magnitude lower, while the sulphur contents of crude oils are becoming higher. This thesis aimed to develop a desulphurisation process (based on oxidation followed by extraction) with high efficiency, selectivity and minimum energy consumption leading to minimum environmental impact via laboratory batch experiments, mathematical modelling and optimisation. Deep desulphurization of model sulphur compounds (di-n-butyl sulphide, dimethyl sulfoxide and dibenzothiophene) and heavy gas oils (HGO) derived from Libyan crude oil were conducted. A series of batch experiments were carried out using a small reactor operating at various temperatures (40-100 °C) with hydrogen peroxide (H2O2) as oxidant and formic acid (HCOOH) as catalyst. Kinetic models for the oxidation process are then developed based on 'total sulphur approach'. Extraction of unoxidised and oxidised gas oils was also investigated using methanol, dimethylformamide (DMF) and N-methyl pyrolidone (NMP) as solvents. For each solvent, the 'measures' such as: the partition coefficient (KP), effectiveness factor (Kf) and extractor factor (Ef) are used to select the best/effective solvent and to find the effective heavy gas oil/solvent ratios. A CSTR model is then developed for the process for evaluating viability of the large scale operation. It is noted that while the energy consumption and recovery issues could be ignored for batch experiments these could not be ignored for large scale operation. Large amount of heating is necessary even to carry out the reaction at 30-40 °C, the recovery of which is very important for maximising the profitability of operation and also to minimise environmental impact by reducing net CO2 release. Here the heat integration of the oxidation process is considered to recover most of the external energy input. However, this leads to putting a number of heat exchangers in the oxidation process requiring capital investment. Optimisation problem is formulated using gPROMS modelling tool to optimise some of the design and operating parameters (such as reaction temperature, residence time and splitter ratio) of integrated process while minimising an objective function which is a coupled function of capital and operating costs involving design and operating parameters. Two cases are studied: where (i) HGO and catalyst are fed as one feed stream and (ii) HGO and catalyst are treated as two feed streams. A liquid-liquid extraction model is then developed for the extraction of sulphur compounds from the oxidised heavy gas oil. With the experimentally determined KP multi stage liquid-liquid extraction process is modelled using gPROMS software and the process is simulated for three different solvents at different oil/solvent ratios to select the best solvent, and to obtain the best heavy gas oil to solvent ratio and number of extraction stages to reduce the sulphur content to less than 10 ppm. Finally, an integrated oxidation and extraction steps of ODS process is developed based on the batch experiments and modelling. The recovery of oxidant, catalyst and solvent are considered and preliminary economic analysis for the integrated ODS process is presented.
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Catalytic performances of NiMo/Zr-SBA-15 catalysts for the hydrotreating of bitumen derived heavy gas oilBiswas, Piyali 26 May 2011
Gas-oil obtained from bitumen contains a significant amount of impurities, which are difficult to remove using a conventional alumina supported hydrotreating catalyst. Innumerable studies have been carried out to develop a highly effective hydrotreating catalyst, and among all utilizing more advanced support is considered as a better alternative. Recently, SBA-15, which is an ordered mesoporous silica support, has received importance as a catalyst support because of its excellent textural properties. However, SBA-15 lacks surface acidity and provides very low metal-support interaction. By modifying SBA-15 with zirconia, an optimum level of surface acidity and Si-Mo interaction can be achieved. Also, by doping zirconia with SBA-15, the textural properties of zirconia can be improved. Hence, a synergistic effect can be obtained while incorporating zirconia onto SBA-15 and the resulting material Zr-SBA-15 can be used as an effective support for hydrotreating catalyst. In the present study, Zr-SBA-15 supports were prepared by the post synthesis and the direct synthesis method with different zirconia loading. Zr-SBA-15 supported NiMo catalysts were prepared by incipient wetness impregnation technique. Catalysts and supports were characterized by small angle X-ray scattering (SAXS), nitrogen adsorption/desorption (BET), powder X-ray diffraction (XRD), transmission electron spectroscopy (TEM), scanning electron microscopy (SEM), and Raman spectroscopy methods.<p>
Characterization of support confirmed that the zirconia was successfully incorporated in a mesoporous SBA-15 structure without significantly changing the textural properties of SBA-15. The performance of the Zr-SBA-15 supported NiMo catalysts was evaluated based on hydrodesulfurization and hydrodenitrogenation activities exhibited during hydrotreating of heavy gas oil derived from Athabasca bitumen at industrial operating condition (temperature 375-395 °C, pressure 8.9 MPa, LHSV 1.0 hr-1 and gas/oil ratio 600 Nm3/m3). The comparison of catalytic activities showed that the NiMo catalysts supported on Zr-SBA-15, prepared by direct and post synthesis method exhibited higher hydrotreating activity compared to SBA-15 supported catalyst. NiMo catalyst supported on Zr-SBA-15 with 23 wt% of ZrO2 loading, prepared by post synthesis method showed the highest activity among all the catalysts.<p>
After determining the best support, the optimum catalyst metal loadings on the Zr-SBA-15 support was found to be 17 wt% of Mo and 3.4 wt% of Ni. This catalyst also showed higher activity in mass basis for the hydrotreating of heavy gas oil compared to that of commercial hydrotreating catalyst.<p>
A kinetic study was performed on the optimum NiMo/Zr-SBA-15 catalyst to predict its HDS and HDN activities while varying the parameters of temperature, liquid hourly space velocity (LHSV), pressure and gas-to-oil ratio. Rate expressions were developed using Power Law and Langmuir-Hinshelwood model to predict the behavior of both the HDS and HDN reactions. Power law models were best fit with reaction orders of 1.8 and 1.3, and activation energies of 115 kJ/mol and 121 kJ/mol, for HDS and HDN reactions, respectively. The activation energies calculated using Langmuir-Hinshelwood model considering H2S inhibition were found to be 122 kJ/mol and 138 kJ/mol, for HDS and HDN reactions, respectively.
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Catalytic performances of NiMo/Zr-SBA-15 catalysts for the hydrotreating of bitumen derived heavy gas oilBiswas, Piyali 26 May 2011 (has links)
Gas-oil obtained from bitumen contains a significant amount of impurities, which are difficult to remove using a conventional alumina supported hydrotreating catalyst. Innumerable studies have been carried out to develop a highly effective hydrotreating catalyst, and among all utilizing more advanced support is considered as a better alternative. Recently, SBA-15, which is an ordered mesoporous silica support, has received importance as a catalyst support because of its excellent textural properties. However, SBA-15 lacks surface acidity and provides very low metal-support interaction. By modifying SBA-15 with zirconia, an optimum level of surface acidity and Si-Mo interaction can be achieved. Also, by doping zirconia with SBA-15, the textural properties of zirconia can be improved. Hence, a synergistic effect can be obtained while incorporating zirconia onto SBA-15 and the resulting material Zr-SBA-15 can be used as an effective support for hydrotreating catalyst. In the present study, Zr-SBA-15 supports were prepared by the post synthesis and the direct synthesis method with different zirconia loading. Zr-SBA-15 supported NiMo catalysts were prepared by incipient wetness impregnation technique. Catalysts and supports were characterized by small angle X-ray scattering (SAXS), nitrogen adsorption/desorption (BET), powder X-ray diffraction (XRD), transmission electron spectroscopy (TEM), scanning electron microscopy (SEM), and Raman spectroscopy methods.<p>
Characterization of support confirmed that the zirconia was successfully incorporated in a mesoporous SBA-15 structure without significantly changing the textural properties of SBA-15. The performance of the Zr-SBA-15 supported NiMo catalysts was evaluated based on hydrodesulfurization and hydrodenitrogenation activities exhibited during hydrotreating of heavy gas oil derived from Athabasca bitumen at industrial operating condition (temperature 375-395 °C, pressure 8.9 MPa, LHSV 1.0 hr-1 and gas/oil ratio 600 Nm3/m3). The comparison of catalytic activities showed that the NiMo catalysts supported on Zr-SBA-15, prepared by direct and post synthesis method exhibited higher hydrotreating activity compared to SBA-15 supported catalyst. NiMo catalyst supported on Zr-SBA-15 with 23 wt% of ZrO2 loading, prepared by post synthesis method showed the highest activity among all the catalysts.<p>
After determining the best support, the optimum catalyst metal loadings on the Zr-SBA-15 support was found to be 17 wt% of Mo and 3.4 wt% of Ni. This catalyst also showed higher activity in mass basis for the hydrotreating of heavy gas oil compared to that of commercial hydrotreating catalyst.<p>
A kinetic study was performed on the optimum NiMo/Zr-SBA-15 catalyst to predict its HDS and HDN activities while varying the parameters of temperature, liquid hourly space velocity (LHSV), pressure and gas-to-oil ratio. Rate expressions were developed using Power Law and Langmuir-Hinshelwood model to predict the behavior of both the HDS and HDN reactions. Power law models were best fit with reaction orders of 1.8 and 1.3, and activation energies of 115 kJ/mol and 121 kJ/mol, for HDS and HDN reactions, respectively. The activation energies calculated using Langmuir-Hinshelwood model considering H2S inhibition were found to be 122 kJ/mol and 138 kJ/mol, for HDS and HDN reactions, respectively.
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Modelling and optimisation of oxidative desulphurization process for model sulphur compounds and heavy gas oil. Determination of Rate of Reaction and Partition Coefficient via Pilot Plant Experiment; Modelling of Oxidation and Solvent Extraction Processes; Heat Integration of Oxidation Process; Economic Evaluation of the Total Process.Khalfalla, Hamza Abdulmagid January 2009 (has links)
Heightened concerns for cleaner air and increasingly more stringent regulations on
sulphur content in transportation fuels will make desulphurization more and more
important. The sulphur problem is becoming more serious in general, particularly for
diesel fuels as the regulated sulphur content is getting an order of magnitude lower,
while the sulphur contents of crude oils are becoming higher. This thesis aimed to
develop a desulphurisation process (based on oxidation followed by extraction) with
high efficiency, selectivity and minimum energy consumption leading to minimum
environmental impact via laboratory batch experiments, mathematical modelling and
optimisation.
Deep desulphurization of model sulphur compounds (di-n-butyl sulphide, dimethyl
sulfoxide and dibenzothiophene) and heavy gas oils (HGO) derived from Libyan crude
oil were conducted. A series of batch experiments were carried out using a small reactor
operating at various temperatures (40 ¿ 100 0C) with hydrogen peroxide (H2O2) as
oxidant and formic acid (HCOOH) as catalyst. Kinetic models for the oxidation process
are then developed based on `total sulphur approach¿. Extraction of unoxidised and
oxidised gas oils was also investigated using methanol, dimethylformamide (DMF) and
N-methyl pyrolidone (NMP) as solvents. For each solvent, the `measures¿ such as: the
partition coefficient (KP), effectiveness factor (Kf) and extractor factor (Ef) are used to
select the best/effective solvent and to find the effective heavy gas oil/solvent ratios.
A CSTR model is then developed for the process for evaluating viability of the large
scale operation. It is noted that while the energy consumption and recovery issues could
be ignored for batch experiments these could not be ignored for large scale operation.
Large amount of heating is necessary even to carry out the reaction at 30-40 0C, the
recovery of which is very important for maximising the profitability of operation and
also to minimise environmental impact by reducing net CO2 release. Here the heat
integration of the oxidation process is considered to recover most of the external energy
input. However, this leads to putting a number of heat exchangers in the oxidation
process requiring capital investment. Optimisation problem is formulated using
gPROMS modelling tool to optimise some of the design and operating parameters (such
as reaction temperature, residence time and splitter ratio) of integrated process while
minimising an objective function which is a coupled function of capital and operating
costs involving design and operating parameters. Two cases are studied: where (i) HGO
and catalyst are fed as one feed stream and (ii) HGO and catalyst are treated as two feed
streams.
A liquid-liquid extraction model is then developed for the extraction of sulphur
compounds from the oxidised heavy gas oil. With the experimentally determined KP
multi stage liquid-liquid extraction process is modelled using gPROMS software and the
process is simulated for three different solvents at different oil/solvent ratios to select the best solvent, and to obtain the best heavy gas oil to solvent ratio and number of
extraction stages to reduce the sulphur content to less than 10 ppm.
Finally, an integrated oxidation and extraction steps of ODS process is developed based
on the batch experiments and modelling. The recovery of oxidant, catalyst and solvent
are considered and preliminary economic analysis for the integrated ODS process is
presented.
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Otimização da co-pirólise de gasóleo pesado com embalagens de PEAD pós-uso utilizando planejamento fatorial / Optimization co-pyrolysys from HDPE and heavy gas oil using factorial design methodologyNey Joppert Junior 07 January 2015 (has links)
A co-pirólise é uma rota promissora, uma vez que minimiza o impacto ambiental causado pela disposição do plástico de maneira inadequada, evita seu acúmulo em lixões e permite um melhor aproveitamento de um recurso natural não-renovável, o petróleo, matéria prima importante para a geração de energia e obtenção de produtos químicos. O presente trabalho teve como objetivo a definição das condições experimentais mais propícias à obtenção de líquidos pirolíticos com alta fração de óleo diesel, resultantes da co-pirólise de polietileno de alta densidade (PEAD) pós-consumo com gasóleo pesado tilizando-se catalisador de FCC (Fluid Catalytic Cracking). Como instrumento de otimização das condições experimentais, optou-se pela Metodologia Planejamento Fatorial. Foi também
estudado o efeito das condições experimentais, como: a temperatura de reação, a relação gasóleo/polietileno e a quantidade de catalisador no meio reacional. As amostras de
polietileno, gasóleo e catalisador foram submetidas à co-pirólise em sistema de leito fixo, sob fluxo constante de nitrogênio, variando-se a temperatura entre 450 C a 550 C, a quantidade de PEAD no meio reacional foi de 0,2 a 0,6 g, e a quantidade de catalisador foi de zero a 0,06 g, mantendo-se fixa a quantidade de gasóleo em 2 g. Foram efetuadas as caracterizações física e química do gasóleo, polietileno pós-uso e do catalisador. Como resultado, obteve-se a produção de 87% de fração de óleo diesel em duas condições diferentes: (a) 550 0C de temperatura sem catalisador; (b) 500 0C de temperatura e 25% de catalisador FCC. Em ambos
os casos, a quantidade de gasóleo pesado e PEAD foram constantes (2 g Gasóleo; 0,2 g PEAD), assim com o tempo de reação de 15 minutos. A fração de óleo diesel obtida neste
estudo alcançou o poder calorífico de 44,0 MJ/Kg que é similar ao óleo diesel comercial. É importante ressaltar que em ambos os casos nenhum resíduo foi produzido, sendo uma rota
ambientalmente importante para reciclagem de embalagens plásticas contaminadas com óleo lubrificante originárias de postos de serviço, visando à recuperação de ambos conteúdo
energético e orgânico dos resíduos de embalagens plásticas pós-uso / In this work it was studied the co-pyrolysis process applied to HDPE plastic package with motor oil residues with Heavy Gas Oil and FCC Catalyst. The main objective of this work was to find the experimental conditions that enhanced the diesel fuel fraction in the pyrolitic oil. Factorial Design Methodology (FDM) was developed to enhance diesel fuel fraction (C9-C23) from waste high-density polyethylene (HDPE) and heavy gas oil (HGO) through copyrolysis. FDM was used for optimization of the following reaction parameters: temperature, catalyst and HDPE amounts. The HGO amount was constant (2.0 g) in all experiments. The model optimum conditions were determined to be temperature of 550 C, HDPE = 0.20 g and no FCC catalyst. Under such conditions, 94% of pyrolytic oil was recovered, of which diesel fuel fraction was 93% (87% diesel fuel fraction yield), no residue was produced and 6% of
noncondensable gaseous/volatile fraction was obtained. Seeking to reduce the cost due to high process temperatures, the impact of using higher catalyst content (25 %) with a lower temperature (500 C) was investigated. Under these conditions, 88% of pyrolytic oil was recovered (diesel fuel fraction yield was also 87%) as well as 12% of the noncondensable gaseous/volatile fraction. No waste was produced in these conditions, being an environmentally friendly approach for recycling the waste plastic. The diesel fuel fraction obtained in this study achieved heating value (44.0 MJ/Kg) similar to commercial diesel oil. This paper demonstrated the usefulness of using FDM to predict and to optimize diesel fuel fraction yield with a great reduction in the number of experiments. Based on experimental results, co-pyrolysis can represent a significant role in future in the recovery of both energetic and organic content of HDPE plastic package with motor oil residues
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Otimização da co-pirólise de gasóleo pesado com embalagens de PEAD pós-uso utilizando planejamento fatorial / Optimization co-pyrolysys from HDPE and heavy gas oil using factorial design methodologyNey Joppert Junior 07 January 2015 (has links)
A co-pirólise é uma rota promissora, uma vez que minimiza o impacto ambiental causado pela disposição do plástico de maneira inadequada, evita seu acúmulo em lixões e permite um melhor aproveitamento de um recurso natural não-renovável, o petróleo, matéria prima importante para a geração de energia e obtenção de produtos químicos. O presente trabalho teve como objetivo a definição das condições experimentais mais propícias à obtenção de líquidos pirolíticos com alta fração de óleo diesel, resultantes da co-pirólise de polietileno de alta densidade (PEAD) pós-consumo com gasóleo pesado tilizando-se catalisador de FCC (Fluid Catalytic Cracking). Como instrumento de otimização das condições experimentais, optou-se pela Metodologia Planejamento Fatorial. Foi também
estudado o efeito das condições experimentais, como: a temperatura de reação, a relação gasóleo/polietileno e a quantidade de catalisador no meio reacional. As amostras de
polietileno, gasóleo e catalisador foram submetidas à co-pirólise em sistema de leito fixo, sob fluxo constante de nitrogênio, variando-se a temperatura entre 450 C a 550 C, a quantidade de PEAD no meio reacional foi de 0,2 a 0,6 g, e a quantidade de catalisador foi de zero a 0,06 g, mantendo-se fixa a quantidade de gasóleo em 2 g. Foram efetuadas as caracterizações física e química do gasóleo, polietileno pós-uso e do catalisador. Como resultado, obteve-se a produção de 87% de fração de óleo diesel em duas condições diferentes: (a) 550 0C de temperatura sem catalisador; (b) 500 0C de temperatura e 25% de catalisador FCC. Em ambos
os casos, a quantidade de gasóleo pesado e PEAD foram constantes (2 g Gasóleo; 0,2 g PEAD), assim com o tempo de reação de 15 minutos. A fração de óleo diesel obtida neste
estudo alcançou o poder calorífico de 44,0 MJ/Kg que é similar ao óleo diesel comercial. É importante ressaltar que em ambos os casos nenhum resíduo foi produzido, sendo uma rota
ambientalmente importante para reciclagem de embalagens plásticas contaminadas com óleo lubrificante originárias de postos de serviço, visando à recuperação de ambos conteúdo
energético e orgânico dos resíduos de embalagens plásticas pós-uso / In this work it was studied the co-pyrolysis process applied to HDPE plastic package with motor oil residues with Heavy Gas Oil and FCC Catalyst. The main objective of this work was to find the experimental conditions that enhanced the diesel fuel fraction in the pyrolitic oil. Factorial Design Methodology (FDM) was developed to enhance diesel fuel fraction (C9-C23) from waste high-density polyethylene (HDPE) and heavy gas oil (HGO) through copyrolysis. FDM was used for optimization of the following reaction parameters: temperature, catalyst and HDPE amounts. The HGO amount was constant (2.0 g) in all experiments. The model optimum conditions were determined to be temperature of 550 C, HDPE = 0.20 g and no FCC catalyst. Under such conditions, 94% of pyrolytic oil was recovered, of which diesel fuel fraction was 93% (87% diesel fuel fraction yield), no residue was produced and 6% of
noncondensable gaseous/volatile fraction was obtained. Seeking to reduce the cost due to high process temperatures, the impact of using higher catalyst content (25 %) with a lower temperature (500 C) was investigated. Under these conditions, 88% of pyrolytic oil was recovered (diesel fuel fraction yield was also 87%) as well as 12% of the noncondensable gaseous/volatile fraction. No waste was produced in these conditions, being an environmentally friendly approach for recycling the waste plastic. The diesel fuel fraction obtained in this study achieved heating value (44.0 MJ/Kg) similar to commercial diesel oil. This paper demonstrated the usefulness of using FDM to predict and to optimize diesel fuel fraction yield with a great reduction in the number of experiments. Based on experimental results, co-pyrolysis can represent a significant role in future in the recovery of both energetic and organic content of HDPE plastic package with motor oil residues
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