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Hydrocarbon oxidation paraffin

Oxidized paraffin soaps comprise saturated fatly acid, oxyacid (such as alcohol acid and ketonic acid), dicarboxylic acid, unsaponitied oxides, and unoxidized hydrocarbons. Oxidized paraffin soaps that are used as collector are comprised of fatty acids because mostly unsaponified oxides and unoxidized hydrocarbons had been removed from the product. The proportion of saturated fatty acid in oxidized paraffin soaps is about 80 %. And the proportion of oxyacid is about 5-10 %. The proportion of unsaponified oxides is about 2-3 %. [Pg.73]

It is not feasible to model the reaction of each hydrocarbon species with oxides of nitrogen. Therefore, hydrocarbon species with similar reactivities are lumped together, e.g., into four groups of reactive hydrocarbons olefins, paraffins, aldehydes, and aromatics (32). [Pg.330]

A very serious problem was to clear up the formation of hydroperoxides as the primary product of the oxidation of a linear aliphatic hydrocarbon. Paraffins can be oxidized by dioxygen at an elevated temperature (more than 400 K). In addition, the formed secondary hydroperoxides are easily decomposed. As a result, the products of hydroperoxide decomposition are formed at low conversion of hydrocarbon. The question of the role of hydroperoxide among the products of hydrocarbon oxidation has been specially studied on the basis of decane oxidation [82]. The kinetics of the formation of hydroperoxide and other products of oxidation in oxidized decane at 413 K was studied. In addition, the kinetics of hydroperoxide decomposition in the oxidized decane was also studied. The comparison of the rates of hydroperoxide decomposition and formation other products (alcohol, ketones, and acids) proved that practically all these products were formed due to hydroperoxide decomposition. Small amounts of alcohols and ketones were found to be formed in parallel with ROOH. Their formation was explained on the basis of the disproportionation of peroxide radicals in parallel with the reaction R02 + RH. [Pg.40]

The initiating action of ozone on hydrocarbon oxidation was demonstrated in the case of oxidation of paraffin wax [110] and isodecane [111]. The results of these experiments were described in a monograph [109]. The detailed kinetic study of cyclohexane and cumene oxidation by a mixture of dioxygen and ozone was performed by Komissarov [112]. Ozone is known to be a very active oxidizing agent [113 116]. Ozone reacts with C—H bonds of hydrocarbons and other organic compounds with free radical formation, which was proved by different experimental methods. [Pg.130]

Scheme A. This scheme is typical of the hydrocarbons, which are oxidized with the production of secondary hydroperoxides (nonbranched paraffins, cycloparaffins, alkylaro-matic hydrocarbons of the PhCH2R type) [3,146]. Hydroperoxide initiates free radicals by the reaction with RH and is decomposed by reactions with peroxyl and alkoxyl radicals. The rate of initiation by the reaction of hydrocarbon with dioxygen is negligible. Chains are terminated by the reaction of two peroxyl radicals. The rates of chain initiation by the reactions of hydroperoxide with other products are very low (for simplicity). The rate of hydroperoxide accumulation during hydrocarbon oxidation should be equal to ... Scheme A. This scheme is typical of the hydrocarbons, which are oxidized with the production of secondary hydroperoxides (nonbranched paraffins, cycloparaffins, alkylaro-matic hydrocarbons of the PhCH2R type) [3,146]. Hydroperoxide initiates free radicals by the reaction with RH and is decomposed by reactions with peroxyl and alkoxyl radicals. The rate of initiation by the reaction of hydrocarbon with dioxygen is negligible. Chains are terminated by the reaction of two peroxyl radicals. The rates of chain initiation by the reactions of hydroperoxide with other products are very low (for simplicity). The rate of hydroperoxide accumulation during hydrocarbon oxidation should be equal to ...
When variable-valence metals are used as catalysts in the oxidation of hydrocarbons, the chain termination via such reactions manifests itself later in the process. This case has specially been studied in relation to the oxidation of paraffins to fatty acids in the presence of the K Mn catalyst [57], which ensures a high oxidation rate and a high selectivity of formation of the target product (carboxylic acids). As the reaction occurs, alcohols are accumulated in the reaction mixture, and their oxidation is accompanied by the formation of hydroxyperoxyl radicals. The more extensively the oxidation occurs, the higher the concentration of alcohols in the oxidized paraffin, and, hence, the higher is the kinetic... [Pg.589]

C=C bond hydrogenation, olefin + H2-> paraffin C=0 bond hydrogenation, acetone + H2 -> isopropanol Complete oxidation of hydrocarbons, oxidation of CO 3H2 + N2 -> 2NH3... [Pg.357]

Aliphatic hydrocarbons petrol, paraffin. In the U.S.A. several types of combustibles for liquid propellant jet aircraft are used. One of them, i.e. JP-4, is employed for rocket propulsion, with nitric acid as an oxidizing agent (it can also be used with hydrogen peroxide or liquid oxygen). The specification of JP-4, is as follows ... [Pg.293]

The statements of the possible role of HO radicals in saturated hydrocarbon oxidation processes is proved by experimentally determined formation of sufficient amounts of hydrogen peroxide and HO radicals during oxidation of propane [27] and paraffin dehydrogenation products [28-30],... [Pg.15]

In its literal form, this reaction is only of academic interest because a molecule is unlikely to break up or isomerize irreversibly in two or more different ways. However, situations frequently encountered in practice are those of multistep parallel first-order decomposition reactions and of parallel reactions that involve coreactants but are pseudo-first order in the reactant A. An example of the first kind is dehydrogenation of paraffins, examples of the second kind include hydration, hydrochlorination, hydroformylation, and hydrocyanation of olefins and some hydrocarbon oxidation reactions. All these reactions are multistep, but the great majority are first order in the respective hydrocarbon, and pseudo-first order if any co-reactant concentration is kept constant. [Pg.87]

Further evidence in support of the peroxide theory has resulted from a study of the slow oxidation of pentene/5 This work is of more particular interest from the point of view of paraffin hydrocarbon oxidation as applied to knocking phenomena, however, and will not be discussed here. [Pg.211]

For the oxidation of CO, methane and olefins, Pd is a better catalyst than Pt. For the oxidation of paraffins higher than propane, Pt is better than Pd. Under conditions of hydrocarbon oxidation, the metal surface is fully covered with oxygen. Hence there is no influence of oxygen pressure on the reaction rate (sometimes there is even a slight negative influence on the rate). [Pg.102]

However, there are one or two instances where enough is known about catalysts of these types to justify some attention at this point. Some of the most thoroughly investigated cases constitute the group of catalysts used in the ring-closing reactions which lead to the production of aromatic hydrocarbons from paraffins or olefins. These consist of oxides of vanadium, chromium, and molybdenum, or of complex and supported catalysts containing one of these oxides. [Pg.101]

On the one hand, hydrocarbon oxidation is a model reaction which enables special features of these catalytic processes to be analyzed. In addition, this resembles, to a considerable extent, enzymatic catalysis it also proceeds at low temperatures with high selectivity and requires small quantities of catalyst [128]. There have been no systematic investigations of catalytic liquid-phase oxidation of paraffins by macromolecular complexes and the scarce data are presented mainly in patents. (Pd complexes bound to ion-exchange resins are highly active in hydrogen oxidation by air (see, for instance [129])). [Pg.545]

Hydrocarbon chain length of oxidized paraffin soaps... [Pg.73]

According to the reports, hydrocarbon chain lengths of fatty acids in oxidized paraffin soaps are given as follows [4] ... [Pg.73]

Hydrocarbon chain lengths of saturated fatty acids in oxidized paraffin soaps prepared in a certain Chinese factory are given by the following ... [Pg.73]

Most FR additives contain bromine, chlorine, phosphorus, antimony, or aluminium. Among the main types are brominated hydrocarbons additive and reactive phosphate esters non-halogenated and halogenated antimony oxide trioxide and pentoxide, and sodium derivatives chlorinated hydrocarbons chlorinated paraffins, chlorinated cycloaliphatics. Other types include chlorinated/ brominated compounds, fluorinated compounds, magnesium carbonate, magnesium hydroxide, melamine, molybdenum compounds, silicone polymer. [Pg.117]

The original method for the manufacture of ethyne, the action of water on calcium carbide, is still of very great importance, but newer methods include the pyrolysis of the lower paraffins in the presence of steam, the partial oxidation of natural gas (methane) and the cracking of hydrocarbons in an electric arc. [Pg.169]

Secondary alcohols (C q—for surfactant iatermediates are produced by hydrolysis of secondary alkyl borate or boroxiae esters formed when paraffin hydrocarbons are air-oxidized ia the presence of boric acid [10043-35-3] (19,20). Union Carbide Corporation operated a plant ia the United States from 1964 until 1977. A plant built by Nippon Shokubai (Japan Catalytic Chemical) ia 1972 ia Kawasaki, Japan was expanded to 30,000 t/yr capacity ia 1980 (20). The process has been operated iadustriaHy ia the USSR siace 1959 (21). Also, predominantiy primary alcohols are produced ia large volumes ia the USSR by reduction of fatty acids, or their methyl esters, from permanganate-catalyzed air oxidation of paraffin hydrocarbons (22). The paraffin oxidation is carried out ia the temperature range 150—180°C at a paraffin conversion generally below 20% to a mixture of trialkyl borate, (RO)2B, and trialkyl boroxiae, (ROBO). Unconverted paraffin is separated from the product mixture by flash distillation. After hydrolysis of residual borate esters, the boric acid is recovered for recycle and the alcohols are purified by washing and distillation (19,20). [Pg.460]


See other pages where Hydrocarbon oxidation paraffin is mentioned: [Pg.296]    [Pg.254]    [Pg.84]    [Pg.113]    [Pg.399]    [Pg.73]    [Pg.104]    [Pg.453]    [Pg.245]    [Pg.306]    [Pg.18]    [Pg.182]    [Pg.19]    [Pg.1443]    [Pg.427]    [Pg.74]    [Pg.204]    [Pg.459]    [Pg.467]    [Pg.18]    [Pg.258]   
See also in sourсe #XX -- [ Pg.120 ]

See also in sourсe #XX -- [ Pg.97 ]




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