The Fischer-Tropsch (FT) synthesis is the catalytic conversion of hydrogen and carbon monoxide into higher hydrocarbons. Although ruthenium is the most active catalyst in FT synthesis, the lower cost metals iron and cobalt are used commercially. Generally, increased catalyst performance is achieved with increased metal surface area and dispersion, though recent literature reports that cobalt, iron and rhodium crystallites below a certain size in the nanometer range display lower metal surface area specific activity and a high methane selectivity. There have also been several attempts to investigate the possibility to conduct a homogeneously catalysed FT synthesis, which can be considered as an extreme case of metal dispersion. The aim of this study is to investigate FT activity and selectivity on well-defined nano-sized ruthenium crystallites and supported organometallic clusters with varying nuclearity, and to compare/bridge the obtained findings by subdividing it into a) catalyst preparation and characterisation, b) FT performance of model catalysts and c) theoretical investigations of the feasibility of FT reactions on ruthenium complexes.
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
The term gas-to-liquids refers to a small number of technologies designed to convert natural gas to liquid fuels, as alternatives to the traditional refining of crude oil and other natural gas commercialization routes. This work is a guideline on the theory of Process plant of GTL, i.e. the theory of synthesis gas production, Fischer-Tropsch synthesis and upgrading/refining. The plant is composed of process and mechanical equipment. Additionally, I considered the process plant design (i.e. design of the process and mechanical equipment’s) safety and environment, technical challenges associated with the process plant of gas to liquid (GTL). The Syngas production unit, Fischer Tropsch synthesis, refining of the GTL liquids to transport fuels (Product up-grade) have been modelled (simulated) using Aspen HYSYS software. The results of this simulation and the actual results obtained in experiment (Choi et al, Bechtel. 1996) were compared and are practically in reasonable agreement with each other. The book is especially useful to engineering students, Petroleum and gas engineers, Process and chemical engineers, and Mechanical engineers in the oil and gas sector.
Ruthenium compounds have shown very good second order and third order behaviour. Very high non-linear optical (NLO) response is due to the extensive coordination and organometallic chemistry of ruthenium. Electron-rich d6 ruthenium (II) centres are especially well-suited for incorporation into NLO chromophores because their highly polarizable d orbitals can cause effective ?-electron-donating properties when coordinated to ligands with low-lying ?* orbitals. This work provides an understanding of the NLO properties of ruthenium complexes. All systems display large second-order NLO response. This effort may provide the guidelines to synthesize the high-performance NLO materials. The present investigation gives insight into the NLO response of ruthenium complexes and endeavors to disclose the origin of the NLO response of this family, which is interesting and important in design and synthesis of new promising NLO materials.
Gas-inducing stirred tank reactors (GISTs) are very attractive for industrial chemical processes where efficient mixing holds the key to superior product yield and quality particularly in situations where the reaction has a low conversion per pass as is the case for the Fischer-Tropsch (FT) synthesis. However, the benefits can only be properly harnessed if there is a reliable set of quantitative relations between operating variables and the mixing attributes as well as reaction metrics. Thus, this book provides a pioneering investigation of electrical process tomography-aided GIST operation based on the FT reaction in order to correlate reaction metrics with mixing characteristics. The technique is non-invasive, using electrical signals corresponding to changes in the component distribution within the vessel with the aid of reconstruction algorithms. In addition, CFD also was used to elucidate the hydrodynamic behaviour within the system. In the FT reaction, the steady-state gas phase hold-up dependency on temperature was shown to be due to contributions from both thermal expansion and reaction-induced changes in the liquid phase.
Anglo Platinum currently stores some of its recovered osmium as the relatively stable potassium osmate salt and ruthenium in the form of ammonium hexachlororuthenate or an acidic ruthenium solution at its refinery plant. To date the development of the chemistry of these starting materials to provide useful inorganic and organometallic precursors has not been extensively reported. This is partly due to the relative cost of osmium starting materials and the inertness of most osmium complexes and also the toxicity of osmium tetroxide. Most known ruthenium compounds are usually made from ruthenium trichloride trihydrate.In the present project locally available refinery materials have been converted into a range of known osmium and ruthenium compounds including clusters together with the well known Grubbs'' catalyst starting material as well as other useful complexes. The development of the synthesis of convenient osmium and ruthenium precursors as well as potential catalysts has been proven to be possible based on standard (literature) synthetic methods using the Anglo Platinum refinery material. Some procedures are new and some are modified literature procedures.
"Breakthrough in conversion of abundant natural resources such as natural gas, biomass, and coal to ultra-clean fuels and value added chemicals requires design of non-conventional and energy integrated technologies. This book provides fundamentals and applications for the utilization of non-conventional reaction media such as the supercritical fluids in the Fischer Tropsch reactor, which is the heart of gas-to-liquid technology. This medium provides unique properties between the gas and the liquid reaction media and yields a highly efficient reactor system that can provide several advantages over the current commercial technologies.”
It could be noted from the literature that the presence of the Ru(II) complexes is found to have anticancer activities. Ruthenium metal is known for a long time. But its discovery as a therapeutic agent has recently. Researchers are focused on the synthesis of ruthenium complexes. Ruthenium has to be incorporated in a complex to make it soluble in body fluids.In the search for anticancer active metal complexes several ruthenium complexes have been reported to be promising as anticancer drugs.Ruthenium also has three main properties that make ruthenium complexes well suited metal for medicinal application. i) Ligand exchange rate, ii) The ability of ruthenium to mimic iron in binding to certain biological molecules. iii) The range of accessible oxidation states. Since tris chelates of ruthenium complexes show intercalative properties with the DNA molecule in-vitro, our main objective was to synthesize several mononuclear ruthenium(II) complexes and evaluate them for in-vitro cytotoxic activity.
Scientific community has shown decent research interest in the field of organometallic complexes based on platinum group metals owing to their plausible use in synthetic and industrial chemistry. In this regard, transition metal complexes containing ?6-arene, ?5-Cp and Cp* have drawn special attention. In particular, arene complexes have emerged as versatile intermediate in organic synthesis as a consequence of the ease with which the arene ligand can be functionalized. The presence of a transition metal center and ancillary ligands on one face of the coordinated arene can serve as a valuable stereochemical element. The utility of ?6-arene and ?5-Cp and Cp* metal complexes emanates not only from the reactivity inherent to the coordinated ring but, also from the control over three facially disposed coordinated sites about a given metal center afforded by incorporation of an arene ligand. In search of new systems based on arene ruthenium chemistry which can behave as potential metallo-ligands, new ?6-arene ruthenium and analogous ?5-Cp complexes based on chelating N,N and N,O donor ligands and non-chelating nitrogen donor organic ligands has been synthesized and fully characterized.
Whilst the chemotherapeutic success of platinum is undeniable, it is by no means the perfect drug. It is not effective against many common types of cancer, drug resistance is common and it has a deplorable range of side effects, which can include nerve damage, hair loss and nausea. To overcome these limitations, some compounds based on ruthenium have been developed and tested against cancer cell lines. These compounds tend to cause fewer side effects compared to platinum drugs. Ruthenium compounds represent one of the great success stories of metals in medicine. Two ruthenium compounds are currently undergoing clinical evaluation as anticancer drugs NAMI-A and KP1019. A great deal of the remaining ruthenium complexes, these efforts are continue today with increased realization that new strategies are needed to overcome issues of toxicity and resistances inherent treatment by the ruthenium anticancer agents. The present study deals with the new strategies for the development of novel ruthenium compounds and screened for the in vivo anticancer activity against transplantable murine tumor cell lines.
Series of cobalt catalysts supported on carbon nanofibers have been investigated to study the effect of Co particle size in the Fischer-Tropsch synthesis. The performance of the Cobalt catalysts on the FT reaction was proven that the activity decreased for cobalt particles smaller than 6 nm. The activation energy measurements for these small cobalt particles revealed that the activation energy increased. The carbon coverage of Co particles after FT synthesis was studied with Temperature Programmed Hydrogenation and Temperature-programmed Surface Reaction. The low activity on small cobalt particles was caused by carbon deposition on the surface of the cobalt metal. Investigation on intrinsic activity or intrinsic turn over frequency, based on specific cobalt particle size, gave an indication of optimum particle size for mono-disperse system. Mathematical models from Van Hardeveld and Hartog applied on cobalt catalyst showed that there is a correlation between the fraction of active and inactive particles with the fraction of face and edge atoms on the particle surface, respectively
Hydrogen can be produced by numerous techniques, with no emission of pollutants and green house gases. Hydrogen has a number of attractive advantages such as high energy density, non-toxic reaction products and abundant natural resources. Sodium borohydride has been considered as hydrogen storage material in the use of renewable energy sources on the way towards sustainable energy of the future. Via this research work, we studied the effect of different phosphorus compounds on the catalytic activity of ruthenium(III) acetylacetonate in the hydrolysis of sodium borohydride and on the kinetics of the catalytic hydrolysis. In addition, synthesis and characterization of ruthenium(III) acetylacetonato complexes containing two trimethylphosphite ligands were studied. Finally, isolation, stabilization and characterization of new ruthenium species (active catalyst), formed during catalytic hydrolysis of sodium borohydride starting with Ru(acac)3 and P(OMe)3, were discussed.
Ruthenium complexes are also important as antitumor agents and some are currently under clinical trials. It follows a novel mechanism of action with the prospect of non-cross-resistance, reduced toxicity and acquires different activity. The Ruthenium complexes are suitable towards cisplatin resistance cancer cells, and efficiently exert antitumor action, which may be in part due to the ability of ruthenium complexes to mimic the binding of iron to certain biological molecules that in fact exploits a mechanism for non-toxic transport of iron inside the body. This property is especially attractive for ruthenium complexes. The ability of ruthenium to mimic iron in binding to certain biological molecules make these complexes well suitable for medicinal use, and as an alternative for the platinum anticancer drugs in the treatment of cancer cells, resistant to cisplatin and its analogues. The water soluble Ru complexes are usually suitable for medicinal use, and several Ru based drugs have shown good anticancer activity.The Ru complexes have certain advantages than the platinum complexes due to its solubility in water and low toxicity.