The Experts below are selected from a list of 315 Experts worldwide ranked by ideXlab platform
Arno De Klerk - One of the best experts on this subject based on the ideXlab platform.
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Integration of Fischer–Tropsch and Oilsands Bitumen Production Processes
Energy & Fuels, 2016Co-Authors: Arno De KlerkAbstract:Oilsands bitumen production facilities need heat, water, and hydrogen to recover and upgrade bitumen. Hydrogen is usually derived from synthesis gas, which also provides an opportunity for Fischer–Tropsch synthesis. Heat, process, and product integration benefits were pointed out in the literature, and the literature was reviewed. New integration opportunities were identified, as well as technical aspects that should be considered in such integration. Heat integration of air separation and the impact of Fischer–Tropsch technology selection on the quality of heat integration were discussed. Integration of water management and the potential use of the Fischer–Tropsch aqueous products for bitumen recovery, demetalation, viscosity reduction, and pH management were described. Limited opportunity for integration of gas cleaning was found. Process integration during primary product separation, as well as various strategies to derive more benefit from gaseous products, was outlined. Gaseous product processing str...
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Improving the Interface between Fischer–Tropsch Synthesis and Refining
Energy & Fuels, 2013Co-Authors: Daniel F. Rodríguez Vallejo, Arno De KlerkAbstract:In a typical industrial Fischer–Tropsch process the hot reaction product from Fischer–Tropsch synthesis is stepwise cooled, condensed, and recovered, before being separated by distillation into different cuts. A different design was proposed whereby the hot reaction products are directly introduced into a pressure distillation unit, which combines syncrude recovery and distillation. Process simulation was employed to evaluate the proposal. It was found that integration of syncrude recovery and distillation was technically viable and that it had a number of benefits compared to stepwise cooling and recovery of syncrude prior to distillation. These positive outcomes were independent of the type of Fischer–Tropsch technology used. Some notable benefits included a decrease in heating/cooling duty, improved liquid recovery, and reduced loading of tail gas separation. The proposed design also enabled other improvements, such as a strategy to improve catalyst-wax separation from slurry bubble column reactors and...
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Kirk‐Othmer Encyclopedia of Chemical Technology - Fischer–Tropsch Process
Kirk-Othmer Encyclopedia of Chemical Technology, 2013Co-Authors: Arno De KlerkAbstract:A Fischer–Tropsch process always forms part of a larger indirect liquefaction facility, which consists of three processing steps. The first step is to convert a carbon source, such as coal, natural gas, biomass, or organic waste, into synthesis gas (syngas). Syngas is a mixture of hydrogen and carbon monoxide, and it is the feed material for a Fischer–Tropsch process, which is the second step in the indirect liquefaction process. Fischer–Tropsch synthesis is the catalytic polymerization and hydrogenation of CO, which produces a synthetic crude oil (syncrude). The syncrude is a multiphase mixture of hydrocarbons, oxygenates, and water. The third step is the refining of the syncrude to products that are traditionally produced from conventional crude oil, such as transportation fuels and petrochemicals. The current contribution deals only with the Fischer–Tropsch process; the generation of syngas and the refining of Fischer–Tropsch syncrude are not discussed in any detail. A Fischer–Tropsch process has three main elements: catalyst, reactor, and gas loop. Fischer–Tropsch catalysis is described to explain the relationship among the different catalyst types, operating conditions, and products. A description of the main syncrude types and their compositions is also provided. Fischer–Tropsch technologies are discussed, with an explanation of the relationship between catalyst and reactor, the tradeoffs involved in different catalyst–reactor combinations, as well as guidelines for technology selection. The role of the Fischer–Tropsch gas loop is outlined, with a discussion of the key elements of the gas loop and how they affect the overall performance of a Fischer–Tropsch process. Keywords: Fischer–Tropsch; synthesis gas (syngas); synthetic crude oil (syncrude); indirect liquefaction; coal-to-liquids; gas-to-liquids; biomass-to-liquids
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Fischer-Tropsch Refining
2011Co-Authors: Arno De KlerkAbstract:Introduction. Fischer-Tropsch facilities at a glance -- Refining and refineries at a glance -- Production of Fischer-Tropsch syncrude. Synthesis gas production, cleaning, and conditioning -- Fischer-Tropsch synthesis -- Fischer-Tropsch gas loop -- Industrial Fischer-Tropsch facilities. German Fischer-Tropsch facilities -- American hydrocol facility -- Sasol 1 facility -- Sasol 2 and 3 facilities -- Mossgas facility -- Shell middle distillate synthesis (SMDS) facilities -- Oryx and Escravos gas-to-liquids facilities -- Synthetic transportation fuels. Motor-gasoline -- Jet fuel -- Diesel fuel -- Refining technology. Refining technology selection -- Dehydration, etherification, and hydration -- Isomerization -- Oligomerization -- Aromatic alkylation -- Cracking -- Reforming and aromatization -- Chemical technologies -- Refinery design. Principles of refinery design -- Motor-gasoline refining -- Jet fuel refining -- Diesel fuel refining -- Chemicals and lubricant refining.
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Can Fischer−Tropsch Syncrude Be Refined to On-Specification Diesel Fuel?
Energy & Fuels, 2009Co-Authors: Arno De KlerkAbstract:The interchangeable colloquial use of the terms “distillate” (boiling range) and “diesel fuel” (distillate meeting legislated fuel specifications), led to misleading perceptions about the suitability of Fischer−Tropsch syncrude for diesel fuel production. Two questions are addressed: Can Fischer−Tropsch syncrude be refined to diesel fuel, and which Fischer−Tropsch technology is best for maximizing distillate and ultimately diesel fuel production? The distillate yield that can be obtained from Fischer−Tropsch syncrude in an uncomplicated refinery employing only hydrocracking and/or oligomerization follows the order: Fe-LTFT > Co-LTFT > Fe-HTFT. Conversely, producing diesel fuel (not distillate) from Fe-HTFT syncrude is easier. On a molecular level, Fischer−Tropsch syncrude was found to be unsuitable for the production of EN 590:2004 diesel fuel in high yield. There is a trade-off between distillate density, cetane number, and yield, which is called the Fischer−Tropsch density−cetane−yield triangle. It is p...
P J Van Berge - One of the best experts on this subject based on the ideXlab platform.
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Advances in the cobalt catalyzed Fischer-Tropsch synthesis
2020Co-Authors: P J Van Berge, Sean Barradas, J. V. A. N. De Loodsrecht, Jacobus Lucas VisagieAbstract:A industrial application of the Fischer-Tropsch synthesis was dominated by cobalt-based catalysis over the period. 1925-1950, surpassed by iron-based catalysis that dominated the period; 1936-2000. The industrial application of the cobalt-based Fischer-Tropsch synthesis re-emerged roundabout 1975, and holds the potential of reclaiming dominance aided by the significant attention that the Gas-to-Liquids (GTL) process is receiving, an option to monetise crude oil associated gas as an alternative to either flaring or re-injection. The Fischer-Tropsch technology of choice. as an integral part of a GTL plant, is the combination of the proved slurry phase bubble column reactor with a highly active and stable supported cobalt catalyst, the potential single train capacity being reported as 20,000 bbl/day. The Fischer-Tropsch synthesis performance criteria for a tailor-made cobalt-based slurry phase catalyst were quantified from SASOL's perspective, and the conclusion was reached that the current status of this technology justifies its commercialization. The simplest concept would be the production of gas-oil (80%) and naphtha (20%), requiring an economy of scale GTL plant ( 30,000 bbl/d), feasible at a crude oil price e in excess of US $ 16/bbl.
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oxidation of cobalt based fischer tropsch catalysts as a deactivation mechanism
Catalysis Today, 2000Co-Authors: P J Van Berge, J Van De Loosdrecht, Sean Barradas, A M Van Der KraanAbstract:The oxidation of supported cobalt based slurry bed Fischer–Tropsch catalysts by means of water was studied. Water is one of the Fischer–Tropsch reaction products and can probably cause oxidation and deactivation of a reduced cobalt catalyst. Model experiments using Mossbauer emission spectroscopy and thermogravimetry as well as realistic Fischer–Tropsch synthesis runs were performed. It was demonstrated that Mossbauer emission spectroscopy can successfully be applied to the investigation of high cobalt loading Fischer–Tropsch catalysts. Strong indications were found that oxidation of reduced cobalt catalysts occurs under realistic Fischer–Tropsch conditions. Mossbauer emission spectroscopy and thermogravimetry results showed that the oxidation depends on the PH2/PH2O ratio, and that oxidation proceeds to less than complete extents under certain conditions. The formation of both reducible and less reducible cobalt oxide species was observed, and the relative ratio between these species depends on the severity of the oxidation conditions.
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Oxidation of cobalt based Fischer–Tropsch catalysts as a deactivation mechanism
Catalysis Today, 2000Co-Authors: P J Van Berge, J Van De Loosdrecht, Sean Barradas, A M Van Der KraanAbstract:The oxidation of supported cobalt based slurry bed Fischer–Tropsch catalysts by means of water was studied. Water is one of the Fischer–Tropsch reaction products and can probably cause oxidation and deactivation of a reduced cobalt catalyst. Model experiments using Mossbauer emission spectroscopy and thermogravimetry as well as realistic Fischer–Tropsch synthesis runs were performed. It was demonstrated that Mossbauer emission spectroscopy can successfully be applied to the investigation of high cobalt loading Fischer–Tropsch catalysts. Strong indications were found that oxidation of reduced cobalt catalysts occurs under realistic Fischer–Tropsch conditions. Mossbauer emission spectroscopy and thermogravimetry results showed that the oxidation depends on the PH2/PH2O ratio, and that oxidation proceeds to less than complete extents under certain conditions. The formation of both reducible and less reducible cobalt oxide species was observed, and the relative ratio between these species depends on the severity of the oxidation conditions.
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The oxidation of cobalt based Fischer-Tropsch catalysts as studied by Mössbauer emission spectroscopy
Preprints-American Chemical Society Division of Petroleum Chemistry, 1999Co-Authors: P J Van Berge, J Van De Loosdrecht, Sean Barradas, A M Van Der KraanAbstract:This paper concentrates on the oxidation of a state of the art cobalt based Fischer-Tropsch catalyst as studied via Mossbauer emission spectroscopy as well as Fischer-Tropsch synthesis.
Anders Holmen - One of the best experts on this subject based on the ideXlab platform.
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Deactivation of cobalt based Fischer―Tropsch catalysts: A review
Catalysis Today, 2010Co-Authors: Nikolaos E Tsakoumis, Øyvind Borg, Magnus Ronning, Erling Rytter, Anders HolmenAbstract:Abstract To trace the origin of catalyst deactivation is in many cases difficult. It is usually a complex problem where several mechanisms contribute to the loss of activity/selectivity. Low temperature Fischer–Tropsch synthesis (FTS) is a three phase system having a wide range of products and intermediates. Additionally, high partial pressures of steam will arise during reaction. Thus, the chemical environment in the Fischer–Tropsch synthesis reactor encompasses a large number of interacting species which may negatively affect catalytic activity. Furthermore, it is an exothermic reaction and local overheating might occur. Utilization of the produced heat is crucial and the choice of the reactor should be done with respect to the catalyst stability properties. Catalyst deactivation in the Fischer–Tropsch reaction has been a topic of industrial as well as academic interest for many years. The main causes of catalyst deactivation in cobalt based FTS as they appear in the literature are poisoning, re-oxidation of cobalt active sites, formation of surface carbon species, carbidization, surface reconstruction, sintering of cobalt crystallites, metal–support solid state reactions and attrition. The present study focuses on cobalt catalyzed Fischer–Tropsch synthesis. The various deactivation routes are reviewed, categorized and presented with respect to the most recent literature.
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deactivation of cobalt based fischer tropsch catalysts a review
Catalysis Today, 2010Co-Authors: Nikolaos E Tsakoumis, Øyvind Borg, Magnus Ronning, Erling Rytter, Anders HolmenAbstract:Abstract To trace the origin of catalyst deactivation is in many cases difficult. It is usually a complex problem where several mechanisms contribute to the loss of activity/selectivity. Low temperature Fischer–Tropsch synthesis (FTS) is a three phase system having a wide range of products and intermediates. Additionally, high partial pressures of steam will arise during reaction. Thus, the chemical environment in the Fischer–Tropsch synthesis reactor encompasses a large number of interacting species which may negatively affect catalytic activity. Furthermore, it is an exothermic reaction and local overheating might occur. Utilization of the produced heat is crucial and the choice of the reactor should be done with respect to the catalyst stability properties. Catalyst deactivation in the Fischer–Tropsch reaction has been a topic of industrial as well as academic interest for many years. The main causes of catalyst deactivation in cobalt based FTS as they appear in the literature are poisoning, re-oxidation of cobalt active sites, formation of surface carbon species, carbidization, surface reconstruction, sintering of cobalt crystallites, metal–support solid state reactions and attrition. The present study focuses on cobalt catalyzed Fischer–Tropsch synthesis. The various deactivation routes are reviewed, categorized and presented with respect to the most recent literature.
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Fischer-Tropsch synthesis on cobalt catalysts: the effect of water
Catalysis, 2007Co-Authors: Edd A. Blekkan, Øyvind Borg, Vidar Frøseth, Anders HolmenAbstract:Modern GTL (Gas-to-Liquids) technology involves Fischer-Tropsch synthesis for converting natural gas derived synthesis gas to transportation fuels.1 The Fischer-Tropsch synthesis (FTS) produces a complex mixture of hydrocarbons, consisting of methane, C2+ olefins and paraffins (linear and branched) ...
A M Van Der Kraan - One of the best experts on this subject based on the ideXlab platform.
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oxidation of cobalt based fischer tropsch catalysts as a deactivation mechanism
Catalysis Today, 2000Co-Authors: P J Van Berge, J Van De Loosdrecht, Sean Barradas, A M Van Der KraanAbstract:The oxidation of supported cobalt based slurry bed Fischer–Tropsch catalysts by means of water was studied. Water is one of the Fischer–Tropsch reaction products and can probably cause oxidation and deactivation of a reduced cobalt catalyst. Model experiments using Mossbauer emission spectroscopy and thermogravimetry as well as realistic Fischer–Tropsch synthesis runs were performed. It was demonstrated that Mossbauer emission spectroscopy can successfully be applied to the investigation of high cobalt loading Fischer–Tropsch catalysts. Strong indications were found that oxidation of reduced cobalt catalysts occurs under realistic Fischer–Tropsch conditions. Mossbauer emission spectroscopy and thermogravimetry results showed that the oxidation depends on the PH2/PH2O ratio, and that oxidation proceeds to less than complete extents under certain conditions. The formation of both reducible and less reducible cobalt oxide species was observed, and the relative ratio between these species depends on the severity of the oxidation conditions.
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Oxidation of cobalt based Fischer–Tropsch catalysts as a deactivation mechanism
Catalysis Today, 2000Co-Authors: P J Van Berge, J Van De Loosdrecht, Sean Barradas, A M Van Der KraanAbstract:The oxidation of supported cobalt based slurry bed Fischer–Tropsch catalysts by means of water was studied. Water is one of the Fischer–Tropsch reaction products and can probably cause oxidation and deactivation of a reduced cobalt catalyst. Model experiments using Mossbauer emission spectroscopy and thermogravimetry as well as realistic Fischer–Tropsch synthesis runs were performed. It was demonstrated that Mossbauer emission spectroscopy can successfully be applied to the investigation of high cobalt loading Fischer–Tropsch catalysts. Strong indications were found that oxidation of reduced cobalt catalysts occurs under realistic Fischer–Tropsch conditions. Mossbauer emission spectroscopy and thermogravimetry results showed that the oxidation depends on the PH2/PH2O ratio, and that oxidation proceeds to less than complete extents under certain conditions. The formation of both reducible and less reducible cobalt oxide species was observed, and the relative ratio between these species depends on the severity of the oxidation conditions.
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The oxidation of cobalt based Fischer-Tropsch catalysts as studied by Mössbauer emission spectroscopy
Preprints-American Chemical Society Division of Petroleum Chemistry, 1999Co-Authors: P J Van Berge, J Van De Loosdrecht, Sean Barradas, A M Van Der KraanAbstract:This paper concentrates on the oxidation of a state of the art cobalt based Fischer-Tropsch catalyst as studied via Mossbauer emission spectroscopy as well as Fischer-Tropsch synthesis.
Bert M Weckhuysen - One of the best experts on this subject based on the ideXlab platform.
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the renaissance of iron based fischer tropsch synthesis on the multifaceted catalyst deactivation behaviour
Chemical Society Reviews, 2008Co-Authors: Emiel De Smit, Bert M WeckhuysenAbstract:Iron-based Fischer–Tropsch catalysts, which are applied in the conversion of CO and H2 into longer hydrocarbon chains, are historically amongst the most intensively studied systems in heterogeneous catalysis. Despite this, fundamental understanding of the complex and dynamic chemistry of the iron–carbon–oxygen system and its implications for the rapid deactivation of the iron-based catalysts is still a developing field. Fischer–Tropsch catalysis is characterized by its multidisciplinary nature and therefore deals with a wide variety of fundamental chemical and physical problems. This critical review will summarize the current state of knowledge of the underlying mechanisms for the activation and eventual deactivation of iron-based Fischer–Tropsch catalysts and suggest systematic approaches for relating chemical identity to performance in next generation iron-based catalyst systems (210 references).