The purpose of this work is to develop a reliable procedure for determination of liquid phase heats of adsorption via a flow calorimetric technique. The second objective is to study heats of adsorption of target sulfur compounds on potential desulfurization sorbents. Thirdly, we strive to relate the data obtained to the properties of both the sorbent and sorbates studied. Finally, the ultimate goal of this research is to use the data obtained to develop a high capacity selective adsorbent for the desulfurization of diesel fuel. Liquid phase flow adsorption experiments were conducted on sodium-Y zeolite (NaY), nickel exchanged NaY zeolite (NiY) and cesium-exchanged NaY zeolite (CsY). The solutions used in calorimetric experiments included naphthalene in n-hexadecane (C16), dibenzothiophene (DBT) in C16, and quinoline in C16. These solutions were used to model the adsorption of aromatic, sulphur-containing and nitrogen-containing compounds in diesel fuel, respectively. Additional experiments were conducted using equimolar concentrations of all three species in C16 to examine competitive adsorption behaviour of the mixture. During heat flow experiments, effluent samples were collected and analysed to obtain breakthrough curves for the systems. Heat of adsorption data were obtained via flow microcalorimetry using a novel procedure developed by this group. In this study, some experiments were conducted to examine the repeatability and utility of this new method. Characterization experiments were also conducted including BET surface area analysis, X-Ray diffraction (XRD) analysis and Inductively Coupled Plasma – Optical Emission Spectroscopy (ICP-OES) analysis to determine the properties of the sorbents. These properties were then related to data obtained in flow adsorption calorimeter experiments. A detailed discussion on the development of a novel method for determination of liquid phase heats of adsorption is presented. Analysis of calculation results using this new method show good repeatability relative to the previous method used. Equilibrium adsorption relationships are developed using the Langmuir adsorption model, and these results are compared to flow adsorption results obtained from the calorimeter. Results indicate that in terms of desulfurization capability, NaY appeared to be the best sorbent. Heats of adsorption were only moderate on NaY, indicating that regeneration of the sorbent would not be difficult, and NaY had the highest sulfur capacity of the sorbents studied. This result was not in agreement with literature results, and it is proposed that the discrepancy is the result of disruption of the crystalline structure of our sorbents during the modification process. Recommendations are presented for ongoing work, including important calorimeter experiments, modifications for improvement of experimental procedure and apparatus, additional sorbent characterization for elucidation of adsorption mechanisms, and finally experiments for verification and further validation of our innovative experimental technique.

The aim of this research was mainly to investigate desulfurization behaviour of ladle furnace slags of a low-sulfur steel. First, the change of the amount of unstable oxides (FetO and MnO) in slags was studied from the converter till the end of ladle furnace treatment for different steel quality groups. It was found that the change in the amount of unstable oxides could be examined best with low-C steel qualities. Then, the change of activity of iron oxide was investigated for a member of low-C steel quality group, namely 4937K, a low-S steel. The relation between the degree of desulfurization at the ladle furnace, % DeS (measured), and the change in activity of iron oxide, % Decrease in aFetO, was examined first using an empirical expression obtained from literature. Then, this relationship was studied using steel oxygen activity measurements conducted at the ladle furnace. With this method, a regression formula was proposed for 4937K slags relating activity coefficient of iron oxide, gama(FetO), with the major slag components. The results obtained from steel oxygen activities were found to be representative for 4937K steel-slag system showing similar behaviour with the ones from the empirical expression obtained from literature. Similar results were found using Temkin equation and the polymeric anion model. In relation to formation of less harmful inclusions to suppress adverse effects of sulfur, morphological studies of some steels produced in ERDEMiR plant were performed. D-type globular inclusions with severity values of 1-2 were observed.

No description available.

Thesis (MTech. degree in Mechanical Engineering)--Tshwane University of Technology, 2009. / South Africa produces 41.3 GWe per year of which 90% is coal-derived. During combustion of coal, sulfur contained in the fuel is converted to SO2. The gas poses a serious danger for the human and environmental health. The health hazards associated with SO2 include hair loss, throat inflammation, impaired vision and respiratory illnesses. Sulfur dioxide is also forms acid rain, which leads to acidification of soils, waterways and forests. The main objective of this investigation is to explore methods of increasing lime utilization using South Africa calcium/siliceous-based sorbents for the purposes of removal of SO2 in the Flue Gas Desulfurization (FGD) system. Consequently, this study presents experimental findings on the preparation, characterization and sulfation of locally available fly ash, calcium oxide (CaO) and bottom ash. CaO was obtained from calcination of limestone in a laboratory kiln at a temperature of 900 °C and CaO/fly ash sorbent prepared using an atmospheric hydration process.

No description available.

Thesis (Ph.D.)--University of Tulsa, 1990. / Bibliography: leaves 125-132.

xviii, 242 p. : ill. (some col.) / Fuel purification is an extremely active area of research in today's green world. Specifically, desulfurization of fuels is an important area of research for two reasons. First, any sulfur present in fuels generates SOx pollutants that are hazardous to human health and also contribute to acid rain. Secondly, even trace sulfur contaminants prohibit the use of fuel streams in fuel cells. However, achieving near-zero sulfur levels with existing technology is impractical. The work in this thesis investigates a new process for the removal of sulfur from fuel streams using a film-shear reactor (based on a process known as oxidative desulfurization), and goes on to investigate the mode of activation for the process within the reactor through a study of the reactor conditions. Additionally, other applications of the film-shear reactor, including mechanical activation of molecules and controlled nanoparticle synthesis are explored. Chapter I outlines the current status of oxidative desulfurization research, highlighting the strengths of the method, innovative approaches and drawbacks to the various approaches. Chapters II and III go on to discuss the enhancement of the process in the film-shear reactor using model fuels and a variety of substrates. This method was found to significantly enhance the oxidative desulfurization process, reducing both the time and temperature required to achieve considerable sulfur removal. Levels of desulfurization that require hours at elevated temperatures by conventional stirring methods were obtainable on the scale of seconds at or below room temperature. Chapter IV offers investigations into the conditions within the film-shear reactor, and also presents studies of the ability of the high shear rates obtained in the reactor to mechanically activate molecules. Chapter V extends the applicability of the film-shear reactor to nanoparticle synthesis through investigation of two titania synthesis methods utilizing the film-shear reactor. Appendices A and B offer supplementary information to enhance the studies presented in Chapters II and III, while Appendices C, D, and E highlight work done investigating the ability of platinum complexes to hydrate nitriles and cyanohydrins. This dissertation includes previously published and unpublished co-authored material. / Committee in charge: Victoria J. DeRose, Chairperson; David R. Tyler, Advisor; Kenneth M. Doxsee, Member; Catherine J. Page, Member; Mark H. Reed, Outside Member

A siderurgia vem sofrendo transformações que buscam inovação e matérias-primas alternativas. Dentro deste contexto, o uso de resíduos industriais para a formação de escórias sintéticas é tido como alternativa na busca de novos materiais e rotas de reaproveitamento de resíduos. Portanto, este trabalho teve como objetivo estudar o uso de escórias sintéticas na etapa de dessulfuração do ferro-gusa, aço e ferro fundido. Assim como, propor a utilização da sodalita e da alumina em substituição à fluorita e o resíduo de mármore em substituição à cal convencional. Inicialmente, o resíduo foi caracterizado utilizando as seguintes técnicas: análise química, análise granulométrica, área de superfície específica, difração de raios-X, microscopia eletrônica de varredura (MEV) e análise de espectroscopia por energia dispersiva (EDS). Os resultados da caracterização mostraram que aproximadamente 90% das partículas do resíduo de mármore estão abaixo de 100m e sua área superficial foi de 0,24m²/g. Através da difração de raios-X foi observado que o resíduo é composto por CaCO3, MgCO3 e SiO2. Na sequência, foram feitas simulações com o software Thermo-Calc para obter dados termodinâmicos das fases presentes nas misturas e compará-los com os resultados experimentais. Além disso, também foram calculados dados de capacidade de sulfeto (Cs), partição de enxofre (Ls) e basicidade ótica () das misturas iniciais. Posteriormente, foram realizados os ensaios experimentais em escala laboratorial para ferro-gusa, ferro fundido e aço, respectivamente nas temperaturas de 1400°C, 1550°C e 1600°C. Nos ensaios de dessulfuração do aço e do ferro-gusa, utilizou-se um rotor de alumina com o objetivo de favorecer a agitação no metal e aumentar a remoção de enxofre. Na etapa de dessulfuração do ferro-gusa, constatou-se que a fase sólida de CaO é a responsável pela remoção de enxofre e que a presença das fases silicato tricálcio e aluminato tricálcio (3CaO.SiO2 e 3CaO.Al2O3) limitam a reação, sendo maiores suas concentrações nas escórias que utilizaram o resíduo de mármore e sodalita, devido a presença de SiO2 e Al2O3 nestas matérias-primas. Já para o aço e o ferro fundido, que foram estudados com escórias à base de CaO e Al2O3, observou-se que o aumento da fase líquida favoreceu a dessulfuração. Verificou-se que a dessulfuração no ferro fundido foi por escória de topo e no aço por um processo misto, onde a fase líquida e fase sólida participaram da dessulfuração. / The steel industry is going through transformations aiming at innovation and use of alternative raw materials. In this context, the use of industrial waste in the production of synthetic slag is considered an important option on the search for new materials and waste reuse. Therefore, the aim of this work was to study the use of synthetic slags at the desulfurization of hot metal, steel and cast iron. It was proposed the use sodalite and alumina instead of fluorite and the use of marble waste instead of lime. Marble waste was characterized by chemical analysis, particle size analysis, specific surface area, X-ray diffraction (XRD), scanning electron microscopy (SEM), analysis with energy dispersive spectroscopy (EDS). The characterization results showed that almost 90% of the particles are smaller than 100 m and its specific surface area was 0.2406m²/g. The XRD has showed the presence of compounds such as CaCO3 and MgCO3 and SiO2. Further, simulations using Thermo-Calc were performed in order to obtain thermodynamic data of the present phases, and to compare with experimental data. Furthermore, sulfide capacity (Cs), sulfur partition (Ls) and optical basicity () were determined. The experimental procedures were carried out at 1400°C, 1550°C and 1600°C for hot metal, cast iron and steel, respectively. In addition, steel and hot metal tests were performed using an alumina rotor to raise the desulphurization. In hot metal desulphurization, solid CaO phase was responsible for sulfur removal. Furthermore, 3CaO.SiO2 and 3CaO.Al2O3 phases limited the reaction, being their concentration higher in the slags with marble waste and sodalite, due to the presence of SiO2 and Al2O3 in these raw materials. Slags composed mainly of CaO and Al2O3 were used in steel and cast iron desulphurization. It was observed that when increasing liquid phase, the reaction of desulphurization was favored. Besides, it was found that cast iron desulfurization occurs by top slag mechanism and steel desulfurization by a mixed process where the liquid phase and solid phase have influence on the desulfurization.

Yes / Catalysts play a vital role in petroleum and chemical reactions. Intensified concerns for cleaner air with strict environmental regulations on sulfur content in addition to meet economic requirements have generated significant interests for the development of more efficient and innovative oxidative catalysts recently. In this study, a novel homemade nano catalyst (manganese oxide (MnO2) over tin (IV) oxide (SnO2)) was used for the first time as an effective catalyst in removing dibenzothiophene (DBT) from kerosene fuel using hydrogen peroxide (H2O2) as oxidant in catalytic oxidative-extractive desulfurization process (OEDS). The catalyst was prepared by impregnation method with various amount of MnO2 loaded on SnO2. The oxidation step was carried out at different operating parameters such as reaction temperature and reaction time in batch reactor. The extractive desulfurization step was performed by using acetonitrile as solvent under several operating conditions (agitation speed and mixing time). The activity of MnO2/SnO2 catalyst in removing various sulfur compounds from kerosene fuel at the best operating conditions was investigated in this work. The results of the catalyst characterization proved that a high dispersion of MnO2 over the SnO2 was obtained. The experiments showed that the highest DBT and various sulfur compounds removal efficiency from kerosene fuel under the best operating conditions (oxidation: 5% MnO2/SnO2, reaction temperature of 75 0C, and reaction time of 100 min, extraction: acetonitrile, agitation speed of 900 rpm, and mixing time of 30 min) via the catalytic oxidative-extractive desulfurization process was 92.4% and 91.2%, respectively. Also, the MnO2/SnO2 catalyst activity was studied after six consecutive oxidation cycles at the best operating conditions, and the catalyst prove satisfactory stability in terms of sulfur compounds removal. After that, the spent catalyst were regenerated by utilizing different solvents (methanol, ethanol and iso-octane), and the experimental data explained that iso-octane achieved highest regeneration efficiency. / This study was supported by College of Petroleum Processes Engineering, Tikrit University, Iraq and Ministry of Oil, Iraq.

Yes / This study was focused on developing a new catalyst using metal oxide (10 %Mn) over Nano- activated Carbon (Nano-AC) particles and designing a new reactor (digital basket reactor, DBR) for the sulfur removal from kerosene oil via oxidative desulfurization (ODS). The new homemade Nano-catalyst was prepared by utilizing impregnation process and was characterized by SEM, EDX, BET, and FTIR techniques. The performance of ODS process under moderate operating conditions was significantly enhanced by the application of the new catalyst and the new reactor. The results showed that 94 % of the sulfur could be achieved at oxidation temperature of 80 ºC, oxidation time of 35 min and agitation rate of 750 rpm. The reactivity of catalyst was examined after four consecutive ODS cycles under the optimal experimental parameters and the used catalyst showed excellent stability based on oxidation efficiency. The spent catalyst was treated by methanol, ethanol and iso-octane solvents for regenerated it, and the result proved that iso-octane carried out the maximum regeneration performance. An optimization method depending on minimizing the sum of the squared error among the experimental and model predicted data of ODS technology was employed to evaluate the optimal kinetic model parameters of the reaction system. The ODS process model was able to predict the results obtained experimentally for a wide range of conditions very well by absolute average errors<5 %.