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Water-gas mixture

When the mesophase pitch is heated, tiny spherical beads having a radial orientation of the graphite embryo form and grows in the mother pitch. When the size of the beads in the pitch reaches an appropriate size (10-30 pm), the pitch is cooled down and the beads can be collected by dissolving the pitch matrix with an appropriate solvent. The beads are then heat-treated in an oxygen/water gas mixture to produce the protective skin, as for the MCF, and then graphitized, as depicted in Figure 10. [Pg.184]

Figure 17.6 illustrates a gasification process integrated with the calcium looping process. Once the water gas mixture is formed at the exit of the gasifier, calcium oxide fines are injected into the fuel gas stream. As the fuel gas flows past the WGS catalyst, the WGS reaction takes place and forms additional C02. The injected CaO sorbent particles react with C02 and H2S in the gas stream, thereby allowing further catalytic WGS reaction to occur. The reactions involved in the calcium looping scheme are... [Pg.582]

Included in the class of fluid-entrainment pumps are not only pumps that use a fast-streaming vapor as the pump fluid, but also liquid jet pumps. The simplest and cheapest vacuum pumps are water jet pumps. As in a vapor pump (see Fig. 2.46 or 2.51), the liquid stream is first released from a nozzle and then, because of turbulence, mixes with the pumped gas in the mixing chamber. Finally, the movement of the water - gas mixture is slowed down in a Venturi tube. The ultimate total pressure in a container that is pumped by a water jet pump is determined by the vapor pressure of the water and, for example, at a water temperature of 15 °C amounts te about 17 mbar. [Pg.45]

Dalton s law states dial the total pressure P , exerted by a mixture of gases or vapors is the sum of the pressure of each gas if it were to occupy Ihe same volume by itself. The pressure of each individual gas is called its puriinl pressure. The lotal pressure of an air-water gas mixture, containing oxygen, nitrogen, and water, is equal to the sum of the partial pressures of each gas. [Pg.811]

While the effect is not shown in the Figure 5.16 isotherm, Table 5.10 shows the predicted effect of temperature on incipient hydrate structure for a excess water gas mixture of 73 mol% methane and 27 mol% ethane. As temperature increases, the incipient hydrate structure changes from sll to si to sll and back to si. [Pg.301]

Since methanol is a direct reaction product of hydrogen and carbon monoxide, it is theoretically possible by using an excess of carbon monoxide in the original water gas mixture to form first methanol and then acetic acid or ester in one operation. With this end in view, catalysts composed of metals or their compounds, i.e. of nickel, chromium, cobalt, copper, cadmium, or manganese, have been patented.1"4 Catalysts similar to those proposed for the carbon monoxide-methanol reaction and comprising the oxides of copper, tin, lead, the acetate of copper, or tire methylates of aluminum or tin, or mixtures have been claimed for the same reaction at pressures of 150 to 200 atmospheres and at about 300° C.1 4e... [Pg.93]

It is interesting to note that some of the earliest claims to processes capable of yielding oxygenated organic compounds from water gas mixtures included the formation of acids and esters. Indeed, it is probable that the subsequent success attained by the leaders in the field in directing the reactions exclusively to methanol formation served as a stimulus to those who had hopes of forming acids and esters directly. [Pg.93]

In the early experiments that were made with water-gas mixtures in attempts to synthesize valuable organic liquids, methane apparently was the only product obtained until the effect of pressure was understood, after which the progress toward methanol synthesis was rapid. Aside from the work that had to do quite largely with the production of methane for the enrichment of water-gas or other low calorific value gaseous mixtures in countries without cheap oil, considerable attention has been paid to a study of the effects of various catalysts on the synthesis from the viewpoint of perfecting the methanol and higher alcohol syntheses. Processes have, at the same time, been proposed for the synthesis of liquid fuels from water-gas mixtures in an attempt to produce motor fuels from cheap coal. [Pg.112]

Tropsch expanded the investigations of calcium oxide as a cataly for reactions in water-gas mixtures and included a study of the synthesi and decomposition of formates.118 In explaining the mechanism o methane synthesis Vignon assumed that at temperatures below the decom position of calcium carbonate (900° C.) water-gas reacts with calciur oxide to give calcium formate. [Pg.125]

The effect of pressure on the several reactions possible in the synthesis of organic liquid compounds from water-gas mixtures is shown by the change in character of the product from one predominately hydrocarbon... [Pg.127]

Fischer s work has shown that with the iron-alkali type of catalyst the character of the product may be altered by changes in the composition of the water-gas mixture. The early results have been largely confinned by subsequent workers with similar catalysts. It was found that as the ratio of carbon monoxide to hydrogen was increased the proportion of oily or water insoluble product increased at the expense of the water and water-soluble organic compounds. It has been shown that the water layer of the product may be eliminated entirely by the use of high proportions of carbon monoxide. There is a tendency, however, for the iron catalyst to promote the reaction,... [Pg.128]

Water gas (mixture of carbon monoxide and hydrogen) is prepared by passing steam over red-hot coke ... [Pg.236]

Other equilibria possible in water gas mixtures are the following ... [Pg.412]

An oil-bearing bed iikewise represents a special kind of a combustible substance. It consists of mineral ash, acting as a skeleton, and of the flammable organic part, present in the form of a strongly dispersed oil-water-gas mixture. [Pg.136]

The value of AT for the water-gas shift reaction at 500 °C is 10, In the process the amount of carbon monoxide in the final gas mixture, after removal of excess steam, had to be kept below 2% by volume. a> Calculate the ratio by volume required for the steam/water-gas mixture (at 500 °C) to achieve this. [Pg.184]

Chemical species that induce SCC in carbon and low-alloy carbon steels, even at low concentrations include hydroxides, gaseous hydrogen, gaseous chlorine, hydrogen chloride, hydrogen bromide, aqueous nitrate solutions, hydrogen sulfide gas, MnS and MnSe inclusions in the alloy. As, Sb, and Bi ions in aqueous solution, carbon monoxide-carbon dioxide-water gas mixtures. Many of these chemical systems will crack steel at room temperatures. [Pg.78]


See other pages where Water-gas mixture is mentioned: [Pg.330]    [Pg.115]    [Pg.120]    [Pg.409]    [Pg.411]    [Pg.3]    [Pg.268]    [Pg.515]   
See also in sourсe #XX -- [ Pg.730 ]




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