Carbon dioxide—oxygen exchange reactions

Fuel cell applications Manganese dioxide as a new cathode catalyst in microbial fuel cells [118] OMS-2 catalysts in proton exchange membrane fuel cell applications [119] An improved cathode for alkaline fuel cells [120] Nanostructured manganese oxide as a cathodic catalyst for enhanced oxygen reduction in a microbial fuel cell [121] Carbon-supported tetragonal MnOOH catalysts for oxygen reduction reaction in alkaline media [122]... 

It is clear that not all possible contaminants can be tested, but sources of contamination must be considered and tests run on the reaction in the presence of the most likely occurring ones. An approach to evaluating the problem of contamination is in the setting-up of a plant material matrix [1]. An example of potential contaminants to be considered, and sometimes overlooked, includes the heat transfer fluids to evaluate the consequences of heat exchanger, coil, or jacket failures. Contaminants which are introduced by other sources, for example, air (oxygen), carbon dioxide, water, metals, lubricants, and greases must also be considered. Also, the effects of chemicals which are used elsewhere in the plant and which could be introduced by mistake should be evaluated and perhaps tested. The possible contaminants in the reactor feeds must also be considered. 

Lithiation of dibenzofuran with butyllithium and mercuration both occur at the 4-position. Thallation occurs at the 2-position, however (57IZV1391). The mercury and thallium derivatives serve as a source of the iodo compounds by reaction with iodine. Bromodibenzofurans undergo bromine/lithium exchange with butyllithium and the derived lithio compounds may be converted into phenols by reaction with molecular oxygen in the presence of a Grignard reagent, into amines by reaction with O-methylhydroxylamine, into sulfinic acids by reaction with sulfur dioxide, into carboxylic acids by reaction with carbon dioxide and into methyl derivatives by reaction with methyl sulfate (Scheme 100). This last reaction... 

An investigation of the reaction of group 6 metal carbonyls with OH- in the absence of a Lewis base ligand indicates that oxygen exchange is a much more facile process than elimination of carbon dioxide from 53 (67). 

In the absence of oxygen and the possible exchange of ammonia on clays, the only reaction affecting sulfate, carbon dioxide and ammonia is that of sulfate reduction vdiereby sulfate is consumed as a reactant and carbon dioxide and ammonia are liberated from the decomposing organic matter. Thus the expressions for CR for these substances will be the first order reaction term K (OC) modified by the appropriate stoichiometric coefficients. These coefficients are determined by the reaction chosen to describe the process of sulfate reduction. A reaction that has been used successfully by Berner (2 and others (2) is... 

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