Yes / A digital baffle batch reactor (DBBR) for oxidative desulfurization (ODS) reactions is designed and applied here in order to reduce the sulfur concentration presented in light gas oil (LGO) based on a novel homemade nano-catalyst (Copper Oxide (CuO)/Activated Carbon (AC)). With efficient impregnation, good pore size distribution, high activity and higher surface area, the designed nano-catalyst (CuO/AC) demonstrated excellent catalytic efficiency. To evaluate the effectiveness of nano catalyst (prepared experimentally), several experiments related to ODS reactions using the digital baffle batch reactor are carried out under moderate process conditions (reaction temperature (100, 120 and 140 °C), contact time (15, 30 and 45 min) and oxidant (H2O2) amount (2, 3 and 5 ml)). The experimental outcomes indicated that increasing the reaction temperature, batch time and oxidant amount lead to reduced sulfur concentration of oil feedstock leading to a greener fuel. The efficiency of sulfur conversion is reported to be 83.1 % using the modified nano-catalysts and new reactor (DBBR) at reaction temperature 140 oC, batch time 45 min and H2O2 amount of 5 ml. So, such new results using DBBR for ODS reactions based on CuO/AC as a new modified nano catalyst has not been reported in the public domain and it is considered as new results.

Growing environmental concerns, such as global warming, are giving rise to new regulations imposed by the International Maritime Organization (IMO) on sulfur content for marine fuels, thus, constraining refining processes. Oxidative desulfurization (ODS) is an appealing desulfurization method with some advantages over traditional processes like hydrodesulfurization (HDS), such as mild operating conditions and no-hydrogen consumption. ODS could be employed as a complementary or alternative process for HDS. During the oxidative desulfurization, the organo-sulfur compounds are oxidized to polar sulfones. Then, such sulfones are separated from the treated fuel oil using techniques such as liquid-liquid extraction. In the present work, the separation of oxidized sulfur-containing compounds of heavy fuel oil using ultrasound-assisted technology has been investigated and simulated in Aspen Plus. The oxidant selected was hydrogen peroxide, while the catalyst was acetic acid. The chosen solvent for the sulfone separation was acetonitrile. The primary goal of this work is to successfully emulate the operation performed by an oxidative desulfurization pilot plant-scale apparatus designed by Tecnoveritas®, which will later allow the analysis of the parameters on the overall sulfur removal efficiency.

Yes / Batch oxidative desulfurization (ODS) process is investigated here for the removal sulfur compound from light naphtha using homemade new nano-catalyst. The catalyst is made of manganese dioxide supported on zeolite nanoparticles which shows an excellent catalytic performance with good impregnation, high activity, good pore size distribution and larger surface area. Different reaction temperature, time and initial sulfur concentration are used to have a deeper insight of the process. The experimental results reveal that the conversion of sulfur compound is increased by increasing the initial sulfur concentration, the reaction temperature and batch time. A mathematical model of the process is developed and validated using the experimental data within gPROMS software with high accuracy. The validated model (errors less than 5% between experimental and predicted results) is then utilized to obtain the optimal operation conditions of the process giving maximum conversion of sulfur (higher than 99%) resulting in an environmentally friendly fuel.

Yes / In this work, the performance of oxidative desulfurization (ODS) of dibenzothiophene (DBT) in light gas oil (LGO) is evaluated with a homemade manganese oxide (MnO2/γ-Al2O3) catalyst. The catalyst is prepared by Incipient Wetness Impregnation (IWI) method with air under moderate operating conditions. The effect of different reaction parameters such as reaction temperature, liquid hour space velocity and initial concentration of DBT are also investigated experimentally. Developing a detailed and a validated trickle bed reactor (TBR) process model that can be employed for design and optimization of the ODS process, it is important to develop kinetic models for the relevant reactions with high accuracy. Best kinetic model for the ODS process taking into account hydrodynamic factors (mainly, catalyst effectiveness factor, catalyst wetting efficiency and internal diffusion) and the physical properties affecting the oxidation process is developed utilizing data from pilot plant experiments. An optimization technique based upon the minimization of the sum of the squared error between the experimental and predicted composition of oxidation process is used to determine the best parameters of the kinetic models. The predicted product conversion showed very good agreement with the experimental data for a wide range of the operating condition with absolute average errors less than 5%.

Made available in DSpace on 2014-12-17T15:42:00Z (GMT). No. of bitstreams: 1 Mariele ISM_DISSERT.pdf: 4704397 bytes, checksum: 9fa1538bc3d6948d492f9a6c378eaf62 (MD5) Previous issue date: 2012-07-20 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The oxidative desulfurization process (ODS) of a commercial diesel fuel was performed under mild conditions in the presence of catalysts based on vanadium or manganese, supported on alumina, clays (commercial, natural and pillared) and zeolites (NaX, NaY, beta, mordenite and ZSM-5). The catalysts were synthesized by wet impregnation and characterized by X-ray diffraction, textural analysis by N2 adsorption and scanning electron microscopy. The dibenzothiophene (DBT) was used as sulfur compound in catalytic evaluation. The reactions were performed using acetonitrile as solvent and the hydrogen peroxide as oxidant at 55?C. The reaction products were analized by gas chromatography (GC-FID). In the studied conditions, the process was efficient due to the DBT was converted to its corresponding sulfone. Both DBT and corresponding sulfone were extracted by the solvent. Removals and oxidations up to 100% of sulfur compound were achieved. The catalysts supported on ZSM-5 zeolite showed are more effective for oxidation reaction of sulfur compound, presenting the best results. It was observed for oxidation reaction, that vanadium catalysts were more effective and manganese catalysts showed best results for removal of sulfur compounds / O processo de Dessulfuriza??o Oxidativa (ODS) de um diesel comercial foi realizado em condi??es suaves na presen?a de catalisadores ? base de van?dio ou mangan?s, suportados em aluminas, argilas (comerciais, naturais e pilarizadas) e ze?litas (NaX, NaY, beta, mordenita, ZSM-5). Os catalisadores foram sintetizados via impregna??o ?mida e caracterizados por difra??o de raios-X, an?lise textural por adsor??o e dessor??o de nitrog?nio e microscopia eletr?nica de varredura. O dibenzotiofeno (DBT) foi utilizado como o composto de enxofre nos testes catal?ticos. As rea??es foram realizadas usando como solvente acetonitrila e como oxidante o per?xido de hidrog?nio a temperatura de 55?C. Os produtos de rea??o foram analisados por cromatografia gasosa (CG-FID). Nas condi??es estudadas o processo mostrouse eficiente, o DBT foi convertido para sua respectiva sulfona. Ambos DBT e a sulfona foram extra?dos pelo solvente. Remo??es e oxida??es de 100% do composto de enxofre foram alcan?adas. Os catalisadores suportados na ze?lita ZSM-5 mostraram-se mais efetivos para a rea??o de oxida??o do composto sulfurado, apresentando os melhores resultados. Observa-se para a rea??o de oxida??o que os catalisadores de van?dio foram mais efetivos, e os catalisadores de mangan?s apresentaram melhores resultados na extra??o dos compostos sulfurados