Reactive adsorption

To summarize, one can say that the electrochemical performance of CNT electrodes is correlated to the DOS of the CNT electrode with energies close to the redox formal potential of the solution species. The electron transfer and adsorption reactivity of CNT electrodes is remarkably dependent on the density of edge sites/defects that are the more reactive sites for that process, increasing considerably the electron-transfer rate. Additionally, surface oxygen functionalities can exert a big influence on the electrode kinetics. However, not all redox systems respond in the same way to the surface characteristics or can have electrocatalytical activity. This is very dependent on their own redox mechanism. Moreover, the high surface area and the nanometer size are the key factors in the electrochemical performance of the carbon nanotubes. 

SURFACE. In physical chemistry the area of contact between two different phases or states of matter, e.g., finely divided solid particles and air or other gas (solid-gas) liquids and air (liquid-gas) insoluble particles and liquid (solid-liquid). Surfaces are the sites of tire physiochemical activity between the phases that is responsible for such phenomena as adsorption, reactivity, and catalysis, The depth of a surface is of molecular order of magnitude, The term interface is approximately synonymous with surface, but it also includes dispersions involving only one phase of matter, i.e., solid-solid or liquid-liquid,... 

Reactive distillation Membrane-based reactive separations Reactive adsorption Reactive absorption Reactive extraction Reactive crystallization... 

Whilst the development of new adsorbents on monolithic [62] or fibrous supports [63] to cut pressure drops, of high-capacity metal organic frameworks (MOFs) [64], or of highly selective molecularly imprinted polymers (MIPs) [65], is certainly beneficial for the realization of novel adsorptive reactive concepts, the serendipity of catalytic chemistry and the accompanying adsorption process remains the crucial factor for the success or otherwise of an adsorptive reactor. Thus, although a healthy degree of skepticism is appropriate when assessing the suitability of an adsorptive... 

The first mechanistic problem of importance is to find out the nature of the electroactive species for the electrode reaction of interest. Once this has been established, the way is open for mechanistic studies of a higher order, such as the reaction sequence, the role of adsorption, reactivity, and so on. 

Accurate predictions of the transport of As in groundwater requires site specific data to model adsorption/desorption reactions. In complex mixtures of minerals, it may not be possible to quantify the adsorption properties of individual minerals. Therefore, it has been suggested that adsorption properties of composite materials should be characterized as a whole (Davis and Kent, 1990). Previously published data for adsorption by pure mineral phases such as the surface complexation database for adsorption by ferrihydrite (Dzombak and Morel, 1990) can be a useful starting point for modeling adsorption of solutes in groundwater however, these equilibrium constants may not reflect the adsorption properties of composite oxide coatings on aquifer solids. For example, incorporation of Si, and to a lesser extent, A1 into Fe oxyhydroxides has been shown to decrease adsorption reactivity towards anions (Ainsworth et al., 1989 Anderson and Benjamin, 1990 Anderson et al, 1985). Therefore, equilibrium constants will likely need to be modified for site-specific studies. 

The properties of the catalyst surface such as, for instance, work function, heat of adsorption, reactivity of the adsorbed species, markedly... 

Dichloroethenes (DCEs) are good candidates for delineating the behaviour of simple unsaturated chlorinated species with metal surfaces and, in particular, they provide a means for comparing and contrasting the reactivity patterns of different isomers. Previous work has studied the adsorption and reaction of chloroethenes on Pt(l 11), Pt(lOO), Pd(l 10), Cu(lOO) and Cu(llO) . In this paper, the adsorption, reactive transformation and product evolution of c/5-l,2-dichloroethene on Cu(llO) are reported and compared particularly with related studies on the trans isomer. This work represents part of an ongoing effort to characterise and understand the interactions of a series of chlorinated... 

Zeolites can be classified in many ways. Two convenient methods are on the basis of pore size and chemical composition, that is, the Si/Al ratio. The pore diameter is determined by the size of the free apertures in the structure, which is dependent on the number of T atoms (T = Si or Al) that form the aperture. Table 10.1 summarizes some examples of zeolites based on pore size classification. It should be noted that the values typically reported in the literature are determined by crystallographic studies. While these numbers are good guides, it is important to note that the actual pore size depends on many factors, including temperature, firamework composition, and the type of extra-framework cations present in the zeolite. These factors can lead to subtle changes in effective pore sizes and subsequently large changes in material properties (adsorption/reactivity). 

Bench-scale experiments were performed in a 5-cm ID fluidized-bed reactor (FBR). These experiments were intended to 1) prepare carbon products with varying ash content, sulfur content, surface area, pore volume and production yield, 2) identify optimum conditions for producing activated carbon samples with desired properties for removal of various mercury species from utility flue gas, 3) evaluate the influence of inherent sulfur of the coal precursors on the mercury adsorption reactivity and capacity of the resultant activated carbon products, and 4) obtain scale-up date for producing larger quantities of carbon products in a pilot-scale FBR. 

Vaseoneelos, H. L., Camargo, T. R, Goncalves, N. S., Neves, A., Laranjeira, M. C. M., and Fa-vere, V. T. (2008). Chitosan cross-linked with a metal eomplexing agent Synthesis, characterization and eopper(II) ions adsorption. Reactive and Functional Polymers 6S, 572-579. 

There are other factors that need to be considered to make up a good paint, including pigment particle size, solubility of the pigment in the medium, media adsorption, reactivity with the medium, etc. There is so much more to color than meets the eye ... 

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