One-stage process

In the one-stage process (Fig. 2), ethylene, oxygen, and recycle gas are directed to a vertical reactor for contact with the catalyst solution under slight pressure. The water evaporated during the reaction absorbs the heat evolved, and make-up water is fed as necessary to maintain the desired catalyst concentration. The gases are water-scmbbed and the resulting acetaldehyde solution is fed to a distUlation column. The tad-gas from the scmbber is recycled to the reactor. Inert materials are eliminated from the recycle gas in a bleed-stream which flows to an auxdiary reactor for additional ethylene conversion. 

Flame or Partial Combustion Processes. In the combustion or flame processes, the necessary energy is imparted to the feedstock by the partial combustion of the hydrocarbon feed (one-stage process), or by the combustion of residual gas, or any other suitable fuel, and subsequent injection of the cracking stock into the hot combustion gases (two-stage process). A detailed discussion of the kinetics for the pyrolysis of methane for the production of acetylene by partial oxidation, and some conclusions as to reaction mechanism have been given (12). 

Electrolytic Oxidation. Electrolytic oxidation of ferromanganese or manganese metal is a one-stage process that circumvents the problem of ore impurities. Moreover, this procedure can be used with low caustic concentrations at room temperature. This process is based on the following... 

Bulk polymerisation processes have been known for many years but until the mid-1960s the only commercial process was one operated by Pechiney-St Gobain in France. This process was a one-stage process and according to one patent example vinyl chloride was polymerised with 0.8%% of its own weight of benzoyl peroxide in a rotating cylinder containing steel balls for 17 hours at 58°C. 

A one-stage process for producing vinyl acetate directly from ethylene has also been disclosed. In this process ethylene is passed through a substantially anhydrous suspension or solution of acetic acid containing cupric chloride and copper or sodium acetate together with a palladium catalyst to yield vinyl acetate. 

Fig. 119. Diagram of one- stage liquid-liquid extraction (1 - equilibrium curve, 2 - one-stage process)...

Layered-type structure, 92-100 Lewis acidity, 15 Liquid - liquid extraction collective, 276-277 counter-current scheme, 272 equipment, 273 extractants, 279-281 mechanism, 274-276 multistage counter-current, 271 multistage cross-current, 270 one-stage process, 270 principals, 267-269 process performance, 282-283 process schemes, 277,278, selective, 277-278 with 2-octanol, 284-291... 

Such a classification of technetium cluster compounds, in our opinion, reflects the relationship between the thermal stability and structure of the clusters quite well. Moreover, on the basis of this classification it is easier to follow the mechanism of the main thermochemical transitions of technetium clusters, such as (1) dehydration (2) disproportionation and related processes occurring without changes or with only small changes in mass (3) one-stage processes of thermolysis. We shall now consider these main mechanisms of the thermochemical reactions of technetium clusters in greater detail. 

From this point of view a one-stage process of simultaneous GIC exfoliation, impregnation of EG by amorphous carbon precursor and its subsequent carbonization would be very attractive. But up to now this simple one-stage process could not be realized because of high exfoliation temperature of the ordinary GICs needed (900 - 1200°C), which leads to almost complete burnout of AC precursor at the atmospheric air conditions. 

Combined with appropriate amorphous carbon precursors graphite intercalation compounds could be used in one-stage process of production of carbon-carbon composites, which could possess attractive properties for such applications as supercapacitors elements, sorbents as well as catalyst supports and materials for energy- and gas-storage systems. 

The one-stage process with THEOS proceeds differently (Figure 3.7B). The difference is in the absence of sol nanoparticles in the initial solution. There are entangled macromolecular chains (stage 1, Figure 3.7B). The silica precursor is introduced in a biopolymer solution as a monomer. The experimental results available to date (see Section 3.4.2) demonstrate that instead of sol formation there... 

It should be noted that Reaction (4) is not a one-stage process.) Both free radical N02 and highly reactive peroxynitrite are the initiators of lipid peroxidation although the elementary stages of initiation by these compounds are not fully understood. (Crow et al. [45] suggested that trans-ONOO is protonated into trans peroxynitrous acid, which is isomerized into the unstable cis form. The latter is easily decomposed to form hydroxyl radical.) Another possible mechanism of prooxidant activity of nitric oxide is the modification of unsaturated fatty acids and lipids through the formation of active nitrated lipid derivatives. 

DOC [direct oxychlorination] A one-stage process for making vinyl chloride from ethylene and chlorine. Piloted by Hoechst in Germany in 1989. 

Geigy A one-stage process for making ethylenediamine tetra-acetic acid (EDTA) from eth-ylenediamine, hydrogen cyanide, and formaldehyde. 

The process is operated in heated, batch reactors under an inert atmosphere. Two companies (Deeside Titanium, North Wales, and New Metals Industries, Nihongi, Japan) operate a one-stage process. Reactive Metals Industries Company, Ashtabula, OH, operates a two-stage process in the first stage, at 230°C, the trichloride and dichloride are formed. In the second, more sodium is added and the temperature is raised to 1,000°C. The sponge product is mixed with sodium chloride, which is leached out with dilute hydrochloric acid. Based on the work by M. A. Hunter at Rensselaer Polytechnic, New York in 1910. See also Kroll. 

After a large number of experiments, we found that the preparation could be run virtually as a one-stage process. The whole process consists simply in adding phosphorus trichloride to isopropyl alcohol, dissolved in a solvent such as carbon tetrachloride, without external cooling. The crude product (still in the solvent) is chlorinated and then heated with an inorganic fluoride, e.g. sodium fluoride. After filtration, the solvent is distilled off and the pure di-isopropyl phosphorofluoridate distilled. ... 

We have recently prepared this compound by a simple modified one-stage process (p. 58). 

Alternative One-stage Process for the Preparation of Esters of Phosphorofluoridic Acid... 

Here we will describe the one-stage process in which oxygen is used as the oxidant and all reactions take place in one vessel. 

When air is used as the oxidant, the gas cannot be recycled since inert nitrogen would accumulate in the system. The one-stage process requires recycling of the gas, because it contains unconverted ethene and thus oxygen is used. 

The technique is more efficient than the conventional Grignard reaction for three main reasons (1) it is a one-stage process (2) the yields are generally higher and (3) the final product isolation is cleaner and more convenient. 

Applying vacuum distillation in an one-stage process removes nearly 75% of the wine volatiles, predominantly owing to the transfer of esters and fusel alco-... 

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