Download or read book The Performance of Structured Cobalt Catalysts in Fischer Tropsch Synthesis written by Youqi Zhuang and published by . This book was released on 2009 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Iron and Cobalt Catalysts written by Wilson D. Shafer and published by MDPI. This book was released on 2020-06-23 with total page 414 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since the turn of the last century when the field of catalysis was born, iron and cobalt have been key players in numerous catalysis processes. These metals, due to their ability to activate CO and CH, haev a major economic impact worldwide. Several industrial processes and synthetic routes use these metals: biomass-to-liquids (BTL), coal-to-liquids (CTL), natural gas-to-liquids (GTL), water-gas-shift, alcohol synthesis, alcohol steam reforming, polymerization processes, cross-coupling reactions, and photocatalyst activated reactions. A vast number of materials are produced from these processes, including oil, lubricants, waxes, diesel and jet fuels, hydrogen (e.g., fuel cell applications), gasoline, rubbers, plastics, alcohols, pharmaceuticals, agrochemicals, feed-stock chemicals, and other alternative materials. However, given the true complexities of the variables involved in these processes, many key mechanistic issues are still not fully defined or understood. This Special Issue of Catalysis will be a collaborative effort to combine current catalysis research on these metals from experimental and theoretical perspectives on both heterogeneous and homogeneous catalysts. We welcome contributions from the catalysis community on catalyst characterization, kinetics, reaction mechanism, reactor development, theoretical modeling, and surface science.
Download or read book Effect of Different Mesostructured Material Based on Silica TiO2 SBA 15 and CAB O SIL as Cobalt Supports for Fischer tropsch Synthesis written by Mohamad Irsyad Mohamad Mazuki and published by . This book was released on 2012 with total page 43 pages. Available in PDF, EPUB and Kindle. Book excerpt: The research was about the synthesis of active and selective for syngas processing via Fischer-Tropsch synthesis (FTS) producing clean and best fuel. A series of 20 wt. % cobalt catalysts be prepared by impregnation of a mesoporous molecular sieve based on silica as 75 wt. % of cobalt catalytic supporters (SBA-15, TiO and CabO-Sil) with 5 wt. % Zn promoter for comparison purposes. All materials used characterizing by several analysis equipments which are SEM, TGA and FTIR. The characterization results achieve gave a great influence of mesoporous support porosity on the structure, reducibility of cobalt oxide species supported over the selected materials. Firstly, the experiment was started from the synthesis of SBA-15. TiO2 and Cab-O-Sil are commercialized support. Then, the silica as cobalt supporters were synthesized by incipient wetness impregnation method of using mixture of Cobalt (II) Nitrate and Zinc Nitrate Hexahydrate solution. Next, the prepared catalysts were calcined at 350°C for 6 h by increasing the temperature at a controlled heating rate of 2°C/min. The characterization of catalysts and catalyst studies was performed. The result from experiment was SBA-15 supporter shown the better result compared to other samples as the microscopic size captured by SEM equipment prove that SBA-15 had smoothest and smallest of mesoporous surface size. The result from FTIR showed that the peak at around 3,440 cm-1 have the hydroxyl groups and about 1,630 cm -12 is due to the bending vibrations of O-H bonds that the percentage reflectance of O-H bonds which indicates the SBA-15 can effectively restrain the loss of surface hydroxyl groups during calcinations. The peak around 1000-1200 cm1 can be assigned to the siloxane or Si-O-Si stretching bands; peak appears as a broad and strong peaking the sample. Lastly, TGA result showed that SBA-15 can help the catalyst samples restrained more water content in the evaporation process and had high thermal stability that can prolong life at high temperature and high pressure in the Fischer-Tropsch synthesis. The new silica as cobalt supporter will be developed to enhance the performance of the best and clean fuel production. This research hopefully can be carried out successful in order to get the new invention for production of catalyst that will produce the best and clean fuel and to get rid of exceed cost of production but in the same quality of expensive product.
Download or read book Fischer Tropsch Technology written by André Steynberg and published by Elsevier. This book was released on 2004-10-30 with total page 722 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fischer-Tropsch Technology is a unique book for its state-of-the-art approach to Fischer Tropsch (FT) technology. This book provides an explanation of the basic principles and terminology that are required to understand the application of FT technology. It also contains comprehensive references to patents and previous publications. As the first publication to focus on theory and application, it is a contemporary reference source for students studying chemistry and chemical engineering. Researchers and engineers active in the development of FT technology will also find this book an invaluable source of information. * Is the first publication to cover the theory and application for modern Fischer Tropsch technology * Contains comprehensive knowledge on all aspects relevant to the application of Fischer Tropsch technology* No other publication looks at past, present and future applications
Download or read book Structured Catalysts and Reactors written by Andrzej Cybulski and published by CRC Press. This book was released on 2005-11-02 with total page 828 pages. Available in PDF, EPUB and Kindle. Book excerpt: Interest in structured catalysts is steadily increasing due to the already proven, as well as potential, advantages of these catalysts. Updating the comprehensive coverage of the first edition published in 1998 with the latest science and applications, Structured Catalysts and Reactors, Second Edition gives detailed information on all aspect
Download or read book Fischer Tropsch Synthesis Catalysts and Catalysis written by Burtron H. Davis and published by CRC Press. This book was released on 2016-04-06 with total page 424 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is based on a symposium held during the 248th American Chemical Society meeting that focused on use of the Fischer-Tropsch process in producing synthetic fuels. Its contents reflect the four dominant subjects of the meeting: catalyst preparation and activation, catalyst activity and reaction mechanisms, catalyst characterization and related reactions, and topics concerning commercializing the Fischer-Tropsch process. It covers recent developments related to renewable resources and green energy and provides a glimpse of the commercial potential of the Fischer-Tropsch process in synthetic fuel production.
Download or read book Advances in Fischer Tropsch Synthesis Catalysts and Catalysis written by B. H. Davis and published by CRC Press. This book was released on 2009-11-10 with total page 430 pages. Available in PDF, EPUB and Kindle. Book excerpt: Rising oil costs have stimulated significant interest in the Fischer-Tropsch synthesis (FTS) as a method for producing a synthetic petroleum substitute. Drawn from the proceedings at a symposium held during the 236th meeting of the American Chemical Society in Philadelphia in August 2008, Advances in Fischer-Tropsch Synthesis, Catalysts, and Cataly
Download or read book Fischer Tropsch Refining written by Arno de Klerk and published by John Wiley & Sons. This book was released on 2012-12-21 with total page 661 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Fischer-Tropsch process is gaining recognition again due to the world-wide increase in energy needs and decrease in oil availability. The increasing interest in utilizing biomass as a potential renewable feedstock in energy generation is further supporting this development. The book covers the production and refining of Fischer-Tropsch syncrude to fuels and chemicals systematically and comprehensively, presenting a wealth of new knowledge and material. As such, it deals extensively with aspects of engineering, chemistry and catalysis. This handbook and ready reference adopts a fundamental approach, looking at the molecules and their transformation from feed to product. Numerous examples illustrate the possibilities and limitations of Fischer-Tropsch syncrude as feesdstock. Of great interest to everyone interested in refining - not just Fischer-Tropsch specialists. From the Contents: Fischer-Tropsch Facilities and Refineries at a Glance Production of Fischer-Tropsch Syncrude Industrial Fischer-Tropsch Facilities Synthetic Transportation Fuels Refining Technology Refinery Design
Download or read book Morphological Compositional and Shape Control of Materials for Catalysis written by Paolo Fornasiero and published by Elsevier. This book was released on 2017-05-23 with total page 712 pages. Available in PDF, EPUB and Kindle. Book excerpt: Morphological, Compositional, and Shape Control of Materials for Catalysis, Volume 177, the latest in the Studies in Surface Science and Catalysis series, documents the fast-growing developments in the synthesis, characterization, and utilization of nanostructures for catalysis. The book provides essential background on using well-defined materials for catalysis and presents exciting new paradigms in the preparation and application of catalytic materials, with an emphasis on how structure determines catalytic properties. In addition, the book uniquely features discussions on the future of the field, with ample space for future directions detailed in each chapter. - Presents the latest paradigms in the preparation and application of catalytic materials - Provides essential background on using well-defined materials for catalysis - Features discussion of future directions at the end of each chapter
Download or read book Catalysis in the Refining of Fischer Tropsch Syncrude written by Arno de Klerk and published by Royal Society of Chemistry. This book was released on 2010 with total page 295 pages. Available in PDF, EPUB and Kindle. Book excerpt: The first book to provide a review of the literature on the catalysis needed to refine syncrude to transportation fuels.
Download or read book The Fischer Tropsch Reaction Over Ti Modified Cobalt Catalysts written by Andrew Ronald Raub and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation presents research done to investigate the promoter effects of small amounts of titanium oxides (TiOx) on unsupported cobalt metal catalysts for the atmospheric pressure Fischer-Tropsch (CO+H2) reaction. It is known that cobalt catalysts with TiO2 supports can have their performance for the Fischer-Tropsch reaction enhanced due to interactions between cobalt metal and the support. Small TiOx species can migrate onto the surface of metal particles during reductive treatment, termed the "strong metal-support interaction" (SMSI). Interactions between TiOx species and the cobalt metal are expected to influence its catalytic behavior. Techniques were developed to create unsupported cobalt metal catalysts dosed with controlled amounts of TiOx via oxalate precursors. By eliminating the presence of a supporting material, interactions between cobalt metal and TiOx could be focused on. This is the first time that TiOx alone has been studied as a promoter species in controlled amounts over an unsupported cobalt catalyst for the atmospheric pressure CO+H2 reaction.Steady state and chemical transient kinetic (CTK) reaction studies revealed that very small amounts of Ti (~1-2 atom%, relative to cobalt) induce changes in the catalyst structure and product selectivity. The addition of TiOx to the cobalt resulted in increased selectivity toward alkenes and suppression of CH4 and C2H6 that persisted over long reaction times. When TiOx is present, CTK measurements revealed the presence of surface intermediates that are absent over pure cobalt and react with different kinetics to form chain lengthened hydrocarbons. Estimated carbon amounts on the catalyst surfaces showed ~3 carbon atoms/cobalt metal site for pure cobalt catalysts, and ~5-6 carbon atoms/cobalt metal site for Ti-modified cobalt catalysts. General observations made about formation and decay behavior for hydrocarbon products during CTK studies were in good agreement with those obtained for similar work done on CoMgO and CoMnOx catalysts. Suggestions for the direction of future work on Ti-modified cobalt catalysts are made at the end of this dissertation.Some effort has also been spent on using methyl formate, which can be considered a liquid form of syngas, to produce chain lengthened hydrocarbons using CoMnTi catalysts. This ternary catalyst composition was selected due to its industrial relevance. Some transient kinetic studies were performed but turned out challenging to interpret due to the complexity of parallel decomposition pathways for methyl formate. In view of the complexity of the CoMnTi catalyst composition, it was deemed important to first focus on the CoTi case as a prerequisite for studying more complicated catalyst formulations.
Download or read book Natural Gas Conversion V written by A. Parmaliana and published by Elsevier. This book was released on 1998-09-17 with total page 1005 pages. Available in PDF, EPUB and Kindle. Book excerpt: On January 1988, the ascertained and economically accessible reserves of Natural Gas (NG) amounted to over 144,000 billion cubic meters worldwide, corresponding to 124 billion tons of oil equivalents (comparable with the liquid oil reserves, which are estimated to be 138 billion TOE). It is hypothesized that the volume of NG reserve will continue to grow at the same rate of the last decade. Forecasts on production indicate a potential increase from about 2,000 billion cubic meters in 1990 to not more than 3,300 billion cubic meters in 2010, even in a high economic development scenario. NG consumption represents only one half of oil: 1.9 billion TOE/y as compared to 3.5 of oil. Consequently, in the future gas will exceed oil as a carbon atom source. In the future the potential for getting energetic vectors or petrochemicals from NG will continue to grow.The topics covered in Natural Gas Conversion V reflect the large global R&D effort to look for new and economic ways of NG exploitation. These range from the direct conversion of methane and light paraffins to the indirect conversion through synthesis gas to fuels and chemicals. Particularly underlined and visible are the technologies already commercially viable.These proceedings prove that mature and technologically feasible processes for natural gas conversion are already available and that new and improved catalytic approaches are currently developing, the validity and feasibility of which will soon be documented. This is an exciting area of modern catalysis, which will certainly open novel and rewarding perspectives for the chemical, energy and petrochemical industries.
Download or read book Hydrocarbon Chemistry written by George A. Olah and published by John Wiley & Sons. This book was released on 2003-09-10 with total page 897 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hydrocarbons and their transformations play major roles in chemistry as raw materials and sources of energy. Diminishing petroleum supplies, regulatory problems, and environmental concerns constantly challenge chemists to rethink and redesign the industrial applications of hydrocarbons. Written by Nobel Prize-winner George Olah and hydrocarbon expert Árpád Molnár, the completely revised and expanded Second Edition of Hydrocarbon Chemistry provides an unparalleled contemporary assessment of the field, presenting basic concepts, current research, and future applications. Hydrocarbon Chemistry begins by discussing the general aspects of hydrocarbons, the separation of hydrocarbons from natural sources, and the synthesis from C1 precursors with recent developments for possible future applications. Each successive chapter deals with a specific type of hydrocarbon transformation. The Second Edition includes a new section on the chemical reduction of carbon dioxide–focusing on catalytic, ionic, electrocatalytic, photocatalytic, and ezymatic reductions–as well as a new chapter on new catalysts and activation methods, combinatorial chemistry, and environmental chemistry. Other topics covered include: Major processes of the petrochemical industry, such as cracking, reforming, isomerization, and alkylation Derivation reactions to form carbon-heteroatom bonds Hydrocarbon oxidations Metathesis Oligomerization and polymerization of hydrocarbons All chapters have been updated by adding sections on recent developments to review new advances and results. Essential reading for practicing scientists in industry, polymer and catalytic chemists, as well as researchers and graduate students, Hydrocarbon Chemistry, Second Edition remains the benchmark text in its field.
Download or read book Bench scale Studies of the Fischer Tropsch Synthesis Over Iron Nickel and Nickel Cobalt Catalysts Japan written by Shiro Watanabe and published by . This book was released on 1951 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fischer Tropsch Synthesis written by and published by . This book was released on 2016 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: The effect of ammonia in syngas on the performance of various supported cobalt catalysts (i.e., Al2O3, TiO2 and SiO2) was investigated during Fischer-Tropsch synthesis (FTS) using a continuously stirred tank reactor (CSTR). The addition of ammonia (10 ppmv NH3) caused a significant deactivation for all supported cobalt catalysts, but the rate of deactivation was higher for the silica-supported catalysts relative to the alumina and titania-supported catalysts used in this work. Ammonia addition had a positive effect on product selectivity (i.e., lower light gas products and higher C5+) for alumina and titania-supported catalysts compared to ammonia free conditions, whereas, the addition of ammonia increased lighter hydrocarbon (C1-C4) products and decreased higher hydrocarbon (C5+) selectivity compared to ammonia-free synthesis conditions for the silica-supported catalyst. For alumina and titania-supported catalysts, the activity almost recovered with mild in-situ hydrogen treatment of the ammonia exposed catalysts. For the silica-supported catalyst, the loss of activity is somewhat irreversible (i.e., cannot be regained after the mild hydrogen treatment). Addition of ammonia led to a significant loss in BET surface area and changes in pore diameter (consistent with pore collapse of a fraction of pores into the microporous range as described in the literature), as well as formation of catalytically inactive cobalt support compounds for the silica-supported catalyst. On the other hand, the pore characteristics of alumina and titania-supported catalysts were not significantly changed. In conclusion, XANES results of the ammonia exposed silica-supported catalysts further confirm the formation of cobalt-support compounds (cobalt silicates).
Download or read book Metal Oxide Promotion of Cobalt Based Fischer Tropsch Synthesis Catalysts written by Gregory Robert Johnson and published by . This book was released on 2015 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt: Synthetic fuel production by means of Fischer-Tropsch synthesis (FTS) involves the catalytic hydrogenation of CO over Co-based catalysts. Often, these catalysts incorporate performance-enhancing additives known as promoters. Although not catalytically active for FTS by themselves, promoters can alter the structural and electronic properties of the active Co metal so as to improve catalyst activity, selectivity, or stability. Elements that form metal oxides have been studied for their ability to increase CO consumption rates and shift the product distribution toward higher molecular weight. Despite several decades of study of such elements, there remains limited understanding of the connections between these promotional effects and element properties. Accordingly, this dissertation focuses on clarifying the chemical basis for the effects of metal oxide promotion and making connections to periodic trends. To understand the importance of physical contact between the promoter and the Co, the influence of Co-Mn spatial association on the magnitude of Mn promotional effects was investigated. Elemental maps obtained by STEM-EDS revealed that different catalyst pretreatment methods could control how closely associated the promoter and Co were at the nanoscale. By relating these results to catalytic reaction data, it was determined that higher extents of contact between the two elements were correlated with higher selectivities toward C5+ hydrocarbons. This work was extended to the elements Ce, Gd, La, and Zr, which are among the most commonly studied metal oxide-forming promoters. The presence of the promoter element suppressed methane formation and increased the FTS chain propagation probability, but the sensitivity of these effects toward promoter loading was different for each element. Elements that deposited preferentially onto the Co nanoparticles led to rapid shifts in the product distribution as the promoter loading increased, whereas elements that dispersed over the entire catalyst surface resulted in more gradual changes. For all promoters, the product selectivities became insensitive to loading when the loading reached a quantity nearly equivalent to that which would form a half monolayer of the promoter on the Co nanoparticle surface. These trends are characteristic of the formation of active sites along the interface between the Co and the promoter that exhibit improved product selectivity. Structurally, the oxidation states and local coordination environments of the promoters were consistent with highly dispersed oxides. No evidence for the formation of bimetallic alloys or large promoter-containing crystallites was detected by either X-ray absorption spectroscopy or X-ray diffraction. These data suggest that small promoter oxide moieties decorate the surface of the Co metal nanoparticles so as to form metal-metal oxide interfaces. Under this model, the promotional effects increase in magnitude as the fraction of Co active sites that are adjacent to the promoter increases. When the Co surface is sufficiently covered by the promoter so that the fraction of active sites that are along the perimeter of the promoter moieties is nearly unity, the catalyst performance ceases to improve as a function of promoter loading. Guided by this reasoning, the catalytic properties of the promoted catalysts were investigated using samples in which the fraction of sites that were promoted was near unity. Measurements of reaction kinetics were conducted to assess the impact of metal oxide promotion on the rate parameters governing FTS. The rates of CO consumption for both unpromoted and metal oxide-promoted catalysts followed a Langmuir-Hinshelwood rate law for which H-assisted CO dissociation is assumed to be the rate determining step. Each promoter increased the apparent rate constant and the CO adsorption constant that appear within the rate law. Thus, metal oxide promotion appears both to facilitate the cleavage of the C-O bond and to enhance the extent of CO adsorption onto the catalyst. This finding was reinforced by CO temperature programmed desorption experiments and an evaluation of the effects of Mn promotion on the rate of CO disproportionation. Owing to the appearance of the CO adsorption constant in the numerator and denominator of the rate law, it is possible for promoted catalysts to have both higher and lower turnover frequencies than unpromoted catalysts depending on the chosen operating pressure. As a consequence, an optimal promoter can be found for maximizing the turnover frequency at a given operating pressure. However, product selectivity, which is largely determined by the availability of adsorbed H, is invariably improved by a higher CO adsorption constant because it decreases the ratio of adsorbed H to CO on the Co surface. Strong correlations between catalyst performance and the Lewis acidity of the promoter oxide suggest that Lewis acid-base interactions between the promoter and the adsorbed CO are the cause for the observed metal oxide promotional effects. Much of the experimental data presented in this work favors the hypothesis that CO can interact simultaneously with Co through the C atom and with the promoter cation through the O atom. These chemical interactions, in which the promoter serves as a Lewis acid, weaken the bond between C and O. Experimental evidence for this effect was observed in the lower activation barrier for CO hydrogenation over the ZrO2-promoted catalysts and the appearance of adsorbed carbonyl species on the MnO-promoted catalyst with severely redshifted C-O stretching frequencies measured by in situ infrared spectroscopy. These results provide insight into the chemical mechanism by which metal oxides affect the reaction and identify Lewis acidity of the promoter as the relevant descriptor for quantitatively predicting metal oxide-based promotional effects over Co FTS catalysts.
Download or read book Catalysis written by Ulf Hanefeld and published by John Wiley & Sons. This book was released on 2018-02-20 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt: Written by an excellent, highly experienced and motivated team of lecturers, this textbook is based on one of the most successful courses in catalysis and as such is tried-and-tested by generations of graduate and PhD students, i.e. the Catalysis-An-Integrated-Approach (CAIA) course organized by NIOK, the Dutch Catalysis research school. It covers all essential aspects of this important topic, including homogeneous, heterogeneous and biocatalysis, but also kinetics, catalyst characterization and preparation, reactor design and engineering. The perfect source of information for graduate and PhD students in chemistry and chemical engineering, as well as for scientists wanting to refresh their knowledge
