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NNadir's Journal - Archives
 Paul Sattler, Contemporary, American 1999.
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The six-unit Gravelines nuclear power plant near Dunkerque in northern France has become the first nuclear plant in the world to deliver 1000 billion kilowatt-hours (one petawatt-hour) of electricity. Electricité de France (EdF) recently announced that on the 27 August 2010 the Gravelines nuclear power plant had delivered its 1000 billionth kWh (one PWh) of electricity. It is the first nuclear power site to generate this historic figure, which is equal to twice the annual consumption of the whole of France... ...The Graveline plant is neither the biggest nuclear power plant in the world, nor the oldest. It attributes its success in reaching the milestone figure to a combination of skilled staff, successful operation and maintenance management, and standardised design. Significantly, no major safety incident has ever taken place at the Gravelines plant, which has also helped lower worker dose by a factor of two in the past decade. All six units of the Gravelines plant were commissioned between 1980 and 1984. Over its 30 years of operation it has contributed to the economy enormously, including €4 billion ($6 billion) in workers' wages and €3.6 billion ($5 billion) in taxes. It has also spent about €4 billion ($6 billion) in maintenance and provided an average yearly amount of €120 million ($168 million) for contracts, mainly to local subcontractors... ...To place one PWh in context with other sources, it is roughly equal to the amount of electricity obtained from burning either 350 million tonnes of coal, 220 million tonnes of oil or 60 billion cubic metres of gas. Alternatively, it is the same as what could potentially be generated by 200,000 two-megawatt wind turbines operating over the same 30-year period. The nuclear reactors at Gravelines have saved 1000 million tonnes of carbon dioxide that would have been emitted to the atmosphere had coal been burnt instead. The high-level waste from the plant – which has been subjected to reprocessing – fills a volume about one-third that of an Olympic-sized swimming pool. French reactor reaches generation landmark Note that a Petawatt-hour is a unit of energy, not power. The reactors that produced this feat are all pictured in a single photograph that can be seen by following the link. Have a nice evening.
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Argentina has formally reactivated its gaseous diffusion uranium enrichment plant at Pilcaniyeu over two decades after production there halted. The plant is expected to become operational in September 2011... ...Argentina currently has two operating nuclear reactors, at Embalse and Atucha. The reactivation of Pilcaniyeu is part of an Argentinian nuclear energy policy that has also seen the resumption of work on the partially built Atucha II pressurised heavy water reactor, due to go online in 2011, with plans for a third reactor at the site to follow. To that end, Argentina has been pursuing contacts with likely reactor suppliers over recent months, signing a memorandum of understanding with South Korea in September and a cooperation agreement with Russia in April 2010. Talks have also been held with China about the possibility of building a second unit at Embalse. Argentina celebrates enrichment plant reactivation They actually do not need enriched fuel, since they could operate the PHWR with used nuclear fuel from many other countries, including the United States, but maybe they are looking to sell fuel to China.
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 Max Beckman (1884-1950) Oil on Canvas, 1938 German At the Neue Gallerie, New York.
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 Ferdinand Hodler, Swiss, 1853-1918. At Kunsthaus Zurich.
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Hindustan Construction Company (HCC) will undertake main plant civil works of units 7 and 8 of the Rajasthan Atomic Power Project (RAPP) after a Rs8880 million ($188 million) contract by Nuclear Power Corporation of India Ltd (NPCIL). RAPP 7 and 8 will be 700 MWe indigenously designed pressurized heavy water reactors (PHWRs). The units are scheduled to begin commercial operation in June and December 2016, respectively. HCC has constructed all six existing units at RAPP, which are also PHWRs of varying sizes, the first of which began operating in 1973 and the latest earlier this year. Under the latest contract, the scope of the work involves construction of the reactor buildings, auxiliary buildings and the waste management exhaust ventilation building... The bold is mine, as is placed there to show what a nation with a nuclear infrastructure can do. Contract for Indian reactor components. I personally regard the Indian Nuclear Power program to be one of the most innovative and exciting in the world, because of India's huge thorium resources, which India clearly intends to exploit. While the rest of the world is trying to wipe up its oil with Downey paper towels, India will come to possess the world's largest supply of U-233, which will place them in the cat bird seat for a huge portion of the 21st century. The United States possesses about one ton of U-233, manufactured from thorium in the last half of the 20th century, some of it in our very first commercial nuclear reactor, Shippingport, which operated for about 3 years as a thermal breeder reactor during the Carter administration. We're so wise here, that we're thinking of throwing it away.
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Titanium is not a rare element on earth. The oxide, TiO2 is widely used in paints and a host of other applications, including in sunscreens and in photocatalytic materials. The price of purified TiO2 is in the neighborhood of $150/ton.
Titanium metal on the other hand, which is used mostly in aerospace applications, including famously the SR-71 Blackbird spy plane, is very expensive and often difficult to obtain. This has been a shame, since the metal is superior to steel inasmuch as it is refractory (wrt steel) and light weight (wrt steel). If the frame of the World Trade Center had been titanium rather than steel, the building may have withstood the attack by dangerous fossil fuel terrorists with comparatively minor damage. The reason that the metal is expensive while the ore is cheap is the same reason that Napoleon III had aluminum dinner service at his palace as a display of his wealth. In former times, the reduction of alumina (the ore) to aluminum was very difficult and therefore very expenive. After the electrolytic molten salt Hall process was discovered, aluminum became cheap and Napoleon's expensive dinnerware became rather ordinary. I have been aware of a new titanium reduction process that is electrolytic, and was patented about 8 or 10 years ago. This should improve access to titanium metal in the long run. A recent paper in the scientific literature that I had cause to contemplate touches on this subject. The paper is "Molten salt applications in materials processing" and the reference is Journal of Physics and Chemistry of Solids 66 (2005) 396–401 Mostly the paper refers to the refining of calcium metal, using a novel porous ceramic sheath around the annode. Some excerpts of the paper beginning with the introduction: Molten salt processing provides a unique opportunity to process and produce metals where gas-based pyro-reduction, metallothermic reduction, hydrometallurgical methods or aqueous electrochemical techniques are not feasible due to thermodynamic or kinetic constraints. Industrial applications of molten salts have been well recognized for more than century. In spite of the use of high temperature corrosive liquids, molten salts offer unique opportunities. The steel and other non-ferrous metal industries make use of molten salts and slags for refining and precision heat treatment. Commercial production of aluminum, magnesium, sodium, potassium, lithium, beryllium, etc. make use of molten salt reduction or electrolysis, since any other method is technoeconomically not feasible. Several other reactive metals, such as lanthanides and actinides make use of molten salt processing for extraction and refining. Additionally, the high temperature carbothermic or metallothermic smelting reduction methods for metal production are associated with the generation of significant quantity of waste as slags. There’s a need to develop alternative processes that have low waster ideally a ‘zero-waste’ generation. Low temperature multicomponent molten salts <1>, as well as room temperature ionic liquids <2> have been developed for materials processing. Molten salts are also finding applications in fuel cell technology. The process described in this paper for producing metals is primarily aimed at complete recycling of process waste. It is also anticipated that the suggested scheme will lower the production cost, since the reductant is electrolytically generated. Significant research effort has been invested in recent times for producing titanium and other refractory metals by molten salt processing. Implementation of this scheme with respect to titanium production is demonstrated <3–5>... Further on: ...A number of research studies have been initiated to prepare a waste-minimization strategy <6–9>. This work describes two aspects of the overall metal production program: (a) electrolytic recovery of calcium metal from theDOR process effluent salt comprising calcium oxide and calcium chloride and (b) use of electrolytically recovered calcium metal in situ as a reductant in a hybrid reactor. There are several advantages of the suggested hybrid process. The process ideally produces ‘zero’ waste and themetals can be recovered from inexpensive oxides/chlorides without the need for an expensive reductant. Oxygencarbon dioxide and chlorine gases are the only process effluent which can be easily contained. Operational costs include graphite anode, electric power and recyclable salt only. The process is also amenable to alloy production directly by incorporating co-reduction of respective oxides... The paper ends thusly. ...The process could be conducted under a cover ofnitrogen gas in the electrowinning and reduction chamber, since the metals are not exposed to high temperature atmosphere and are always contained within the salt phase.Fig. 4 shows two such possible designs that have been adopted to produce titanium metal (OS Process) byelectrolytically winning calcium and using it simultaneously to reduce titanium oxide <11>. In Fig. 4a, the calcium chloride salt with electrodeposited calcium is transferred into another reactor where the reduction of titania takes place. In the design shown in Fig. 4b, titania is introduced in the same chamber and the reduction idaffected by the calcium deposited on the iron cathode. 6. Conclusion Calcium can be electrolytically produced by dissociating calcium oxide in a molten calcium chloride electrolyte. Aporous ceramic diaphragm around the anode is essential for separating the anolyte and catholyte to be able tocathodically deposit calcium. The cell temperature, fluidity of salt and porosity of the sheath are critical in recovering calcium. Ionic diffusion through the sheath is the rate controlling step. A diffusion coefficient in the range of 10K5to 10K6 cm2/s is obtained for a 30% porous alumina sheath for cell temperatures between 800 and 9008C.A hybrid process is investigated consisting of electrowinning calcium from calcium oxide and in situ utilization of calcium as a reductant within the same reactor. Silver, tin, lead and bismuth can be produced by pyrochemical reduction of their respective chlorides and/or oxides with calcium in a calcium chloride medium. These metals were produced as a surrogate for a certain radioactive metal. Cool. I cite this paper as a demonstration of two of the three R's they teach kids Recyle and Reduce. We can make better materials cheaper and more sustainably if we invest in intellectual capital.
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Recent Advances In the Catalysis of HI Decomposition to Give Hydrogen in the SI Cycle.
The SI cycle or “sulfur iodine” cycle, about which I have written here and elsewhere before, consists of the following chemical reactions: I2 + SO2 + 2H2O ↔ 2HI + H2 SO4 (a) 2HI ↔ H2 + I2 H2 SO4 ↔ SO2 + H2O + 0.5O2 It is a thermochemical means of splitting water at lower temperatures, temperatures that are accessible industrially, than would be required for the direct decomposition of water into its elements. These reactions are catalytic and can be utilized to make the direct conversion of industrial grade heat into hydrogen and oxygen, offering the potential for phasing out the dangerous fossil fuel petroleum by providing captive hydrogen to manufacture clean fuels like DME (dimethyl ether). This approach would take place via the direct hydrogenation of carbon oxides including carbon dioxide the dangerous fossil fuel waste that the dangerous fossil fuel industry dumps indiscriminately in Earth’s atmosphere. (The hydrogenation of carbon oxides to give DME is already an industrial process, but regrettably the sources of hydrogen for these applications are the dangerous fossil fuels coal and natural gas.) Many hundreds of these cycles have been proposed or studied; some are better than others. Without question, the most advanced such cycle, generating a huge number of publications in the last few years, is the SI cycle given above. It is not necessarily the best possible cycle, but it is clearly the one that will go industrial first, probably in China. The status of the Chinese program can be found in a recent publication in the scientific literature, International Journal of Hydrogen Energy Volume 35, Issue 7, April 2010, Pages 2883-2887, in a paper entititled, “Overview of nuclear hydrogen production research through iodine sulfur process at INET.” China has recently constructed at test nuclear reactor of the “pebble bed” type originally developed in Germany and is using it to explore possible applications for process heat to run chemical reactions including, but not limited to, the SI cycle. According to the paper just cited, China has advanced from the laboratory scale to the bench top scale with the SI cycle and will conduct pilot plant operations about 3 years from now. The HTR-10 test nuclear driven thermochemical hydrogen production pilot is now scheduled for 2019, about a year earlier than was being talked about a few years back, indicating that the Chinese program is quite serious. This makes the timeline competitive with that being undertaken by KAERI, the Korean Atomic Energy Research Institute, and way more advanced, as I understand it, than the work being done at CEA, the French Nuclear Research Institute and the work being conducted at Sandia, since we don’t have high temperature reactors. (France is working to build one in Central Europe, probably in the Czech Republic, Slovakia or Hungary, as part of its work in an international consortium.) One of the chemical problems of the reaction series is obtaining appropriate kinetics for the critical step of the decomposition of hydrogen iodide, “hydroiodic acid,” to give free hydrogen. Significant work on catalysis of this reaction is an active area of research. Of considerable interest are ceria based catalysts which include platinum containing systems. The Chinese have just published a work on the use of a nickel based analogue, which of course would be much cheaper and I think it’s pretty exciting and decided to reference the paper here, even though I’m not necessarily an SI kind of guy, although I’d rather see the SI process used than no thermochemical hydrogen process, since it is a critical task for humanity to present the next generation with a means of phasing out – as quickly as is possible – dangerous oil, no matter what line of horseshit is handed out by dangerous fossil fuel marketers and greenwashers like the ignorant anti-nuke Amory Lovins. (I would argue that commercialization of these kinds of process should be subject to huge international efforts, fully funded to the maximal extent to dramatically shorten the currently observed timelines. We should have hundreds of thousands of chemists and engineers working full time on this, day and night.) Whatever. Here is the paper on the new Ni based CeO2: International Journal of Hydrogen Energy Volume 34, Issue 21, November 2009, Pages 8792-8798 Some excerpts from the text of this paper follow: Among the large-scale, cost effective and environmentally attractive thermochemical cycles, the sulfur–iodine (SI or IS) thermochemical cycle is a quite promising one. The potential of the SI process for hydrogen production has been indicated by many researchers <1–14>… The Bunsen reaction (a) is an exothermic SO2 gas-absorbing reaction in an aqueous phase. The hydrogen iodide (HI) solution and the H2SO4 solution are separated by a liquid–liquid phase separation phenomenon that occurs in the presence of an excess I2. The two acids were divided into upper and lower solutions with a clear boundary. The separated HI solution and H2SO4 solution are purified, concentrated, vaporized and decomposed to produce H2 (b) and O2 (c). All chemicals in the cycle are recycled and H2O is decomposed into H2 and O2 in total. Among these reactions, HI decomposition presents a rather low homogeneous gas-phase conversion even at high operating temperatures. The use of catalyst allows a substantial temperature reduction to achieve workable reaction rates. The expense of platinum is noted and described as a motivation for the current work. The majority of work to identify active catalysts for this reaction was performed in the late 1970s and early 1980s <15– 18> and is best summarized by O’Keefe et al. <15>. Different catalytic systems were found effective, in particular the platinum group metals supported on activated carbon or g-Al2O3 showed very good performance. Recent work explored platinum– ceria catalysts for the hydrogen production reaction <19,20>. The limited availability of noble metal makes it necessary to develop less expensive catalysts based on nonprecious metals and supports. Some authors proposed activated carbon <21> and Ni-supported catalysts <15,22,23> for HI catalytic decomposition. The cost savings resulting from the use of non-precious metals may be an advantage in the design of a plant of large size. For the record, the Ni/CeO2 catalyst is very versatile, and widely investigated in a number of important reactions. Nickel is a cogener of platinum and palladium. The latter element is available in huge quantities from used nuclear fuels and its recovery from these sources is an active area of nuclear chemistry research. Here is a brief review of the experimental procedure used in the Chinese laboratory to investigate the catalyst: 2.2. Catalysts characterization The thermokinetics characteristic of the Ni/CeO2 gel was investigated on a thermo-gravimetric apparatus (air atmosphere, 30 ml/min and 30 _C/min) with an online infrared spectrum analyzed (TG-FTIR). The specific surface area, average pore diameter and pore olume were determined by Brunauer–Emmett–Teller (BET) method with a Quantachrome NOVA instrument using N2 as adsorbent. The X-ray diffraction analysis (XRD) was performed on a D/max 2550PC. The X-ray tube was operated at 40 kV and 200 mA. The -ray powder diffractogram was recorded at 0.02_ intervals in the range 20_ _ 2q _ 90_ with 0.3 s count accumulation per step. The High Resolution Transmission Electron Microscopy (HRTEM) picture was performed on a JEM-2010 (HR). Temperature programmed reduction (TPR) experiment was carried out on a TPR catalytic surfaces analyzer. The samples were heated under flowing H2 (5% in N2, 20 ml/min) from room temperature to 800 _C (10 _C/min). 2.3. Activity measurement The catalytic decomposition of HI was performed at 300–550 oC in a quartz tube with the diameter of 18 mm. The mixture composed of 1 g catalyst powder and appropriate volume of coarse quartz particles was loaded in the tube. As shown in Fig. 1, the 55 wt.% hydriodic acid (HI solution) was pumped using a BT00-50Mperistaltic pump into an evaporator where the acid vaporized and mixed with nitrogen gas and then the mixture was introduced into the quartz tube. Flow rate of the nitrogen gas and HI was maintained at 60 ml/min and 0.7 ml/min. The reaction was carried out at atmospheric pressure. All the gases from the quartz tube, except hydrogen and nitrogen gas, were trapped in a spiral condenser and few residual HI and I2 were sequentially trapped in two scrubbers. Hydrogen was analyzed by a gas chromatograph. Some remarks from the conclusion. 4. Conclusions. In this study, the Ni/CeO2 catalysts with different calcinations temperatures have been tested to evaluate their effect on HI decomposition in sulfur–iodine cycle. TG-FTIR, BET, XRD, HRTEM and TPR were performed for catalyst characterization. It was found that the Ni2þ ions could be inserted into the ceria lattice. This brought about the strong interaction between Ni and CeO2, especially at high calcination temperature and the generation of oxygen vacancies. Oxygen vacancy and the surface site played the important role in catalytic surface reaction. The two active sites were well-balanced on Ni/Ce700 catalyst, which resulted in the best activity as well as good stability. All the results provided this material with a potentialto be used in sulfur–iodine cycle for hydrogen production This is certainly not the only approach to improving this reaction by the way, an interestingly another interesting approach involves the use of nickel via decomposition of a nickel iodide intermediate. Have a wonderful Memorial Day Weekend, and try to do some memorializing. Famous Anti-nuke Amory Lovins describes his revenue sources: Mr. Lovins’s other clients have included Accenture, Allstate, AMD, Anglo American, Anheuser-Busch, Bank of America, Baxter, Borg-Warner, BP, HP Bulmer, Carrier, Chevron, Ciba-Geigy, CLSA, ConocoPhillips, Corning, Dow, Equitable, GM, HP, Invensys, Lockheed Martin, Mitsubishi, Monsanto, Motorola, Norsk Hydro, Petrobras, Prudential, Rio Tinto, Royal Dutch/Shell, Shearson Lehman Amex, STMicroelectronics, Sun Oil, Suncor, Texas Instruments, UBS, Unilever, Westinghouse, Xerox, major developers, and over 100 energy utilities. His public-sector clients have included the OECD, the UN, and RFF; the Australian, Canadian, Dutch, German, and Italian governments; 13 states; Congress, and the U.S. Energy and Defense Departments.
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 William Schwartz, (1896-1977) Russian-American, 1934. Oil on Canvas. At the Michener Museum, Doylestown, PA.
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From my personal perspective, hydrogen is useless as a commercial retail fuel, and talk of hydrogen cars, (or HYPErcars) is just garbage thinking, and is only credible for those people credulous enough to read books like Winning the Oil Endgame, which bristles with platitudes, hand waving, wishful thinking and other useless delusional consumer car CULTure tripe. (It would seem that the Gulf of Mexico didn't "win the oil endgame," since the only ending going on here is the end of some ecosystems, and possibly species.) That said hydrogen is very useful as an industrial captive fuel, and could be useful for phasing out the dangerous fossil fuel oil, the destructive potential of which is being obviated yet again, not that anyone seems to recognize the critical importance of phasing it out. The most useful tool for phasing out dangerous fossil oil is the miracle fuel DME, which is actively being commercialized in Asia. It is readily accessible whenever one has hydrogen via the hydrogenation of carbon dioxide.
The spontaneous thermal decomposition of water to give hydrogen and oxygen is only thermodynamically favorable at temperatures in excess of 4000C, still impracticable from a materials science standpoint. Even were it possible to achieve these temperatures industrially, one would still face the spontaneous recombination of the resultant hydrogen and oxygen as the mixture cooled. To avoid these limitations many thermochemical cycles that operate at much lower temperatures to produce hydrogen have been extensively investigated and refined. These include the UT-3 (CaBr2) cycle, Ferrite Cycles, Tin Oxide cycles, Manganese Cycles, Cerium based cycles, and Germanium cycles. I have a cute cycle of this type of my own, but won't discuss it here. Many of these cycles all have merits and demerits, the main demerit for many of them being the necessity for solids handing. Continuous systems are ideal from an economic standpoint, and continuous systems generally rely on fluid phases, either gas, liquid or supercritical fluid, which is neither gas nor liquid but has properties of both. However the most famous cycle, by far, is the "SI" cycle, or sulfur iodine cycle which consists of the following series of reactions: 1) H2SO4 -> SO3 + H2O 2) SO3 -> 1/2 O2 + SO2 3) I2 (l) + SO2 (g) + 2H2O (l) → 2HI (l) + H2SO4. 4) 2HI -> H2 + I2. The net reaction is the decomposition of water to give hydrogen and oxygen, this in such a way as the two gases are physically separated. Reaction 3 is known as the Bunsen reaction. It is exothermic. All of the other reactions are endothermic and require the input of various amounts of heat. Reactions 1 and 2 are often combined (and they are expected to be accomplished in a single reactor and thus this is justified) into a single reaction which is written like this: (5) H2SO4 -> 1/2 O2 + SO2 + H2O Reaction 5, an exothermic reaction, involves fairly high temperatures, the highest in the SI cycle, typically around 800C - 900C. Although this reaction temperature is easily obtainable in industrial systems, it would be ideal to reduce the temperature to a lower level to assure system life, particularly because sulfuric acid is a corrosive compound, although not so corrosive that it isn't widely distributed for use in the car CULTure. A recent paper in the scientific literature discusses this approach through the use of catalysts to lower the temperature at which the reaction takes place. Here is the abstract of the paper: International Journal of Hydrogen Energy 33 (2008) 319 – 326 The title of the article, which is written by Indian chemists, is "Catalytic decomposition of sulfuric acid on mixed Cr/Fe oxide samples and its application in sulfur–iodine cycle for hydrogen production." Here are some choice excerpts: Given the prospect of a lack of fossil resources and limitations on the release of greenhouse gases, only water and biomass are the two candidate raw materials for hydrogen production. The two processes that have the greatest likelihood of successful massive hydrogen production using water as the raw material are electrolysis and thermochemical cycles. The thermochemical cycles are processes where water is decomposed into hydrogen and oxygen via chemical reactions using intermediate elements which are recycled. The sum of all the reactions is equivalent to the dissociation of the water molecule. Because they only use heat without having it to convert it to electricity, these cycles have the potential of a better efficiency than electrolysis and hence have the potential to significantly reduce the cost for hydrogen production from water. So far numerous cycles <1–4> have been investigated (almost 200), among them sulfur–iodine (S–I) cycle, originally proposed by General Atomics <5>, is being looked at as a promising process for hydrogen production due to its higher efficiency(∼56%). Further on we here a description of the limitation I described above: Sulfuric acid can be decomposed with or without a catalyst, while the decomposition of SO3 has been known to be a catalytic reaction. Apparently only a few and partial kinetic data for the global process can be found in the literature <6–8>. Some indications regarding the kinetics of sub-reaction (Eq. (4)) can be found in some theoretical and experimental studies of the reverse reaction <9–11>. For the sub-reaction (5) some incomplete and scanty data are available even in the presence of catalytic agents. In order to decrease the operating temperature, transition metals or their oxides seem to be interesting candidates as sulfuric anhydride decomposition catalysts <12>. The activity of metal oxides for the sulfuric acid decomposition was studied in the range of 600–950 ◦C in a fixed bed reactor and the order of activity was reported as follows: Pt ≈ Cr2O3 > Fe2O3 >CeO2 >NiO>Al2O3 <13>. However, the ever rising demand and increasing cost make noble metals less preferred for the above applications. Recently, oxides samples of Fe2O3 and Pd–Ag alloy have been tested to evaluate their effect on dissociation efficiency by Barbarossa et al. <14>. Dokiya et al. <6> reported on the use of several metal oxides as catalysts for sulfuric acid decomposition but only at two temperatures, viz 1093 and 1133 K. Although simple oxide catalysts are active and can be a substitute for noble metal catalysts but their limitations of thermal instability, and sintering effects on repeated use, prevent them from the actual application... ...With an objective to develop certain Cr substituted Fe2O3-based compositions which may serve as structurally stable and catalytically active materials for the sulfuric acid decomposition reaction, present study was taken up in which the Fe2(1-x)Cr2xO3 samples were synthesized and characterized by powder X-ray diffraction (XRD), surface area measurements and vibrational spectroscopy. The redox behavior and reproducibility toward repeated reduction and oxidation cycles have been monitored by recording multi temperature-programmed reduction/oxidation (TPR/TPO) cycles. The catalytic activity was evaluated for sulfuric acid decomposition in temperature range of 400–800 ◦C as a function of Cr-substitution. The SO2- present in effluent gases was identified and monitored by IR and mass spectrometry. The phase stability of used samples was analyzed by XRD and IR. Then there's a whole bunch of stuff about making catalysts, and a number of technical descriptions of physical measurements of its properties under various conditions, as well as putative chemical mechanisms for the operations of the catalysts. The best catalyst was a non-stoichiometric catalysts whose formula can be expressed Fe1.8Cr0.2O3. This catalyst is reported to have driven the reaction to approximately 90% completion at a temperature of 750C. All Fe2(1-x)Cr2xO3 amples facilitated the thermal decomposition of sulfuric acid in temperature range of 550–800oC much lower as compared to uncatalysed reaction. The maximum conversion was obtained at 800 ◦C with the onset of formation of SO2 at 600 ◦C. Solid solution of 10% Cr substitution in Fe2O3 lattice has not only enhanced reproducibility toward repeated reduction–oxidation cycles but also prevented the deactivation of the catalyst during use in sulfuric acid decomposition reaction. Fe1.8Cr0.2O3 was found to be promising active and stable mixed oxide catalyst for the above reaction. The amount of SO2 formed was found to increase with increase in reaction temperature as confirmed from IR and mass spectrometry. The presence of XRD and IR lines due to sulfate species on the used samples confirms their formation and decomposition as the rate determining step in the mechanism of SO3 → SO2 conversion on oxides. Cool, or hot, or something.
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Halide Salt Solubility in Supercritical Water Relevant to the Destruction of Halogenated Pollutants.
Supercritical states exist at temperatures and pressures at which there is no distinction between the gas phase and the liquid phase. Usually it is recognized by the disappearance of a heat of vaporization between liquid and gas phases. At atmospheric pressure, when water boils at 100C, heat is added to the system without a change in temperature being recorded. The energy being added to the system has no effect on temperature, as anyone who cooks observes.
Water in this different phase, supercritical water, has very different properties. It is very acidic relative to normal phase water either as liquid or steam, and organic molecules, including many pollutants are far more soluble in it, while, conversely salts, readily soluble in liquid water are not soluble in supercritical water. One can also have fire in supercritical water, as oxygen is miscible with water in the supercritical state. A relatively recent paper in the scientific literature discusses the problem of insoluble salts generated when the serious pollutants represented by organohalide compounds such as PCB’s, chlorocarbons and other toxic compounds are destroyed in a supercritical halide matrix, which offers many environmental advantages with respect to traditional methods of destruction such as incineration. Here is the abstract of the paper. J. of Supercritical Fluids 50 (2009) 1–5 Supercritical water oxidation (SCWO) technologies have been applied to decompose the toxic organics <1,2>, such as dioxin and poly-chloro-biphenyl (PCB), to CO2 and H2O. In these processes, hydrogen halides such as hydrochloric acid are produced and cause remarkable corrosion of reactor. Alkalis are added as the neutralization reagent in order to prevent the corrosion and metal chlorides are produced. These metal chlorides in supercritical water are precipitated in the reactor or lines because of the very low solubilities of the metal chlorides in supercritical water. The effective discharges of the metal chlorides from the system are required. Therefore, it is important for the development of the supercritical water oxidation processes to understand the solubilities of metal chlorides in supercritical water and the phase behavior for supercritical water +metal chloride systems. The solubilities of sodium chloride in water vapor at high temperatures and pressures have been reported by some research groups <3–6>. Bischoff et al. <3> measured the solubilities of sodium chloride in sub- and supercritical water at the vapor–liquid equilibrium regions by a static method. One may reasonably ask about the experimental details, which are somewhat problematic since one can not use in general, glass systems to make these determination. (A device which does allow for the visual characterization of these compounds is the diamond anvil, which uses diamond as the window, because diamond is able to withstand high pressures and temperatures, which are in fact, the conditions at which diamond is formed. However diamond anvils generally are microscale and are not – yet- useful for macroscopic property determinations.) Here’s a brief description of the apparatus used from the paper: 2.2. Apparatus and procedure A flow type apparatus was used for the measurements of the solubilities for lithium chloride and calcium chloride in water vapor at high temperatures and pressures. The experimental apparatus and procedure were quite similar to those in a previous work <9>. The detailed descriptions of the apparatus and operating procedures were given in the previous work. The apparatus and procedures are only briefly described here. An equilibrium cell was made of Hastelloy C. The inside diameter and volume were about 12mm and 10 ml, respectively. The cell was set in an air bath in which the temperatures were controlled within ±0.5 K. In the equilibrium cell, 2 g of lithium chloride or calcium chloride was introduced beforehand with the solubility measurements. This initial mass of metal chloride was larger than those in the case of NaCl and KCl in the previous work <9>. The equilibrium cell in the air bath was heated up to the desired temperatures. Pure water was supplied by a feed pump. A back pressure regulator was used for the control of the pressures in the system. The pressures in the system were maintained within ±0.05MPa. The pressurized water was heated through a preheating coil and supplied to the equilibrium cell. At the outlet of the cell, pure water was also supplied to the outlet of the cell in order to avoid the precipitations of metal chlorides. Water vapor passed through the cell was decompressed at an expansion valve. The trapped samples were analyzed by ion chromatography (JASCO Co.,Ltd.). The cation concentrations were obtained from the analysis. The solubilities of metal chlorides in water vapor were determined from the cation concentrations of metal chlorides and the flow rates of water measured at the sampling unit. The results of the work were quite interesting. For some ions, lithium and calcium, it was possible to actually increase the solubility of ions by increasing temperature. The conclusion of the paper is given here: The solubilities of lithium chloride and calcium chloride in water vapor were measured from 623 to 673 K and from 6.0 to 14.0 MPa by a flow method. At constant pressure, the solubilities of lithium chloride and calcium chloride increase with temperature increase unlike the case of sodium chloride and potassium chloride. It is though that the solubility behavior is resulted from the difference of the phase states, vapor–liquid equilibria for lithium chloride and calcium chloride and vapor–solid equilibria for sodium chloride and potassium chloride. The correlation model for the solubilities of the metal chlorides in water vapor was developed newly in consideration of the ionization and hydration of the metal chlorides. For the metal chlorides with monovalent cations, the hydration numbers in the correlation model increase with the radii of cations. Calcium chloride gives the large hydration number compared with those of metal chlorides with monovalent cations. The correlated results are in good agreement with the experimental data for the four metal chlorides. This has relevance to catalytic systems that may have import beyond the mere destruction of problem compounds. This is perhaps an esoteric bit of business, but may be of interest to environmental engineers and scientists.
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Reference Data Source For Photodissociation of Some Small Gas Molecules of Environmental Importance.
For anyone who, having a scientific bent, would like to know the ionization energies and photon cross sections of molecular pollutants like carbon dioxide, nitrous oxide, NO2, SF6, carbon monoxide, etc, etc, here's a cool reference for you:
J.Phys.Chem.Ref.Data.Vol.17.Issue.1.1988.1-144 Typical maxima for many such molecules undergoing photoionization are unsurprisingly in the short wave length UV and in the X-Ray region. When I was a young man, I used to love to look at data tables and graphs all evening for various systems. I haven't done it as much in recent years, but it's a fun to do it again. Esoteric maybe, but cool, and for environmental scientists and engineers, of some practical interest.
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 1862 Lord Frederic Leighton (1830-1896) British
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The scientific paper I will reference today comes from the "ASAP" on line version of the journal Environmental Science and Technology, a publication of the American Chemical Society, one of the greatest and oldest scientific organizations in the world.
Sources and Deposition of Polycyclic Aromatic Hydrocarbons to Western U.S. National Parks PAH's are "polycyclic aromatic hydrocarbons," and refer to a wide variety of molecules that are produced in combustion situations. They are constituents of the dangerous fossil fuel waste dumped routinely in earth's atmosphere, and are also involved in biomass combustion. (Biomass combustion and dangerous fossil fuel combustion cause well more than one million deaths on this planet each year according to the World Health Organization.) If one refers to the abstract, one sees that Cs137 is used as a soil flow marker in the science in this paper. The science involved in this determination is nuclear science. I explained how this particular aspect of nuclear science works on another website (interestingly, one run by anti-nukes). Every Cloud Has A Silver Lining, Even Mushroom Clouds: Cs-137 and Watching the Soil Die. Anyway, about the PAH's in National Parks, some excerpts: The U.S. National Parks contain exceptionally diverse ecosystems with unique plant and animal species (1), and U.S. government regulations, such as the Organic Act, Clean Air Act, Wilderness Act, and the National Environmental Policy Act, have instated the U.S Department of the Interior’s National Park Service as steward of U.S. National Parks (2). In 2002, the U.S. National Park Service initiated the Western Airborne Contaminant Assessment Project (WACAP) to investigate the deposition of semivolatile organic compounds (SOCs), including polycyclic aromatic hydrocarbons (PAHs), to remote ecosystems in western U.S. National Parks (2, 3). PAHs are produced from the incomplete combustion of fossil fuels and biomass decay/burning and some PAHs pose risks to human and ecosystem health because of their toxicity (4, 5). Hafner et al. reported that atmospheric PAH concentrations are positively correlated with human population density (5). PAHs are deposited to remote high-elevation and/or high-latitude ecosystems via air-surface exchange, dry deposition, and/or wet deposition in the form of snow and rain (6-8). As a result of colder temperatures in these ecosystems, PAH degradation and revolatilization to the atmosphere is decreased, potentially resulting in elevated concentrations (6). The objectives of this study were to (1) determine the spatial and temporal PAH distribution patterns using PAH concentrations and fluxes measured in seasonal snowpack, lichen, and sediment cores collected from 14 U.S. national park lake catchments and (2) identify potential PAH sources to these remote ecosystems using the PAH profile and isomer ratios. One can in fact tie the nature of combustion sources that deposit carcinogens on natural parks to, for instance, certain species of plants (usually trees) burned in biomass burning activities. As mentioned in the text cited above another means of doing this is with isotopic analysis, also a feature of nuclear science. The PAHs measured included acenaphthylene (ACY), acenaphthene (ACE), fluorene (FLO), phenanthrene (PHE),anthracene (ANT), fluoranthene (FLA), pyrene (PYR), retene, benzoanthracene (BaA), chrysene and triphenylene (CT), benzofluoranthene (BbF), benzo By the way the analytical chemistry of determining these compounds, usually by GC/MS is very expensive. The analytical standard set for the EPA method costs big bucks, never mind the instrument. Rainier and Olympic are both less than 100 km from Seattle’s metropolitan area where more than 3 million residents live with 150 km of these national parks (Figure S1). Olympic is located west of Seattle, while Rainier is located southeast of Seattle (Figure S1). In Olympic, Hoh Lake is located on the northwest Pacific Coast side, while PJ Lake is located on the northeast Puget Sound side... ...The PAH profile of coal, gasoline, and diesel combustion sources have been identified (19). The PAH profile for the Seattle metropolitan area is dominated by 3-ring PAHs, primarily PHE and FLA, because these are the primary PAHs emitted from vehicular traffic (19). The Rainier annual snowpack PAH profiles, from both Golden Lake and LP19 catchments, were very similar and were dominated by higher molecular weight PAHs (5 and 6 ring PAHs) (Figure S17E). This suggests that the Seattle metropolitan area is not the only source of PAHs to Rainier and may include emissions of higher molecular weight PAHs from a coal-fired power plant ∼85 km west of Rainier and/or trans-Pacific transport (20). Not to worry. Amory Lovins has found marks, um, I mean "investors" who have helped him to develop the hydrogen HYPErcar that will be in showrooms by 2005. So, um, don't worry about the car culture. It will be swell by 2050, after many of the people here are dead, but who wants to get techincal? Speaking of Amory Lovins, it appears that Canadian dangerous fossil fuel mining procedures, involving "clean" dangerous natural gas, has an effect on the distribution of PAH's in American National Parks. Oil and gas wells have been drilled in southwest Alberta, Canada, located within 150 km of Glacier on the east side of the Continental Divide, since the 1920s (24). Waste gases from these wells are flared for safety reasons during well testing (24). In 2000, approximately 5300 gas flares were operational in Alberta and PAH concentrations in air near the flares were similar to those of large-scale industrial areas (25). Since 1983, the number of oil and gas flares in Alberta has increased from 3600 to 15,700, with a doubling time of 9.5 yrs (r2)0.72, p < 0.001) (26). Three hundred and fifty well rigs were located within 150 km of Glacier in June 2007 and 97% of these were located east of the Continental Divide (26). The increase in the number of oil and gas flares over time may explain, in part, the ΣPAH flux doubling time (48.9 yrs) measured in Oldman Lake. Wow, the number of oil and gas flares is going up! And this at a time when wind and solar are saving us. What a surprise. I had something to say about dangerous fossil fuel mining processes in Canada in another thread on this site. Profile of a Company That Funds the Famous Anti-nuke Amory Lovins: Suncor. But to finish up here: A dam-powered Soderberg aluminum smelter became operational in Columbia Falls, MT in 1955 (27). The smelter resides on the Flathead River, approximately 10 kmsouthwest of Glacier on the west side of the Continental Divide and approximately 45 km southwest of Snyder Lake (Figures S19 and S20). The outflow from Snyder Lake forms a tributary to the Flathead River. Soderberg aluminum smelters can be significant local sources of hydrogen fluoride and PAHs (28, 29) because of the use of coal tar in the smelting process. According to U.S. EPA records, this smelter released, on average, ∼65 tons of hydrogen fluoride per year from 1999 to 2004 and, on average,∼14 tons of PAH per year from 1999 to 2005 (30). Don't worry, the aluminum smelter is powered by so called "renewable energy" and therefore the carcinogenic PAH's from it don't count. Speaking of so called "renewable energy," The 2003 and 2004 Snyder Lake catchment snowpack PAH ratios were similar to the ratios calculated from the Soderberg aluminum smelter emissions, while the Oldman Lake catchment snowpack PAH ratios were similar to the ratios calculated from petroleum combustion and pine wood combustion in residential fireplaces (Figures S21 and S22). The retene flux, a marker for softwood combustion, in the 2003 Oldman Lake snowpack (1.5 μgm-2 y-1) was similar to that of Snyder Lake catchment (1.2 μgm-2 y-1). The retene flux is likely the result of wood combustion for heating and/or manufacturing (23). Um, delicious. The bold is mine. To estimate the relative contributions of different PAH sources to Glacier,was assumed that, during the winter months when “Going-to-the-Sun Road” was closed, automobile traffic through the park was 0% (relative to summer) and wood combustion from home heating was 100% (relative to summer). The 2003 (when the smelter was operating at 60% capacity) Snyder Lake catchment snowpack IcdP/(IcdP+BeP) and IcdP/(IcdP+BghiP) ratios were slightly higher than the same ratios measured from aluminum smelter emissions (29, 38), but less than the same ratios measured from wood combustion in residential fireplaces (Figure S21) (37). This suggests that both of these sources contribute PAHs to the Snyder Lake catchment in winter... ...Using the same simple numerical solution for the 2004 Snyder Lake snowpack (smelter operating at 20% capacity), we roughly estimate that approximately 71% of the PAHs in the 2004 Snyder Lake snowpack originated from the smelter and approximately 29% originated from wood combustion. Have a nice evening.
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You can dump, for free, all the dangerous fossil fuel waste you want.
You don't need to contain it for eternity. It can kill freely eliciting no comments from any one. Thank you, Amory Lovins. We love you. Famous Anti-nuke Amory Lovins describes his revenue sources: Mr. Lovins’s other clients have included Accenture, Allstate, AMD, Anglo American, Anheuser-Busch, Bank of America, Baxter, Borg-Warner, BP, HP Bulmer, Carrier, Chevron, Ciba-Geigy, CLSA, ConocoPhillips, Corning, Dow, Equitable, GM, HP, Invensys, Lockheed Martin, Mitsubishi, Monsanto, Motorola, Norsk Hydro, Petrobras, Prudential, Rio Tinto, Royal Dutch/Shell, Shearson Lehman Amex, STMicroelectronics, Sun Oil, Suncor, Texas Instruments, UBS, Unilever, Westinghouse, Xerox, major developers, and over 100 energy utilities. His public-sector clients have included the OECD, the UN, and RFF; the Australian, Canadian, Dutch, German, and Italian governments; 13 states; Congress, and the U.S. Energy and Defense Departments.
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