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Water-methane mixtures

The aim of the present work was to design and operate an apparatus in which stationary combustion and flames can be produced and sustained to pressures of 2000 bar and with environmental temperatures up to 500°C. Visual observation of the interior of the reaction vessel should be possible. Arrangements had to be made by which a gas flow of only a few microlitres per second could be fed steadily into the reaction vessel at pressures to two kilobar. A similar provision was necessary to extract small samples for product analysis at constant conditions. The principle of design and operation will be described. First results will be given for experiments with oxygen introduced into supercritical water-methane mixtures. [Pg.2]

Although the concentric nozzle (see Fig. 1 b) and the twin set of feed autoclaves permitted the simultaneous introduction of two gases into the reaction cell, during the present experiments only one gas was introduced at a time. In most cases this was oxygen into a supercritical water-methane mixture. The oxygen flow was adjusted to constant values between 1 and 6 mm s , determined from the bellows... [Pg.3]

Within the frame of the present first series of experiments it was almost always oxygen which was injected into supercritical water-methane mixtures. There were several reasons for this first choice. One of these was the desire, to study rich flames and their possible products first. Often the water to methane mole fraction ratio was 0.7 to 0.3. But mixtures down to a methane mole fraction of 0.1 were also used. It was possible, however, to inject oxygen and methane simultaneously into the supercritical water and produce a flame. Not possible was the production of true premixed flames. After a retraction of the thin inner nozzle capillary of the burner (see Fig. 1 b) the two gases could be mixed just below the reaction cell, but the flame reaction proceeded from the nozzle tip in the cell back towards this mixing point immediately. [Pg.3]

Figure 7.1-3. Steady flame when oxygen is injected into supercritical 70/30 water/methane mixture at 100 MPa and 450°C. Figure 7.1-3. Steady flame when oxygen is injected into supercritical 70/30 water/methane mixture at 100 MPa and 450°C.
Ab initio quantum mechanical methods were recently applied to the analysis of large clusters formed of one solute molecule and several molecules of solvent for water/methane mixtures. It was shown that they can provide information regarding the interaction energies and intermolecular distances between the molecules of methane and water. The obtained results were compared to the available experimental and molecular simulations regarding condensed mixtures, and agreement was found. A similar methodology of calculations will be used in the present paper as well. [Pg.341]

Because no additional parameters are needed, the model can be used for the prediction of the volumetric behavior of water + inert solvent mixtures. In Figures 2.5 and 2.6 we compare experimental and predicted molar volumes for the water + n-pentane and for the water + methane mixture, respectively. The scaling constants used for these calculations are as follows for n-pentane, T = 485 K, P = 274 MPa, p = 755 kg/m and for methane, T = 212 K, P = 252 MPa, p = 489 kg/m. As observed in the figures, in both cases there is satisfactory agreement between theory and experiment. We have applied the model to a number of mixtures with equally satisfactory results. [Pg.25]

The application system, called the biodrain, is installed within the treatment area. The biodrain aerates the soil column and any standing water. This cerates an aerobic environment in the pore spaces of the soil. Other gas mixtures can also be introduced to the soil column, such as the air/ methane mixtures used in the biodegradation of chlorinated organics. The treatment platforms can be placed in very dense configurations. International Environmental Technology claims that the cost of installation is low. [Pg.739]

Fig. 2.5.11. (a) APCI-LC-MS(+), (b) ESI-LC-MS(-t-), (c) ESI-LC-MS(+), (d) ESI-LC-MS(+), (e) APCI-LC-MS(—) and (f) ESI-LC-MS(—) reconstructed ion chromatograms (RIC) of methanolic solution of the household detergent mixture as in Fig. 2.5.2. Chromatographic conditions (a), (b), (e), and (f) RP-Cig, methanol/water gradient elution (c) ion-pairing RP-Cla using trifluoro acetic acid (TFA) (5 mmol), methanol/water gradient elution (d) isocratic elution performed on PLRP-column, eluent methanol/water methane... Fig. 2.5.11. (a) APCI-LC-MS(+), (b) ESI-LC-MS(-t-), (c) ESI-LC-MS(+), (d) ESI-LC-MS(+), (e) APCI-LC-MS(—) and (f) ESI-LC-MS(—) reconstructed ion chromatograms (RIC) of methanolic solution of the household detergent mixture as in Fig. 2.5.2. Chromatographic conditions (a), (b), (e), and (f) RP-Cig, methanol/water gradient elution (c) ion-pairing RP-Cla using trifluoro acetic acid (TFA) (5 mmol), methanol/water gradient elution (d) isocratic elution performed on PLRP-column, eluent methanol/water methane...
Carbon monoxide reacts with hydrogen gas to produce a mixture of methane, carbon dioxide, and water. (This mixture is known as substitute natural gas.)... [Pg.318]

Telluraxanthene Bis(2-bromophenyl)methane (3.33 g, 1.02 mmol) is dissolved in 300 tuL of absolute diethyl ether and, under dry nitrogen, 22 mL (36.1 mmol) of a 15% solution of n-butyllithium in hexane are added dropwise. The mixture is heated under reflux for 0.5 h, cooled to 20°C and 1.8 g (14.1 mmol) of finely powdered tellurium are added. The resultant mixture is heated under reflux for 2 h and then poured into ice/water. The mixture is extracted with chloroform, the extract is filtered and the solvent is evaporated in a rotatory evaporator at 20°C under aspirator vacuum. The residue is recrystallized from diethyl ether/petroleum ether after addition of activated charcoal. Yield 1.42 g (47%) m.p. 151°C. [Pg.313]

The reactor start-up was performed by feeding a water-free mixture of methane and air with an O2/CH4 molar ratio of 1.36 and by inducing for few seconds the voltaic arc between the spark plugs. When the mixture is ignited, the temperature on the SiC foam suddenly (1 min) reaches around 1000 °C. Furthermore, due to the heat transfer, the temperature in the catalytic zone reaches in about 2 min the light-off value with full reactants conversion. The whole start-up phase is no longer than 3 min. [Pg.307]

The electron capture detector (ECD) is also a concentration-dependent detector, and like the TCD will give a higher response for a given compound at lower carrier flowrates. Carrier flow-rate must be carefully controlled. Usually a 95% argon - 5% methane mixture is used for carrier gas. Presence of oxygen or water in the carrier gas results in loss of sensitivity and a compression of the linear range. [Pg.338]

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]

Stewart and Hack (5.) have presented operating characteristics of pressure swing adsorption systems for reducing impurities in a hydrogen stream from 40 vol percent to 1 ppm. Impurities included ammonia, water, methane, carbon monoxide, carbon dioxide, nitrogen, and several hydrocarbons. In this study heatless adsorption is used to separate hydrogen sulfide-hydrogen mixtures and the experimental results are compared with theoretical models. [Pg.261]

The experiment began by charging the equilibrium cell with about 30 cm3 of either phenoPp-cresol or phenol-water solution mixture. The cell was then pressurized with either methane or carbon dioxide until the phenol clathrate formed under sufficient pressure. The systems were cooled to about 5 K below the anticipated clathrate-forming temperature. Clathrate nucleation was then induced by agitating the magnetic spin bar. After the clathrates formed, the cell temperature was slowly increased until the clathrate phase coexisted with the liquid and vapor phases. The nucleation and dissociation steps were repeated at least twice in order to diminish hysteresis phenomenon. The clathrates, however, exhibited minimal hysteresis and the excellent reproducibility of dissociation pressures was attained for all the temperatures and found to be within 0.1 K and 1.0 bar at each time. When a minute amount of phenol or p-cresol clathrate crystals remains and the system temperature was kept constant for at least 8 hours after attaining pressure stabilization, the pressure was considered as an equilibrium dissociation pressure at that specified temperature. [Pg.437]

Song, K.Y. and R. Kobayashi. 1989. Water content values of a C02 - 5.31 mol percent methane mixture. Research Report RR-120, Gas Processors Association, Tulsa, OK. [Pg.125]

Given in the literature are vapor pressure data for acetaldehyde and its aqueous solutions (1—3) vapor—liquid equilibria data for acetaldehyde—ethylene oxide [75-21-8] (1), acetaldehyde—methanol [67-56-1] (4), sulfur dioxide [7446-09-5]— acetaldehyde—water (5), acetaldehyde—water—methanol (6) the azeotropes of acetaldehyde—butane [106-97-8] and acetaldehyde—ethyl ether (7) solubility data for acetaldehyde—water—methane [74-82-8] (8), acetaldehyde—methane (9) densities and refractive indexes of acetaldehyde for temperatures 0—20°C (2) compressibility and viscosity at high pressure (10) thermodynamic data (11—13) pressure—enthalpy diagram for acetaldehyde (14) specific gravities of acetaldehyde—paraldehyde and acetaldehyde—acetaldol mixtures at 20/20°C vs composition (7) boiling point vs composition of acetaldehyde—water at 101.3 kPa (1 atm) and integral heat of solution of acetaldehyde in water at 11°C (7). [Pg.49]

Sample Pretreatment. Aminonitrazepam was extracted from the postmortem blood by means of a solid-phase isolation on an Extrelut cartridge column (Merck, Darmstadt, FRG). The cartridge was pretreated before use. It was washed with a 1 1 methanol dichloro-methane mixture, dried and treated with ammonia vapor. The postmortem blood sample (1 ml) was diluted with 0.5 ml water and sucked through the cartridge. The column was eluted with 8 ml of diethyl ether. The eluate was evaporated to dryness and redissolved in methanol. [Pg.180]

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]


See other pages where Water-methane mixtures is mentioned: [Pg.3]    [Pg.4]    [Pg.4]    [Pg.4]    [Pg.4]    [Pg.409]    [Pg.317]    [Pg.248]    [Pg.618]    [Pg.3]    [Pg.4]    [Pg.4]    [Pg.4]    [Pg.4]    [Pg.409]    [Pg.317]    [Pg.248]    [Pg.618]    [Pg.49]    [Pg.64]    [Pg.514]    [Pg.37]    [Pg.119]    [Pg.3]    [Pg.64]    [Pg.478]    [Pg.546]    [Pg.106]    [Pg.310]    [Pg.199]    [Pg.191]    [Pg.94]    [Pg.331]    [Pg.335]    [Pg.338]    [Pg.43]    [Pg.227]   
See also in sourсe #XX -- [ Pg.314 ]




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