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Chemical oxidation description

Technology Description Oxidation processes involve the conversion of organics to CO2, H2O, HCl, NO2 and SO3 or the conversion of inorganics to a more desirable form. For both organic and inorganic wastes, the function of chemical oxidation is to... [Pg.146]

The first example of organometallic chemistry from isolated, well-defined mononuclear Pd(ni) complexes was reported by Mirica in 2010 [85]. Organometallic Pd(III) complexes 30 and 31 were prepared by controlled bulk electrolysis of Pd(II) precursors 28 and 29, respectively (Fig. 17). Complex 33 was prepared by chemical oxidation of 32 with Fc". X-ray crystallographic analysis of 30, 31, and 33 revealed tetragOTially distorted octahedral cranplexes, consistent with the expected Jahn-Teller distortiOTi for mononuclear, low-spin Pd(III) complexes [6]. A combination of EPR spectroscopy and computational results suggests that the impaired electron resides in the orbital, consistent with the MO description of octahedral Pd(III) in Fig. 1. [Pg.138]

GRl (Gas Research Institute). 2000. Chemical Oxidation with or without LIV Enhancement Technology Description. Available on line at URL www.gri.org. [Pg.69]

To synthesize conducting polymers, there are a number of methods including electrochemical oxidation of the monomers, chemical s mthesis and some less common one such as enz5mie-catalyzed and photochemically initiated polymerization [22], PANl is usually S5mthesized by chemical or electrochemical polymerization in the aqueous acid media. The synthesized polymer is called an emeraldine salt. For bulk production, the chemical oxidation of aniline is the more feasible method. The limitation of this method is the poor processability of the obtained polymer due to its insolubility in common solvents, although it can be improved by using different dopants [25, 27]. There are some descriptions about these two methods as follows ... [Pg.12]

The definition above is a particularly restrictive description of a nanocrystal, and necessarily limits die focus of diis brief review to studies of nanocrystals which are of relevance to chemical physics. Many nanoparticles, particularly oxides, prepared dirough die sol-gel niediod are not included in diis discussion as dieir internal stmcture is amorjihous and hydrated. Neverdieless, diey are important nanoniaterials several textbooks deal widi dieir syndiesis and properties [4, 5]. The material science community has also contributed to die general area of nanocrystals however, for most of dieir applications it is not necessary to prepare fully isolated nanocrystals widi well defined surface chemistry. A good discussion of die goals and progress can be found in references [6, 7, 8 and 9]. Finally, diere is a rich history in gas-phase chemical physics of die study of clusters and size-dependent evaluations of dieir behaviour. This topic is not addressed here, but covered instead in chapter C1.1, Clusters and nanoscale stmctures, in diis same volume. [Pg.2899]

Quaternary structure (Section 27 22) Description of the way in which two or more protein chains not connected by chemical bonds are organized in a larger protein Quinone (Section 24 14) The product of oxidation of an ortho or para dihydroxybenzene denvative Examples of quinones include... [Pg.1292]

DCMA Classification and Chemical Description of the Mixed Metal Oxide Inorganic ColoredPigments, 2nd ed.. Metal Oxides and Ceramic Colors... [Pg.430]

Many different configurations of diffusion flames exist in practice (Fig. 4). Laminar jets of fuel and oxidant are the simplest and most well understood diffusion flames. They have been studied exclusively in the laboratory, although a complete description of both the transport and chemical processes does not yet exist (2). [Pg.518]

Ethylene oxide is sold as a high purity chemical, with typical specifications shown ia Table 14. This purity is so high that only impurities are specified. There is normally no assay specification. Proper sampling techniques are critical to avoid personal exposure and prevent contamination of the sample with trace levels of water. A complete review and description of analytical methods for pure ethylene oxide is given ia Reference 228. [Pg.463]

To fully understand the formation of the N13S2 scale under certain gas conditions, a brief description needs to be given on the chemical aspects of the protective (chromium oxide) Ci 203/(nickel oxide) NiO scales that form at elevated temperatures. Under ideal oxidizing conditions, the alloy Waspaloy preferentially forms a protective oxide layer of NiO and Ci 203 The partial pressure of oxygen is such that these scales are thermodynamically stable and a condition of equilibrium is observed between the oxidizing atmosphere and the scale. Even if the scale surface is damaged or removed, the oxidizing condition of the atmosphere would preferentially reform the oxide scales. [Pg.239]

A motor-driven compressor is used as an oxidation system for a chemical unit. The control scheme for this arrangement is shown in Figure 8-40(c). Description of the control blocks follows. [Pg.362]

Specific identity of a toxic chemical to be a trade secret, the notice to your customer(s) must contain a generic chemical name that Is descriptive of the structure of that toxic chemical. For example, decabromodiphenyl oxide could be described as a halogenated aromatic. [Pg.95]

Technology Description In-situ chemical treatment uses the same principles employed for above-ground chemical processes. Materials are added to neutralize, oxidize or remove contaminants in groundwater or soils in order to avoid digging or pumping of the contaminated waste above ground for... [Pg.148]

Theoretical models available in the literature consider the electron loss, the counter-ion diffusion, or the nucleation process as the rate-limiting steps they follow traditional electrochemical models and avoid any structural treatment of the electrode. Our approach relies on the electro-chemically stimulated conformational relaxation control of the process. Although these conformational movements179 are present at any moment of the oxidation process (as proved by the experimental determination of the volume change or the continuous movements of artificial muscles), in order to be able to quantify them, we need to isolate them from either the electrons transfers, the counter-ion diffusion, or the solvent interchange we need electrochemical experiments in which the kinetics are under conformational relaxation control. Once the electrochemistry of these structural effects is quantified, we can again include the other components of the electrochemical reaction to obtain a complete description of electrochemical oxidation. [Pg.374]

A knowledge of the concentrations of all reactants and products is necessary for a description of the equilibrium state. However, calculation of the concentrations can be a complex task because many compounds may be Imked by chemical reactions. Changes in a variable such as pH or oxidation potential or light intensity can cause large shifts in the concentrations of these linked species. Aggregate variables may provide a means of simplifying the description of these complex systems. Here we look at two cases that involve acid-base reactions. [Pg.89]

The purpose of this paper Is 1) to describe the electrochemistry of ferrl-/ferro-cyanlde and the oxidation of ascorbic at an activated glassy carbon electrode which Is prepared by polishing the surface with alumina and followed only by thorough sonlcatlon 2) to describe experimental criteria used to bench-mark the presence of an activated electrode surface and 3) to present a preliminary description of the mechanism of the activation. The latter results from a synergistic Interpretation of the chemical, electrochemical and surface spectroscopic probes of the activated surface. Although the porous layer may be Important, Its role will be considered elsewhere. [Pg.583]

The precise structural role played by the water molecules in these cements is not clear. In the zinc oxychloride cement, water is known to be thermally labile. The 1 1 2 phase will lose half of its constituent water at about 230 °C, and the 4 1 5 phase will lose water at approximately 160 C to yield a mixture of zinc oxide and the 1 1 2 phase. Water clearly occurs in these cements as discrete molecules, which presumably coordinate to the metal ions in the cements in the way described previously. However, the possible complexities of structure for these systems, which may include chlorine atoms in bridging positions between pairs of metal atoms, make it impossible to suggest with any degree of confidence which chemical species or what structural units are likely to be present in such cements. One is left with the rather inadequate chemical descriptions of the phases used in even the relatively recent original literature on these materials, from which no clear information on the role of water can be deduced. [Pg.51]

The main handicap of MD is the knowledge of the function [/( ). There are some systems where reliable approximations to the true (7( r, ) are available. This is, for example, the case of ionic oxides. (7( rJ) is in such a case made of coulombic (pairwise) interactions and short-range terms. A second example is a closed-shell molecular system. In this case the interaction potentials are separated into intraatomic and interatomic parts. A third type of physical system for which suitable approaches to [/( r, ) exist are the transition metals and their alloys. To this class of models belong the glue model and the embedded atom method. Systems where chemical bonds of molecules are broken or created are much more difficult to describe, since the only way to get a proper description of a reaction all the way between reactant and products would be to solve the quantum-mechanical problem at each step of the reaction. [Pg.663]


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See also in sourсe #XX -- [ Pg.102 ]




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