Solids mixing characterization

Conventional electrolytes applied in electrochemical devices are based on molecular liquids as solvents and salts as sources of ions. There are a large number of molecular systems, both pure and mixed, characterized by various chemical and physical properties, which are the liquids at room temperatures. This is the reason why they dominate both in laboratory and industrial scale. In such a case, solid salt is reacted with a molecular solvent and if the energy liberated during the reaction exceeds the lattice energy of the salt, the solid is liquified chemically below its melting point, and forms the solution. Water may serve as an example of the cheapest and most widely used molecular solvent. 

Vega, C., Kim, E.H.J., Chen, X.D., and Roos, Y.H. (2005). Solid-state characterization of spray-dried ice cream mixes. Coll. Surf. B Biointerfaces, 45, 66-75. 

In the pyrolysis processes, a thermal degradation occurs between 400 and 600°C in the complete absence of oxygen. These processes are characterized by the indirect heating of the material through the furnace wall (or pipes). The pyrolitic products, the solid (mix of char metals and mineral matter) and the hot gases (condensable and noncondensable mixture), are collected. Their relative proportions depend on the nature of the material, the applied technology and the pyrolysis conditions, i.e. temperature, pressure, heating rate, etc. The reductive atmosphere of the furnace is mainly a function of the pyrolitic gas composition. 

The solids residence time distribution (RTD) in the riser may thus be important in non-catalytic gas-solid reactions, as in a combustor, since this distribution characterizes the degree of solids mixing and provides information about the physical properties of the solid particles in the riser [14]. Moreover, lateral mixing and internal recirculation of solids in a CFB combustor are necessary to maintain uniform temperatures over the entire length of the riser. Hence, lateral and longitudinal mixing is advantageous in a CFB combustor. 

The electrochemical reduction of a solid compound characterized by mixed ionic/ electronic conductivity, immobilized on an electrode surface and in contact with an electrolyte solution, has been further studied on a theoretical basis [26]. Here, the coupled uptake or expulsion of electrons from the electrode and of cations from the electrolyte solution according to... 

The thermodynamic behaviour of polymer solutions has been the subject of extensive study, partly because of the importance of surface coatings such as lacquers and paints, and partly because it is essential to understand the behaviour of polymers in solution in order to quantitatively characterize the polymers and copolymers. Furthermore, it is also not possible to understand the behaviour of polymer-polymer systems (blends and alloys) without some understanding of polymer-solvent systems. There is a close relationship between the way in which amorphous solids mix and the behaviour of polymers in solution polymer solutions are much more amenable to experimental measurements. 

Busca, G., Lorenzelli, V. and Sanchez Escribano, V. (1992). Preparation, solid-state characterization and surface chemistry of high-surface area NixAl2 2 c03 2x mixed oxides, Chem. Mater., 4, pp. 595-605. 

The ability to characterize the object or system of interest is essential for any undertaking. Solids mixing is no exception the object of interest here is a mixture of particulate materials. 

Numerous research problems of practical and industrial importance and of theoretical and academic interest await solution in the preparation, characterization and application of ordered mixtures and composition-stable mixtures. Scant attention is paid here to these subjects because they are regarded as being outside the scope of bulk-solids mixing in the conventional sense, which usually is concerned with mixing and blending of free-flowing particles and powder in relatively large quantities. 

It is worth reiterating that much remains to be done to expand our understanding of the mechanisms of solids mixing and to estimate their rates to characterize the quality of resultant mixtures to design and scale-up mixers and to determine suitable operating conditions of the mixers. To accomplish these, we should resort increasingly to modem paradigms such as those based on fiactals, chaos, computer-aided particle simulation, and expert systems (see, e.g., Kaye [5], Fan et al. [7,22], Tsuji et aL [23]). 

The difficulties in dealing with these fundamental solid behaviors were aptly characterized as the metallurgical mud by Walsh and Taylor [84T01]. It has proven to be a difficult task to extricate shock-compression science from the metallurgical mud. Mixing of chemical ooze into the metallurgical mud has now further clouded our scientific knowledge of the processes. 

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