Oxygenated mixture from pressure oxidation

This oxide has not yet been prepared as a pure material but was observed only in dilute solution. If liquid sulfur is burned in pure oxygen under reduced pressure a mixture of S2O, SO2, and little SO3 is formed (see above). The latter can be removed by passing the gas through a filter of glass-wool. Bubbling of the S2O-SO2 mixture into trichloromethane at -60 °G results in a yellow solution which can be freed from most of the dissolved SO2 in a vacuum. The analytical and spectroscopic data then indicate the presence of S5O (up to 77 mmol G ) and of traces of SO2 in the solution [13] ... 

The oxide is stable above 575°C. Thus, it can be prepared by heating iron with oxygen under appropriate pressure at 575°C. Also, iron(ll) oxide has been prepared by saturating the fused triiron tetroxide with iron, powdering the mixture, followed by magnetic separation of the oxide from excess iron (Sidgwick, N.V. 1950. The Chemical Elements and Their Compounds, Vol.2, pp 1328, Oxford Clarendon Press). 

Oxidation Unit The oxidation unit is an empty pressure vessel that takes input reaction gases and blends in additional air from the bleaching column. The extra oxygen provided enables further oxidation to occur and raises the gas mixture temperature to 140°C. At the top of the oxidation unit is a mist eliminator to prevent carry over of acid vapour by entrainment. At the bottom of the vessel is the weak-acid drain. The oxidation unit is constructed from SS304L and has a design pressure of 1200 kPa... 

The products of oxidation have been investigated.4 When the oxidation was carried out in moist air or oxygen the partial pressures of which were varied between 100 and 1200 mm. the product was a nearly constant mixture of the tetroxide and pentoxide. The empirical composition PO2.10 is nearly the same as that of the corresponding product derived from P406. It is considered that the phosphorus trioxide is formed as an intermediate stage which does not accumulate in the system. 

The fact that ethane has been found to be so much more readily reacted upon by oxygen than methane to yield larger quantities of formaldehyde than is obtainable from methane, makes it seem that some of the high yields reported from methane may have in most part beeu due to ethane admixed in the hydrocarbon gas used, rather than the attainment of unusually productive operating conditions. This is true of data from experiments in which natural gas had been used for oxidation. The pressure oxidation process producing a mixture of methanol, formaldehyde, and acetaldehyde from natural gas utilizes the hydrocarbons higher than methane, and especially ethane. ... 

In general, the oxidized product from the pressure oxidation of hydrocarbons from ethane up to butane or higher in molecular weight may be expected to consist of a mixture of oxygenated organic compounds comprising alcohols, aldehydes, ketones, acids, esters, etc., together with water... 

Results from the oxidation of propane with elemental oxygen at pressures of about 2000 pounds per square inch (136 atmospheres) and at temperatures of about 300° to 350° C. show that more than 40 per cent of the oxygen may appear in the form of liquid organic oxidation products.10Bf However, it must be remembered that oxygen concentrations of the order of only 5 to IS mol per cent are used in the feed mixture and that, consequently, the per pass conversion of hydrocarbon to oxygenated product is not very high. A typical product from the oxidation of propane at 136 atmospheres pressure under such conditions consists of ... 

Vapor-phase reaction between ozone and olefins is quite rapid, the overall reactions become complicated, and stoichiometry varies with the reaction pressures. A 3 mole per cent mixture of OTOne in oxygen reacts with methane, propane, i -butane, and isobutane at 25-50 C. The reaction of ozone with isobutane resulted in formation of ferf-butanol plus one-third to one-half as much acetone, the combined yield being about equivalent to ozone reacted. Acetone was formed from propane oxidation. 

One object of this investigation was to determine the equilibrium composition of sodium superoxide-sodium peroxide mixtures with oxygen at various pressures and temperatures. A group of experiments was performed in which the temperature was varied from 450 to 550 0. and the oxygen pressure from 102 to 137 atm. Both cadmium oxide and titanium oxide catalysts were used. The product composition, expressed in oxygen content, for various exposures at these conditions, is tabulated in Table I. 

Extensive research on hydrogen sulfide removal from natural gas was carried out by Tollefson and coworkers [65, 67—72]. The oxidation of hydrogen sulfide was studied in both fluidized and fixed bed reactors at a wide temperature range (398-473 K) and a pressure range between 230-320 kPa with H2S concentration between 0.(K)3 to 6 % and oxygen content from one to four times the stoichiometric ratio with respect to hydrogen sulfide concentration present in the mixture. The typical experimental set up for fixed bed reactor is presented in Fig.25. 

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