Paraffins, hydroxylation using

TMSP is also active for paraffin hydroxylation. Figure 63 is a summary indicating the number of turnovers of a variety of oxo transfer catalysts before catalyst decomposition (320b). When tert-butyl hydroperoxide is used as an... 

Nitrations are highly exothermic, ie, ca 126 kj/mol (30 kcal/mol). However, the heat of reaction varies with the hydrocarbon that is nitrated. The mechanism of a nitration depends on the reactants and the operating conditions. The reactions usually are either ionic or free-radical. Ionic nitrations are commonly used for aromatics many heterocycHcs hydroxyl compounds, eg, simple alcohols, glycols, glycerol, and cellulose and amines. Nitration of paraffins, cycloparaffins, and olefins frequentiy involves a free-radical reaction. Aromatic compounds and other hydrocarbons sometimes can be nitrated by free-radical reactions, but generally such reactions are less successful. 

Vapor-phase nitration of paraffin hydrocarbons, particularly propane, can be brought about by uncatalyzed contact between a large excess of hydrocarbon and nitric acid vapor at around 400°C, followed by quenching. A multiplicity of nitrated and oxidized products results from nitrating propane nitromethane, nitroethane, nitropropanes, and carbon dioxide all appear, but yields of useful products are fair. Materials of construction must be very oxidation-resistant and are usually of ceramic-lined steel. The nitroparaffins have found limited use as fuels for race cars, submarines, and model airplanes. Their reduction products, the amines, and other hydroxyl compounds resulting from aldol condensations have made a great many new aliphatic syntheses possible because of their ready reactivity. 

One particular example of what may be called a gas-liquid discharge microreactor is the work of Baba et al. (2006, 2007), who have demonstrated the generation of an atmospheric pressure glow-discharge plasma in contact with liquid paraffin, using a capacitively coupled plasma method. The choice for paraffin has two reasons no hydroxyl group present (which is thought to capture electrons, as is the case in water)... 

Zeolites are widely used as solid acid catalysts for a number of organic transformations, such as the cracking of n-paraffins which are catalysed by Bronsted acid sites. " In the case of zeolites, the so-called bridging hydroxyl groups in the i-OH-Als configuration as shown in Eq. (1) are known to act as Brdnsted acid sites and they are responsible for the ability of zeolites to catalyse the reactions. Therefore, the characterization of acidic properties of solid acids is of great importance in discussing the catalytic properties of solid acids. 

Iron-zeolite catalysts present an important type of materials with broad application for selective oxidations (i.e. benzene hydroxylation) and environmentally important processes, like SCR reduction of NOx or N2O decomposition. In the case of SCR reaction they could provide a convenient substitution of the vanadia-based system using environmentally problematic ammonia, by more convenient paraffin as a reducing agent. Unfortunately, the efficiency in utilization of paraffin is inferior in comparison to ammonia, namely due to paraffin nonselective oxidation by oxygen catalyzed by unspecified iron-oxide type species typically present in the iron-zeolite catalysts. The mostly used preparation processes include impregnation from water solutions, ion exchange procedures, both in water solution or solid state, as well as gas phase CVD. 

Naphthenic adds are a family of carboxylic acid surfactants, primarily consisting of cyclic terpenoids used in source and geochemical charaderisation of petroleum reserves (Brient, Wessner Doyle, 1995). The compwimd group is composed predominately of alkyl-substituted cycloaliphatic carboxyUc adds with smaller amounts of acyclic aliphatic (paraffinic or fatty) acids. Aromatic olefinic, hydroxyl and dibasic adds are also present as minor components of naphthenic adds. The cydoaliphatic adds include single rings and fused multiple rings. 

The presence of hydroxyl groups imparts a degree of polarity to the surface so that molecules such as water, alcohols, phenols, and amines (which can form hydrogen bonds) and unsaturated hydrocarbons (which can form ir-complexes) are adsorbed in preference to nonpolar molecules such as saturated hydrocarbons. Because of its selectivity for aromatics silica gel was used as the adsorbent in the Arosorb process for separation of aromatics from paraffins and naphthenes but by far the most important current application is as a desiccant. 

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