Research/test reactors

Nuclear reactor and generator at Argonne National Laboratory used primarily for research and development in testing reactor fuels as weU as for training. The generation from the unit is used for internal consumption. 

Bosch and co-workers devised laboratory reactors to operate at high pressure and temperature in a recycle mode. These test reactors had the essential characteristics of potential industrial reactors and were used by Mittasch and co-workers to screen some 20,000 samples as candidate catalysts. The results led to the identification of an iron-containing mineral that is similar to today s industrial catalysts. The researchers recognized the need for porous catalytic materials and materials with more than one component, today identified as the support, the catalyticaHy active component, and the promoter. Today s technology for catalyst testing has become more efficient because much of the test equipment is automated, and the analysis of products and catalysts is much faster and more accurate. 

Catalyst testing and evaluation have been revolutionized by computers, automated test reactors, and analytical methods. With modem equipment, researchers can systematically prepare and screen many catalysts in a short time and efftciendy deterrnine, not only the initial catalytic activity and selectivity, but also the stabiUty and the appearance of trace products that may indicate some new catalytic properties worthy of further development. 

Japan Atomic Energy Research Institute, High Temperature Engineering Test Reactor (HTTR), Technical Literature. 

FIGURE 17.27 Research into controlled nuclear fusion is being carried out in several countries. Here we see the Tokomak fusion test reactor at the Princeton Plasma Physics Laboratory. 

A growing number of research groups are active in the field. The activity of reforming catalysts has been improved and a number of test reactors for fuel partial oxidation, reforming, water-gas shift, and selective oxidation reactions were described however, hardly any commercial micro-channel reformers have been reported. Obviously, the developments are still inhibited by a multitude of technical problems, before coming to commercialization. Concerning reformer developments with small-scale, but not micro-channel-based reformers, the first companies have been formed in the meantime (see, e.g., ) and reformers of large capacity for non-stationary household applications are on the market. 

Van Santen [13] identifies three levels of research in catalysis. The macroscopic level is the world of reaction engineering, test reactors and catalyst beds. Questions concerning the catalyst deal with such aspects as activity per unit volume, mechanical strength and whether it should be used in the form of extrudates, spheres or loose powders. The mesoscopic level comprises kinetic studies, activity per unit surface area, and the relationship between the composition and structure of a catalyst and its... 

Fusion has already been achieved in several devices, but not beyond the break-even point, where the amount of energy produced is the same as the amount consumed. Much basic research is still required and is the focus of a number of international collaborative efforts. As discussed in Chapter 4, foremost among these efforts is the International Thermonuclear Experimental Reactor (ITER), which will be a scale-up of the Princeton Tokamak Fusion Test Reactor shown in Figure 19.17. 

Americium was isolated first from plutonium, then from lanthanum and other impurities, by a combination of precipitation, solvent extraction, and ion exchange processes. Parallel with the separation, a vigorous program of research began. Beginning in 1950, a series of publications (1-24) on americium put into the world literature much of the classic chemistry of americium, including discussion of the hexavalent state, the soluble tetravalent state, oxidation potentials, disproportionation, the crystal structure(s) of the metal, and many compounds of americium. In particular, use of peroxydisulfate or ozone to oxidize americium to the (V) or (VI) states still provides the basis for americium removal from other elements. Irradiation of americium, first at Chalk River (Ontario, Canada) and later at the Materials Testing Reactor (Idaho), yielded curium for study. Indeed, the oxidation of americium and its separation from curium provided the clue utilized by others in a patented process for separation of americium from the rare earths. 

The fuel for water-cooled powder reactors is enriched to contain 2-4% U-235. Higher enrichments up to 93% U-235 are used in fuels for fast breeder reactors, HTGRs, and certain research and test reactors. 

In the United States there are at present 61 research and testing reactors with a power of 100 KW or greater, operated by universities, state and national laboratories, and industries in 25 states, most of which can be used for activation analysis ( ). Many analysts work only with long-lived activation products and thus need not be present at the reactor to perform Irradiations. The equipment required for gamma-ray assay s a detector and pulse-height analyzer s is comparable in cost and complexity with that needed for other modern analytical methods. 

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